Ford F150 3.73 vs 3.31 Gears (5L Coyote V8) | Does It ACTUALLY HURT FUEL ECONOMY ??
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- čas přidán 27. 06. 2024
- I review the 2024 Ford f150 with the 5L coyote V8 engine and compare 3.73 gears to the standard 3.31 gears when it comes to Fuel Economy performance. I compare fuel economy (MPG) and to my surprise it seems like the 3.73 gears were more fuel efficient which to me signifies that gearing does not make that much of an impact on unloaded ford f150 trucks.
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I was very excited to test out if Gearing in a truck really makes a real world difference in fuel economy. Both these 2024 Ford F150 trucks have the 5L coyote V8 in them with the 10 speed transmission. 4x4 trucks with crew cab so they are basically identical trucks. the only difference is the gearing.
I take these trucks on my 85 fuel economy loop to determine if gearing does indeed affect the fuel economy.
in theory the 3.31 gears should result in better fuel economy whereas the 3.73 gears do give better acceleration but this results in the engine rotating faster thus drinking more fuel.
00:00 - Intro
00:31 - F150 Specs
02:34 - City Fuel Economy (35 MPH)
03:58 - Country Fuel Economy (56 MPH)
05:06 - 3.73 Gearing Explained
06:15 - Highway Fuel Economy (70 MPH)
08:05 - Real RESULTS - Auta a dopravní prostředky
Swapping the wheels/ tires for consistency was brilliant
Gotta luv that. The 5.0 with 3.73 gear ratio is the configuration I'd go with
After this comparison. 3.73 is the only way to order a 5L
That's what I have and it's great for sure!
Works well with my 5.4 and has convinced me that is the only ratio I will ever have.
You need to teach the TFL Truck and other auto journalists how you find trucks with gearing to compare. Love those guys but laugh when they compare a 3.73 truck with a 3.23 truck etc. And say oh it shouldn't matter. It does.
It’s certainly tough but you would think a massive channel like TFL could ask for the same gearing. But I think like the average viewer wouldn’t think twice about it unfortunately
@TheGettyAdventures yes sir. I have always been a fan of high aspect ratio gearing as nothing compares to the mechanical advantage. When I came back from the Gulf War my beloved 300 six died but it had the crazy 2.73 gears and five speed overdrive in that 83 truck. Horrible for loads. Next truck was a 1990 used chevy Z 71 with 3.73s and the indestructible 350 with throttle body fuel injection...and an unbelievable 17 to 18 mpgs highway. 400k miles later i had a straight 6 in the 96 jeep grand Cherokee with 3.73s and 350k miles later I still have a Ford Ranger 4.0 4 wheel drive with 4.10s and running like new. Gearing and changing fluid and not over pulling ensures all my vehicles run long long times and they get better mpgs under load. My 22 Powerboost is a great truck but I would trade it in a heart beat for a 21 or 22 F 150 with the hard to find Heavy Duty Payload Package and 3.73 gears and over 2500 pounds Payload. Thanks for listening
@@slmjake I have a new Silverado 3.0 Duramax with 3.73's and the 10-speed. I love climbing fairly steep grades in 10th gear with just a hint of cummins-like diesel burble. When I found one with 3.73's I scooped it up immediately. The taller gears probably do better if you live in extremely flat terrain, but here in the hills the axle ratio makes a difference.
3.73 vs 3.31 is pretty darn close to 3.73 vs 3.23😂🤣
Agree, TFL is sloppy with details but they are not alone in that. It's more of a talking heads with trucks channel. BUT, I do like the IKE tests but even that's gimmicky.
I've Got a 2019 F-150 STX 4X4 Crew Cab, 2.7L EcoBoost 10 Speed Automatic, 3.55 Gears. I Run 75 MPH and Get 22 to 23 on the Interstate and 19 to 20 In Town going 5 Mph Over Speed Limit. I Love My Truck.
the 2.7 Ecoboost is a solid engine. I really liked my time with it
Great comparison! This channel is killer.
The 3:73 lets the tranny shift up sooner to the 10th speed.
I bought a 2nd hand ford , it was in the way it was equipped what I was looking for, but for one thing it had the 3:73 gears, I bought it any way, wasn`t going to be a deal breaker for 1-2 miles to the gallon.
To my surprise it gave great fuel consumption numbers.
This is my supposition as well. The ratio spread in a modern AT is nuts. Also the speeds of our Canadian cousin here are a bit more….sedate….than what we drive in Texas
One thought maybe, were the tires you took off larger diameter? If that was the case the speedo would be off, resulting in the trip meter thinking it travelled more than it actually did, resulting in higher mpg numbers.
Hi, I have the 3.73 gears and I have seen exactly what you just reported. I saw the 3.31 gear video you made and wondered if you would test the other truck. I do not think it is a fluke, as my friend has a 3.31 version of the truck, and from his comments, my mpg is equal to or better than his. I have driven both and my truck has noticeably better power, just as you stated. I think this comes down to the 10 speed tranny being able to optimize the engine load. With the 3.73s, the sweet spot of the 5.0 engine is used for more time than with the 3.31s....maybe? Keep up the excellent work.
Same here. Maybe they have slightly different programming?
@@kylesummers1565 Dude, could be, I am not well versed with how the engineers did all of that. pm
3:31 is a higher gear ratio than 3:73, which means 3:31 gets better fuel mileage while 3:73's will give you better pulling power
Sometimes a lower rear axle (numerically high) can get better mpgs but only towing and slower speed highway.
@@shelhawke7206That's generally how it works, but the 10 speed is a difference maker.
I was gonna comment about the tires. I'm glad you swapped them.
Another great side by side. I absolutely love these
Love this video! Your channel and TFL are the 2 truck channels I watch! I’d almost argue your videos are more scientific
This will be interesting to watch
Thanks man!
I believe some of the other comments may have found the issue. If there is any difference in the tire diameter, the computer system may not be capturing any of the data correctly for this comparison. This can potentially cause differences in the speedometer, odometer, etc, along with the computer calculations using that data, most importantly MPG for this test. Regardless, another great video and the entire series is helpful to me in making decisions for future purchases. Thanks!!!
I can’t say anything about the Coyote, but my 2017 2.7 Ecoboost with 3:55 and a 6 speed got about 1.5 mpg around town less than my 2023 2.7 Ecoboost with 3:73 and 10 speed, I also think Ford softened the throttle response and my 17 didn’t have a economy mode. From Princeton WV to Lewisburg WV and back all 2 lane rural roads about 70 miles each way I got indicated 25.8 and calculated I got 25.5, driving like a Grandpaw, cause I am. I had a 2002 Tacoma 2.7 4wd that got 21.5 on around town or on the highway, such a good lil truck till rust got the frame.
There IS a difference in the drivetrain! The 3.31 ratio is in an 8.8. inch rear axle, as the 3.73 sits within an 9.75 inch rear axle that is considered a 3/4 float rearend, as opposed to a semi-float 8.8 axle. The wheel hubs are different on the 9.75 inch axle. Great videos!!!
I think the better milage with the 373's is all about how much load the engine is under to propel the truck down the road. 373's must be the sweet spot for the F150's. You will notice that the F150 powerboost is only available with the 373 gear set. I'm sure Ford did that on purpose! I actually have the 373's in my 2017 Ram 2500 CTD and get 20+ mpg on the highway consistently. I'm a big fan of 373's.
Removing the wheels got you a sub.
Keep up the good work
Could it have to do with the 3.73 gears sitting in a better area on the torque curve meaning it’s more efficient? Maybe the 3.31 are slightly running below the optimal RPM range for the engine? Idk just a thought
Great comparison
Ram did extensive tests with gear ratios a few years ago. Ram ratios are 3.55 & 3.92. In the test it was one mpg difference, big deal. I ordered my last 6 Ram trucks with 3.92 every time. Better power off the line, higher tow rating, and as for mpg, I just went on a 375 miles trip and set cruise at 72 mph, both ways I got 20 mpg. My truck isn’t light either, 6400 lb, crew cab, 6.5 ft bed, and the Hemi, not complaining!! Now I also realize that if I went faster it could drop a bit, or slower could get better mpg, but again not complaining! Now, I don’t know how Ram tested, but with the benefits I listed, I think in the real world the 3.92 could get a speck better if side by side testing was done because the motor isn’t lugging as much on the highway with the 3.92 gears. With my 3.92, 8 speed transmission at 72 mph the tach was about 2050-2100 rpm. So with 3.55’s it would of course be lugging more and I think possible lower mpg.
My 3.21 Ram would like a word 😂
Wow .thanks for all your efforts. Good video very informative. 👍🇺🇲
I have an 18 302A crewcab FX4 with a GEN3 5L/10R80 and 3.73's, and my wife has a 17 501A crewcab 4X4 with a GEN2 3.5L/10R80 and 3.31's. When I'm on petrol and not E85, my wifes 3.5L/3.31 truck gets about 2 - 2.5 better MPG's than my 5L/3.73 truck. Both on a 275/55-20. In fact my truck still has an OEM style GY Wrangler with the RWL, (same tire it came factory with) where my wifes truck is running a noticeably more aggressive tread with a GY Wrangler Ultra Terrain. My wifes 3.5L truck is stock, where my 5L truck has an AMRL tune on it.
Love this video. Is the 2024 Coyote still a 3rd gen, or have the quietly slotted in a 4th gen ?
Great video. I would like to see the test with a 4.10 axle ratio. The ten-speed transmission allows a lot more latitude.
it would be cool if ford offered the 4.10 gear ratio on the 5L and the normal 3.5L ecoboost.
@@TheGettyAdventures I believe they do special order but that is rarely done anymore.
@harveypaxton1232 it wasnt available when i ordered my 23 f150. I went with 3.73
@@ShopJock Good to know. I probably won’t be buying a new Ford soon. I’m surprised all these trucks with 22’s and 24’ will even run.
It's Raptor only now.
With the 3:73 gears the engine is not working as hard with these gears ⚙️
We 373 on our 2017 5 litre 6 speed. We love it. Has good get up and go. Reva a little higher on the highway though.
Great video and glad you made this one with the 3:73 gears. I think the truck doesn't have to work as hard to get up to the desired speed because as mentioned in another post the trans is doing the most work to optimize load carrying and consumption of fuel. Quicker to your speed but less load on the engine means less fuel demand>>>>My guess. How about trying an F150 with 4:10 gearing if they make such a beast. Thanks for your video I really enjoy watching them. Cheers!!
It's all about the final ratio vs the torque needed for the drive.
If the torque requirement exceeds 75% of max at the cruising RPMs, the engine, if gasoline, goes into the enrichment scenario, to prevent detonation, ladies and gentlemen. 100% torque requires 60-to 70% more fuel for 33% more power! With diesel, peak efficiency (BSFC) occurs at 85-90% of peak load and 100% load only reduces efficiency by 1%. Also, diesels are much, much more efficient at low loads than gassers, so tall gearing and massive torque engines / with aero aids yield big savings
In my day late 1970s, diesel rigs had no aero improvements for some companies, and Cummins engines were running 64 mph with 4.33 gears and getting 4.2 mpg. I even got as low as 3.2 running a big CAT with monster torque and no aero aids at 70mph into a strong headwind! Recently I talked to a Volvo truck semi owner operator which was was cruised always at 63mph, with 1,950 lbs/ ft torque at only
1,175 RPMs, some 1000 RPMs less, with full aero aids on tractor and trailer and super single tires. He gets 8.1 MPG hauling 15% more freight per load! the difference? 45 years of technology!
Yesss Alex you nailed it!!!! Excellent comparison. I don't think you missed a thing. I believe it does better because the engine isn't working as hard so it doesn't matter as much that it's turning more RPM. That's just my thinking behind it unless the 3.73 truck weighs less with the new front end. Maybe when you were towing with it on the highway the wind picked up so that's why the fuel economy was less, or a next step further maybe the tow haul programming isn't quite right😊
I went with the 3.73 on my 2024 F250 with a 7.3 liter gas engine. I tow periodically and do highway speeds most of the rest of the time. I’ve been happy with the mileage so far… 17.5 miles per gallon. Not as good as my previous diesel, but this engine is not going to have all the after treatment problems at 160,000 miles like the diesel. When you think about it, 17.5 miles per gallon is amazing for such a large truck and huge gas engine. I did wonder if the 3.73 gears would hurt the mileage. Great video.
Can't go wrong with the 7.3L engine. Not as powerful as the diesel but going to be a great workhorse without all the emission issues.
On a 250, the 3.73 is a must if you tow big regularly. If people aren't happy with their mpgs, they can always drive slower. I always laugh when I see a 3/4 and up truck towing a 16ft fishing boat that my crossover could pull easily and is much lighter than what I have towed.
Here are some differences: 2024 5.0 gets a GPF in the exhaust and therefore Ford removed the flex fuel compatibility. 2023 5.0 does not have a GPF and can run E85. Since Ford removed FFV in 2024 it’s possible the engine tuning was modified to better align with its exhaust restriction resulting in a change in fuel economy. If you ran the test again would be good to use the same model year and also tell us what fuel octane you are running. Love your videos!
I hope you're either F'in joking, or wrong. My 18 5L loves the E85, and gets it exclusively. Why does a 5L need a GPF? Why would some overboosted 6 cylinder produce any less carbon emissions? The automakers both foreign and domestic need to band together, and start refusing to abide by the EPA's unrealistic expectations. They'll chill out when they start thinking back to 08/09 and remember the importance of the automakers proven by the crazy bailout that the government handed out. The automakers need to give the EPA the middle finger, and tell the EPA that they'll start doing this BS when they get countries like India and China that both produce way more pollution than us to get on board with this emissions BS.
The EPA thinks that they're Captain Planet and are going to save the Earth. Actually that's incorrect. They know they're on some BS, and are collecting taxpayers money to do nothing worthwhile, but they try and make it seem like they're doing something important.
@@JROC734 It's unfortunate. Ford has been slowly rolling out GPF's in all their ICE vehicles. It started with Euro regulations requiring GPF's for many years and those parts are now spreading to our market.
@@GotThrottles What is GBF?
@@Moondoggy1941 gasoline particulate filter. Similar to a DPF on a diesel, it has added sensors and regen to clean it out.
I would imagine it’s spending more time in cylinder deactivation with the 3.73 gearing. My 3.31 is always lugging in top gear and cylinder deactivation never stays on for long. I also find that driving in sport mode doesn’t really make my MPG go down at all (unless I’m being leadfooted)
Curious though on traffic in town- how many accelerations/stops? On such a short term test the stops and starts make a huge difference.
Were you clearing the computer for each section of test or was it running total? Just curious...
Overall good test. Seems odd tho that running at higher rpms yielded better mpg. Were they same trim and weight?
Good video tho, will watch others from you. Cheers!
I have a 13 f150 5.0 with the 6speed. I've found that if I lock out 6 while pulling a trailer on the highway the fuel economy improves just a hair, I always attributed it to the fact that the little bump in rpms put the provided the extra torque needed to keep it from lugging.
This video is the best example of apple to apple comparisen to define gear ration
It makes sense. It likely works the same on turbos with electronic wastegates. The Gen 3.5 coyotes have cylinder deactivation. The requirement for activation is low load. So, while rpm is higher with a lower final drive, engine load is lower, and thus the is less throttle input for a similar rpm compared to a higher ratio. Slightly increasing rpm, but halving the number of fueled cylinders will increase fuel economy.
I would love to see this same test on whipple trucks with draggy data too.
I’m not sure about the 23’s , but the 24 models have the active air dam to help with aero and increase fuel economy. I have a 24 STX 5.0 3.73 and average 22.5mpg at 70mph
I have a 23 and it has an active front spoiler slash air dam as well 😊
We see this same result in Jeeps with lifts and large tires. The drive ability and fuel economy improves going to numerically higher gears 4.10 to 4.56, 4.88, 5.13 etc... I guess it is the improved mechanical leverage.
The engine may be rotating faster by a couple hundred rpms in each respective gear, but that means the engine doesn’t have to work as hard because the torque is multiplied. Thats why you got better fuel in the 3.73. Just like my truck. I dog mine pretty good and it still gets 15 mpg city. Also the tire swap was a good idea to take away any variables between the vehicles. That being said, the tires from the 3.31 truck may have been a tad smaller than the 3.73 tires, which would explain the computer reading a little higher than it actually got when you measured it at the station. That aside, the measurement at the end is the real deal and the 3.73 truck got almost a whole mile per gallon better and that’s cause of what I said at the beginning of this comment.
It makes sense to me. I have a 16’ 5.0 with the 6 speed and 3.31 gears. You can tell the engine is working harder to get the wheels turning. I think it’s the same concept with those trucks but the 10 speed helps hide it. In theory the 373 shouldn’t struggle as much on the highway with all the hills and wind resistance
Interesting how the 3.31s had better fuel economy on the towing run, but the 3.73s did better unloaded. I would have expected the opposite.
it is very interesting. I personally though both loaded and unloaded would be worse with the 3.73 but not the case.
Is the tire circumference exactly the same? I know you do the same loop, so that certainly helps. But It could be a factor for sure.
If they were 6 speed transmissions then the results would probably follow your thoughts Alex. As stated in the comments bellow, all engines have a rpm range that they sustain torque and efficiency optimization. As a previous instructor on diesel engines for Ford, we would explain the "happy spot" in the RPM range at which a 7.3, 6.0, 6.7 etc... made its peak efficiency. The 3.31 ratio, with the the multiple overdrives of the 10 speed, does not put the 5.0 (1200 RPM) in its best range. The 10 speed transmission really changes which axle ratio makes the engine operation optimal for a given speed. I have 3 new F150s that I am always testing fuel economy on. Two have 3.73 axles and one (Raptor) has the 4.10 ratio. My 2017 F350 6.7 dually, 6 speed, I special ordered with the 3.55 ratio, realizing this reality. Great videos as always. I really appreciate your information and great research efforts.
I appreciate the comment! That raptor with 4.10's with the HO ecoboost is probably stupid fast. but yes it's very interesting how the 10 speed transmission makes all the difference. My conclusion is if you can order higher gear sets with the 5L - do it. you get all the benefits without the fuel economy hit.
No I get 26 mpg in my 2015 at 65 mph on a calm day not gonna get that with 3.73 6 speed
Boi you got a lotta trucks
Well done!.... you did the hard work so we don't have to. My guess is that the 3.73's allow the Coyote to be in an operating range that allows greater use of the cylinder deactivation vs. the 3.31's. Iirc the 3.73's got slightly worse mpg's towing which makes sense given the tow/haul mode disables the cylinder deactivation. Curious as to the max towing ratings 3.31's vs the 3.73's.
Along with what everybody else has said here, another thing could be because you have such a better mechanical advantage at the tire that despite running a higher RPM engine load is lower and so the computer can keep the cams advanced for a longer time resulting in better fuel mileage
Both trucks have similar weights and similar aerodynamics. It should require roughly the same amount of fuel to do the same amount of work. I kind of always suspected that final drive ratio didn't hurt mpg as much as people thought. Now I have seen evidence that might be true in some cases. So it's okay to get the optional gears. Really cool! I'd be interested in seeing if there is a difference between a limited slip differential and a non-LSD. I've heard people claim that it makes a difference. I'm not sure I believe that one.
Have you thought about checking the eco vs normal mode to see if it actually makes a difference on gas mileage?
With a 10 speed transmission, you have so many ratios that choose from the truck can optimize fuel economy, regardless of the rear end. I think the only time you’ll notice a difference is from a stop. You obviously have more torque delivered to the rear wheels very high speeds you’ll keep the RPMs lower. These trucks already run low on the highway. There’s probably no real difference
I just did a 150 mile trip on Sunday in my '24 5.0 SuperCrew with 3.73's. I drove 65 mph, no cruise (I find it hurts more than helps mpg with the surging up hills), almost all highway, and returned 24.7 mpg for that leg. My combined mpg over 3,000 miles so far is 19.0 mpg. These Coyotes are remarkably efficient for what they are, and they sound so good (I have Borla S catback).
totally agree the cruise hurts MPG's going over hills. But for me it's an easy way to keep everything fair. The 5L is a wonderful engine, great power, as you pointed out - sounds great and gets pretty darn good fuel economy.
@@TheGettyAdventures Absolutely agree with using cruise in a comparison test. Eliminates the human variable. Then you're only left to sweat changing wind conditions between test vehicles.
I have 5.0 Coyote Mustang 6 speed manual and 3.73 that gets the same exact mpgs average and highway although I've only done 65 mph once in 11 years. Crazy how a truck can get decent mpgs.
How do you find the cylinder deactivation, does it seem like it helps?
@@garys2157 I'm sure it helps a little, but I haven't done a longer trip in Sport Mode (which deactivates it) to compare the difference. From reading two of the F150 forums regularly, the consensus seems to be that it's a small gain; something like half a mpg or less. At least Ford seems to have designed their system well. There are now four model years of the F150 on the road with cylinder deactivation, and no reports of any lifter issues like GM annd Ram have had with their V8s since adopting the feature.
Unless I am confused, why would anyone buy the 3.31 gears
Naturally aspirated engines running higher rpm getting better fuel economy just means the rotational mass is taking the demand for fuel way down. RPM doesn't always mean load.
It might be 20% load with the 3.73's running 65 mph vs 40% load with the 3.31's running 65.
Couple years ago i made a trip to Atlanta and back starting in illinois with my 19 f150. 5.0, 3.31's cruising along at 62mph keeping it in 9th gear on the interstate, when i got back home it almost hit 29 mpg for the trip. I ran it in 9th gear because in 10th you could feel it loading up which just means it's wanting fuel.
9th gear, rpm up and it felt/sounded like it wasnt even running because there wasnt a load on the engine at that higher rpm.
I’ve always been really happy with the mileage my F150 with the 6R80 transmission and 3:73 gearing gets. I can drive 1000 highway km /610 miles on a tank of gas.
If I’m not mistaken, isn’t the 24 more lighter than 21-23 models? Slightly but not much. I know that ford took off many parts. Great video as well. Also I think the 3.31 is always suffocating during highway miles (I own one) it has to get more gas to feel like you are actually keeping with the speed
I have a 23 5.0 Tremor with the 3.73 and get almost exactly the same as he did under the different scenarios (and I have bigger factory tires and more wieght). I've been pretty thrilled. I think it is just the sweet spot. The mpg was good enough to convince me not to supercharge, which was one of the reasons I bought the Coyote in the first place.
Did you notice that the 3.73 downshifted less with the lower gearing is probably helping the motor hold rpm were the higher gears causes loss of speed and momentum especially on hills and elevation changes
3.73 is lower geared than 3.31
@@davidpotter7484 Thanks for the correction thats what I was trying to write
Maybe Ford should start using only 3.73 gears on all 5.0L F-150’s. I know I love mine!
373 gears are lower gearing. Not higher as you mentioned 331 is a higher gear.😊
The only two things i can think of for the 3.73 getting better mileage is maybe better weather conditions or with the engine having more leverage with the 3.73 gear made it utilize cylinder deactivation more often.
Mechanical Advantage !
YES! The engine spins higher RPMs but takes less gas to hold it there. The engine doesn't have to work as hard because the gears help it out.
i would love to see you do the exact same MPG loop with 2 powerstrokes with the same gears and 10 speed trans...
What year model is each truck? The truck with 3.73 looks like the ‘24 year model.
The only thought I have is since they are new trucks, is the mileage much different between them? I’m thinking if one could be broken in more vs another, that could cause increased MPG.
My 23 tremor has 3:73 and I get almost identical economy to my buddies Ecoboost, but I get better economy while towing, I think the 10 speed is the game changer were the rpm difference is miniscule in 9th and 10th gear
In my 2023 F150 3.5 ecoboost with 3:31s, I get the best fuel economy, at 70mph, in 8th gear, or right at 2000rpms. If I let it shift to 10th, I lose mpg.
probably has to use more boost in 10th gear. my guess anyways.
I think that they are effectively the same adjusted for traffic and temperature.
My truck has the 3.55s, and the temp makes a significant difference. Btw...you can gain 3-4 mpg better by running 62mph.
Under the exact EPA conditions, the 3.31 gears probably come out ahead. probably. In real life, the 3.73 gears get the trans shifting up sooner, and likely keep it in the lean part of the map longer. With 8-10 speed transmissions, I don't think there is a single reason not to opt for the numerically largest gear ratio available. Kudos to Ford and Ram to still let you choose gears. GM only has limited max-tow choices, while Toyota has none.
Running higher gears lets the engine work easier. Its like a generator with no load uses less fuel than when it pulls a load. makes perfect sense what you did. Some with the 5.0 x 3.73 gears in the short bed xl are getting 28 mpg.
the only thing that I could think of that would cause that difference could be some slightly different wind patterns, but that feels like a stretch.
And what he considers city driving is more like suburban driving
I had a 2010 Suburban with 3.07 gears and a 2008 Gmc Sierra with 3.73 gears at the same time. I saw the exact same thing with fuel economy, the 3.73 did better.
Both of these had 5.3 engines with cylinder deactivation that indicated V4 and V8 on the dash. What I noticed was the truck with 3.73 gears stayed in V4 mode a lot more because there was less strain on the engine
I'm guessing that's the same thing that's happening in your test since the 5.0 also has Cylinder deactivation
Time of day matters. Warmer in the afternoon uses slightly less fuel (mixture ratio). Testing needs to be done at the same air temps. Its fractional difference but it adds up. Maybe I am off, but I know mileage is far worse in the winter with cold air temps and better in the summer as I tested.
Not downshifting near as often, actually using 10th gear more often, easier acceleration, etc etc etc. My 10 speed ‘24 tundra with 3.31 gears RARELY EVER shifts to 10th gear as I’m sure the ford with 3.31 does the same but the 3.73 geared truck probably uses it more often.
Are the tires you swapped the same diameter? The Speedo might be slightly off if they’re not the same affecting your km reading.
Alex,these are 2 different model yrs.It could come down to aerodynamics and fuel mapping.I think if you tested the exact same model yr trucks you would come up with a different result
I ordered my last f150 with 3.73 and 5.0 v8, never resetting the trip meter after leaving dealership from day one my over all combined mileage including occasional light towing, 2 winter season morning warm ups in Northern New York, daily driving through down town and a few interstate runs is currently 19.3 mpg at approximately 17000 miles on the odometer, 4 better than my previous 2020 Hemi Ram and 2 better than my previous 2018 5.3 Silverado having not resetting those either 👍
Now THIS is valuable information
My truck with similar specs does about 15mpg BUT I have an ARE construction style topper, bed pretty well loaded down, and is typically hitched with my 22' equipment trailer hauling anywhere between 4-6k. I'm getting roughly the same mpg as my old 5.7 Ram unloaded with no topper.
Any chance you could do a review of the reliability of the new f150s? Like the mechanical side of the undercarriage? I’ve heard bad things about the transmission
Thanks for the video and work effort.
Ford with the 10 speed and 2-3 overdrive ratios 3.73 should be a good choice.
Ram with 3.92 gears and an 8 spd is a different story.
I saw better mileage all around but particularly unloaded on the highway in my 2014 3.92 RAM versus my 2016 with 3.21's (basically same config otherwise). Plus the 3.21's made it feel 1000lbs heavier. I don't know why anyone would select "conventional" gears with these 8 & 10 speeds.
I have 3.92 gears and RPMs are a little higher than I'd like at 70 MPH. I was thinking a higher gear would give me better mileage.
But I agree 3.92 gears sure make the truck quick.
Given the higher trim of the 3.73, does the higher trim get an active aero dam (skirt below bumper lowers over 40mph) but maybe not on the lower trim of the XL/XLT?
Were the wheels the same size?
This has to do with BMEP. The 3.73 has the engine closer to the peak torque. This is why a diesel is better than a gas in the HDs as well. You can do more work with less effort. Torque is the only force and when you have more you can do more. My 6.7 powerstroke with 3.55 get better mileage than the 3.5EB with a 3.55. Even though the 6.7 is 3500lbs heavier and taller. The change of tires offset the computer.
just out of curiosity, was truck mass/weight the same(/nearly so)?
Perfect! If they’d just get rid of the cam phasers, in their 5.0 V-8, I’d buy one
She ain't perfect lol but personally the cam phasers don't worry me that much.
@@TheGettyAdventures still too many horror stories for me, big job repair, body off repair, like owning a modern diesel, terrible
I bought a 2004 F150 4x4 4.6L V8....Came with 3.55 gears...My friend bought same truck after driving mine....But he had 4.10's swapped in and the ECM reprogrammed for those gears. His got better MPG because mine could smell a hill half a mile away and either unlock the converter or would downshift to 3rd... Now the Final drive in OD didn't really change the cruise RPM *THAT* much 2425RPM/75MPH/4.10 VS. 2100RPM/75/3.55 - You would think 300rpm would make worse MPG, but the engine is so outside it torque envelope, that it was "too low RPM" - 80's GM Cars/Trucks/Vans with first generation Overdrives suffered from this too...They geared them like they still had 3-spd autos, but had 30% overdrives. (I had a 1987 G20 TBI 350 with 3.08 Gears and TH700R4, I rarely used overdrive) - Oh and the F150 4.10s pulled trailer (with OD locked out SO MUCH BETTER!)
The coyote 5.0 runs optimally when paired with the 3.73 gears.
The 3.73 gear ratio means the engine doesn't need to work as hard, even if it does turn a little faster. Uses just a hair less fuel as a result.
Your city loop is like my country. I would have hit 500 red lights and stop signs.
Bring that truck to Philly suburbs for a real CITY TEST.
If both have cylinder deactivation perhaps the truck with 3.73 gears runs with the cylinders shut down for a greater % of the time. Dont know if there is any way to determine if that is what is happening.
Saw a V8 F150 for sale with 3.31 gearing. What would that get you, better highway mpg?
It comes down to engine tuning. Engines have a greater BSFC (break specific fuel consumption) at certain engine speeds versus others. I’ve tuned little Yamaha Zuma engines and they were more efficient at relatively higher (but still low) engine speeds. Think 1200-1400 rpm compared to 1800-2000 rpm. We had a lower fuel consumption at the higher engine speeds listed.
Agreed, perhaps the 3.73 gears with the speeds I was driving put the engine in a much better fuel burning range.
@@TheGettyAdventures If you really wanted to know you could do the test again with the 3:31 geared truck and lock out the gears necessary to get the engine speed to be the same as the 3:73. 😆
My explanation would be the 10 speed transmission, which is switching based on engine load.
So if you had the 3.73 at a certain speed in say 6th gear and the 3.31 in 5th gear at the same speed, the 3.73 might have an overall lower gear ratio (transmission ratio * rear axle ratio), resulting in lower engine RPM, and then probably (but not always) better mileage. An additional factor could be, that Ford has developed the shift pattern of the 10 speed best suited to the 3,73 and only did some simple adaptation to the other rear axles.
Every engine has a sweet spot where the peak torque is where the engine will reach its best power/fuel economy.
There's no way that the 3.73 gets 3.5% better MPG vs the 3.31 in those conditions. The RPM's were 10% lower in the 3.31 and with 10 gears, the 3.31 would still be more efficient even it was running in 9th vs the 3.73 in 10th.
Unless he was lying in the video, the numbers tell the story.
The increase fuel economy is due to the higher gearing allowing the truck to run in four-cylinder mode longer. Best fuel economy is achieved with the 3.31 gearing by putting the truck in seventh gear and Eco mode. Aftermarket exhaust as long as you do hear when the truck is in four-cylinder mode and it makes a significant difference for fuel economy.
I interesting, you've tested this ?
@@daveallen7767 yep, I own a 2022 with the 5.0 and 3.31s. 7th gear if Eco mode gets by far the best mileage. The increased RPMs let the truck stay four-cylinder mode.
This is also why the 373s get better mileage. The slightly higher RPMs help the truck stay in 4 cylinder mode.
I've noticed with my 5.4 King Ranch with 3.73 gears that on slight grades my engine won't downshift even when an engine with higher HP would with lower GR.....example....I can climb a hill without downshifting while a Higher gear would be downshifting......and still be at the same speed......another example.....slowing down for traffic and then accelerating again some times they will downshift whereas I don't and maintaining the same speed...BTW the 5.4 is at 199,000 miles.....
I have a 2013 F-150 Platinum 3.5 Eco boost with 3:73 gears. It has the large tow mirrors and Michelins LTX MS tires. I don’t know the weight of the truck. I’m assuming about the same as the 2024. I get 21 highway (70 mph) and 15-16 city. It’s been that way since day one.
Sometimes I think there are better black casting and machining. I’d bet if we took 1000 of the same engines and ran them on the exact same platform we would find significant differences in mileage and actual power.
I have a 5.0 crew with 3.31 gears, and I think 10th gear is at the point of diminishing returns with this rear end.
Larger scale possible? 2.73 vs 4.11?
I'd be curious if the 5.0l doesn't mind extra rpm with the gain in rear gear torque advantage, causing the engine to not actually work as hard
The tires were hopefully the same size on both trucks?
The mpg's are impressive. I'll take the 3:73. Back in the day (the 80's) For example Chevy had 3:42, 3:73,4:10 and 4:56 gears with the 454. My '88 454 Suburban has 3:42, wish it had at least 4:10's. People don't buy those for mpg's. Trucks are for towing, hauling loads and not necessary a daily driver. I am glad mpg's are going up compared to old days. Just my 2 cents Canadian or American, lol...
my original carbureted c20 chevy with a low geared 4.56 and a 3 speed direct drive tranny can get 16.5 mpg on the highway
All engines have a brake specific fuel consumption map. This is a map that shows an engines fuel consumption vs how much power it is making and at what RPM. If you are driving the same speed down the same road, like in this 85 mile loop, the power required is basically the same. However, as mentioned, the engine RPM is different. It's a common misconception that lower RPM automatically = lower fuel consumption. If you look at those fuel consumption maps, the most efficient spots are usually 1500-2500 RPM. If it takes 35 hp to run the truck down the road at 60 mph, at only at 1100 RPM, it's not surprising at all that it may be more efficient at 1400 rpm.
I had a manual transmission X3 that had 3.90 gears. I installed the 4.4 gears out of the automatic version. It would do almost 4k rpm at 80 miles and hour and the fuel economy did not change at all.
The difference comes down to where the torque comes in at.