Which gearing for differental?

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Dec 21, 2018 | 04:27 PM

garan

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Which gearing for differental?

Going to order a new F150 this summer. 5L engine with 10 speed trans. Which gearing for the differential, 3.55 or 3.73? Also thinking of getting the electronic locking axle. Anyone having problems with them? Live in western Montana with hills and mountain passes, can have some deep snow in winter. Only pull a utility trailer with 4 wheelers or snowmobiles. Will be used a lot on back country roads when out hunting. I appreciate any input and suggestions. Thanks. Garan

Dec 21, 2018 | 05:19 PM

glc

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From: Joplin MO

3.55 should be sufficient and will get better gas mileage. Definitely get the e-locker or a limited slip.

Dec 22, 2018 | 03:32 AM

Fifty150

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From: The Barbary Coast

I agree with 3.55. 3.73 will decrease mileage, with very little gain. Most people do not consider 3.73, but instead, regear to 4.10. I use 4.10 with 35" tires.

Dec 22, 2018 | 08:06 AM

ManualF150

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From: Vernon, NY

I've got 4.10s in my F150 with stock tires. Way better than 3.55.

Dec 22, 2018 | 10:55 AM

glc

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Big difference between your manual transmission 4.2 V6 and a 10 speed automatic 5.0 Coyote.

Dec 23, 2018 | 12:08 AM

Fifty150

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From: The Barbary Coast

Huge difference

Dec 25, 2018 | 12:46 AM

Patman

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My 2018 came with 3.15 axle. Kinda wish I had 3.55s

The 3.15s are great for highway mileage as long as its completely flat. Get into an incline and it wants to drop to 8th to pull a hill

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Dec 25, 2018 | 10:09 AM

tuckr2

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From: Puyallup, Wa

Quote:

Originally Posted by garan

i don’t believe you can get 3.73 gears unless you also add HDPP (heavy duty payload). I have a 2018 s/crew with max tow which comes with 3.55 gears and FX4 package which I believe add electronic locking differential. While mine is a 3.5 v6 the 5.0 will also do well in Montana comparably equipped. Went through Montana about a month ago. The 10 speed really helps and is geared such that the 3.55 is more comparable to 3.73 with the 6 speed transmission. Additionally, speeds in Montana freeways will eat extra gas with 3.73. Gearing from 3.55 will work very well for your choice.

Last edited by tuckr2; Dec 25, 2018 at 10:13 AM.