I'm building my 2020 F150 5.0 V8 4x4 truck. What's better for towing a 3000lb boat. 3.31 non limited slip or 3.55 Electronic locking axle ratio? Thanks

 

3.31's will do it just fine, but i'm not sure why you'd turn away 3.55's with the locker.

 

3.55. 3.31 are highway gears for fuel economy, but leave a lot to be desired when towing, even WITH the 10 speed.

 

^^^^^What he said^^^^^
& I'll add just from what I've read here on the forums about locking out the top 2 gears when towing....You could even go 3.73 & it would pull even better!!
Also if operating in hilly terrain the higher ratio gear would do much better!!

 

The 3:31 mated with the 10-speed is lower than one would believe when thinking 3:31.
I'd opt for the 3:55 if it were me but if I bought a truck with 3:31 and only towed 3,000 lbs I wouldn't even blink.

The transmission is geared lower than the 6 speed was and the ratio is closer, one can more easily hold power.

10th gear is lower than 6th was. Not hugely overall, but it's between a 3:31 and 3:55 of a 6 speed transmission.

If you plan to increase tire size, don't order 3:31.
However, if you love driving long distances and only plan to tow that boat, 3:31 will will cheaper overall.

 

Only downside of 3.31 and 10 speed is it will hunt more where the 3.55 will stay in a higher gear when going up and down hills. They will tow fine, but at lower gears.

 

I disagree, just from experience. But...I have the 3.5 ecoboost so that may be a differentiator.

 

A 3000lb boat is nothing for an F150, regardless of gearing. If fuel economy is important to you, I'd go 3.31. If not, or if you think you may tow something heavier someday, get the 3.55.

 

In the 5.0 you want 3.55's and 3.73's would be better. Getting the torque at lower rpm helps the 3.5 EB get by with 3.31's. But I'd still much prefer 3.55 even with the 3.5. Even with just a 3000 lb load. Sooner or later almost everyone hitches up to something a little heavier and you'll wish for lower gears when you do. Where you tow matters too. At sea level in Florida you don't need the same power that you'd need at 11,000' on a 7% grade in Colorado.

 

I special ordered a 2020 with the 5.0, and I would've went with 4.10's had they offered it to be quite honest. And I don't even tow.

I did go with the 3.73 E-locker, which on my particular truck did give me the bigger 9.75" axle 'free of charge'.

I understand not all models are available with the 3.73's, so 3.55's would be the next best thing. I can imagine myself only using the E-locker under the most grueling off-road situations, which wouldn't be very frequently.

The way these transmissions are geared, 3.31 gears are really too high for anything other than the German Autobahn, IMHO.