Thoughts on F-150 Axle Ratios

[pjb]

373 ESPECIALLY IF YOU PLAN ON LARGER TIRES

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[KBKEITH]

3.73 on my 5.0 and I love that pull!! I wouldn’t change them.

Yep. 3.73 with the 2.7. Comes out of the hole quick and strong.

 

[Knickell]

I wen


I went with the 3:31 e-lock on my Reg Cab, Short Bed XLT coyote. I have an hour and a half freeway commute (not that I plan to use it for commuting much) and most of my towing will be at low speeds on dirt roads in 4x4 so I don't think torque is going to be a towing issue for me. With the 122 wheel base I'm already 1000lbs ahead of the game on asphalt city driving.
I expect to get delivery of my truck sometime in the 21st century so I'll post how it worked out once I can.
...if we're still using the internet by then!

I’d say a 21st century delivery is still a pricey bet at this point....

 

[HDT05]

Mine is still running in (less than 1000 miles) on my 5.0 with 3.73.... but I was surprised to see the other day that I was doing 47 mph @ 1200 rpm....

It's getting around 16 mpg at the moment (although my wife has a FAR heavier right foot than me ) so don't know the true mpg... lol

 

[Knickell]

Loving my 3.55 gears so far. Averaging 5 miles per gallon so far, but the truck only has seventy miles on it, so hopefully it’s just the trip computer getting itself oriented!!

 

[SuvE]

You can clear the average from the delivery process. Zero it out and start from now. That will give you a much better indication without including old data.

 

[daemonic3]

Loving my 3.55 gears so far. Averaging 5 miles per gallon so far, but the truck only has seventy miles on it, so hopefully it’s just the trip computer getting itself oriented!!

I think someone used your generator for a tailgate party!

 

[Knickell]

I think someone used your generator for a tailgate party!

I’ve only got the gas EcoBoost, they would have to have been using my lowly single 400W outlet in the bed!

 

[daemonic3]

I’ve only got the gas EcoBoost, they would have to have been using my lowly single 400W outlet in the bed!

My bad, I figured you had the 2kW genny.

Well, that totally ruined my joke!

 

[Vulnox]

One thing I noticed with the EB engines and the 10 speed, at least for the 2018-2020 trucks, is you may do worse on fuel mileage with an EB and 3.55 or 3.31 than a 3.73 because on the freeway in 10th gear, the truck seems to prefer to give you boost instead of raise RPMs if there is increased load (like slight incline or head wind). When it adds boost the freeway MPG suffers. I know in a discussion for that gen some noted that they actually saw better fuel mileage on the highway if they locked out 10th gear, forcing the truck to sit at a very slightly higher RPM, but no boost.

I did a test on my drive to work. For one week did normal everything, no lock out, cruise control at 70, etc. It's only about five miles or so that I am on the freeway, but it's a steady drive. My fuel mileage WAS about one MPG better the next week when I locked out 10th gear, consistently, compared to the previous week. No significant changes in weather or traffic or anything. My 2019 has 3.55 gears, and a 2.7L. I suspect a 3.73 would have been enough RPM in 10th gear that it wouldn't have shown as much if any benefit, but who knows.

Now they may have improved the engine logic for 2021, I am sure they have, but overall the drivelines are fairly similar in the 2.7L and 3.5L EB, 10 speed trans still, same rear end gearing offerings. So it's possible that 10th gear anomaly may still exist to some extent. I am hoping that being on the 3.73 will eliminate it.

Even if that exact issue isn't there, I still believe based on years of driving EB vehicles, that anything that keeps you out of boost and uses normal engine RPM, to an extent, is going to help your efficiency. Conversely, I would expect the 3.3L and 5.0L to do better with the 3.31 as expected. I think the boost engagement just adds an extra layer of complexity to figuring out best efficiency.

 

[Knickell]

My bad, I figured you had the 2kW genny.

Well, that totally ruined my joke!

Funny story with that.

I deliberately did not get the 2KW ProPower on board because I wanted the under seat fold flat locking storage. (Because of the inverter under the seat, it kept you from gettin both on a gas only truck)

My sales rep. sent me a video of the truck once it arrived. In the video, I noticed an outlet in the bed.

Panicking thinking they built it with ProPower and not my storage I reviewed my window sticker and couldn’t find the lockable storage option anywhere (it was there, I was just so upset initially, I overlooked it)! I literally began to feel nauseous having waited this long and believing my truck was built wrong.

My sales guy FaceTimed me and showed me that the lockable under seat storage was, in fact, there and told me that the outlet in the bed was standard on all 2021s. That is one of the few things I was fortunately wrong about.

I was expecting the bed to not have any outlets. The one 400W is a nice bonus!

Such a roll coaster of relief once I saw the storage was actually there AND the outlet in the bed!

 

[daemonic3]

One thing I noticed with the EB engines and the 10 speed, at least for the 2018-2020 trucks, is you may do worse on fuel mileage with an EB and 3.55 or 3.31 than a 3.73 because on the freeway in 10th gear, the truck seems to prefer to give you boost instead of raise RPMs if there is increased load (like slight incline or head wind). When it adds boost the freeway MPG suffers. I know in a discussion for that gen some noted that they actually saw better fuel mileage on the highway if they locked out 10th gear, forcing the truck to sit at a very slightly higher RPM, but no boost.

I did a test on my drive to work. For one week did normal everything, no lock out, cruise control at 70, etc. It's only about five miles or so that I am on the freeway, but it's a steady drive. My fuel mileage WAS about one MPG better the next week when I locked out 10th gear, consistently, compared to the previous week. No significant changes in weather or traffic or anything. My 2019 has 3.55 gears, and a 2.7L. I suspect a 3.73 would have been enough RPM in 10th gear that it wouldn't have shown as much if any benefit, but who knows.

Now they may have improved the engine logic for 2021, I am sure they have, but overall the drivelines are fairly similar in the 2.7L and 3.5L EB, 10 speed trans still, same rear end gearing offerings. So it's possible that 10th gear anomaly may still exist to some extent. I am hoping that being on the 3.73 will eliminate it.

Even if that exact issue isn't there, I still believe based on years of driving EB vehicles, that anything that keeps you out of boost and uses normal engine RPM, to an extent, is going to help your efficiency. Conversely, I would expect the 3.3L and 5.0L to do better with the 3.31 as expected. I think the boost engagement just adds an extra layer of complexity to figuring out best efficiency.

I had similar results towing in 7th vs 8th gears, you may have seen it here: https://www.f150gen14.com/forum/thr...first-hookup-and-test-results.2698/post-40096

My question for experts, what is a safe RPM to travel in for multiple hours? I don't know if 2.3kRPM is safe on engine heat, to gain the extra 2 MPG while towing. I don't know your RPM's in 9th vs 10th, what were you seeing? I haven't done any freeway driving this past week to experiment with unloaded driving.

 

[UNIKRN150]

You can clear the average from the delivery process. Zero it out and start from now. That will give you a much better indication without including old data.

I'm "old school"...
Fill it, run it dry, fill it again and do the math.

 

[daemonic3]

I'm "old school"...
Fill it, run it dry, fill it again and do the math.

That takes over 600 miles to empty before you can fill, then another 600-700 to run dry again! We need an indicator much sooner than that...

 

[Don]

You don’t have to run it dry, just record the miles driven and number of gallons to bring back to full and do the math, miles/gallons. You are not relying on the vehicle computer system to do the figuring.

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