Anyone go with 5.13 or 5.38 gears on 37’s and still daily the Bronco?

[Snacktime]

If your worried I would increase the oil change interval and go synthetic. Your not going far enough from factory optioned 4.71 to be in uncharted water. I wouldn't expect to get more than 75K miles out of the 5.13/5.38 gears. Biggest thing is knowing your going to be doing gears again if you plan to keep it 100K miles.

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[EMBronco]

Does the m210 you've got have the 4.70 gearing? I run 37's with 4.70 gears and feel like it's about a perfect middle ground for offroading and daily driving.

 

[lapazleo]

I would go with spicer gears and you shouldn't have any issues. Biggest issue with that much gearing is making heat in the differential so no stupid loads towing.

Higher gear ratio number = equals lower gearing therefore less stressful towing lower heat.

 

[lapazleo]

If your worried I would increase the oil change interval and go synthetic. Your not going far enough from factory optioned 4.71 to be in uncharted water. I wouldn't expect to get more than 75K miles out of the 5.13/5.38 gears. Biggest thing is knowing your going to be doing gears again if you plan to keep it 100K miles.

Gear ratio has zero to do longevity.

 

[Snacktime]

Gear ratio has zero to do longevity.

Has everything to do with longevity.

 

[BigMeatsBronco]

Most of the people going up that high are going to have specialty rigs. That's kind've the reason to do it.

Or big enough meats to ballance out the 5.38s...my rpms at 60 is nearly the same as 315s and 4.7.
And I drive mine daily, not trailering the bronco!, I did tow a travel trailer to Moab on 40s....fuel economy does suffer (mostly from the tire size)

 

[BigMeatsBronco]

Has everything to do with longevity.

plenty of semi trucks getting 1-2 million miles on 5.38s...its not the miles but the case spread/gear deflection that ruins them...same with the jeeps. the case spreading is exaggerated with lower gear ratio like 5.38 in the m220 because the pinion has more leverage against the ring gear.

 

[Snacktime]

plenty of semi trucks getting 1-2 million miles on 5.38s...its not the miles but the case spread/gear deflection that ruins them...same with the jeeps.

Yes and the pinion size is much larger in a commercial application. In these smaller axles the pinion is substantial smaller and lower gear shrinks the pinion causing more wear. Your losing surface area, more wear on the surface from higher forces. It's a losing game! In Toyota land 4.88 was the magic gear ratio that survived long term, lower and the life was much shorter.

 

[Techun]

This is from my Bronco with the 2.7, 5.13 gearing, and 38 Nitto TG's. 74 MPH at 2,300 RPM. I would recommend the Ford ProCal Tuner, it makes the shift points perfect. I am not positive, but I think you must have it when changing the gearing anyway. It's a great daily driver with no issues. I have never checked fuel economy so I don't have any info on that.

Judging by your miles to empty you're getting around 12 mpg

 

[‘21OBX]

Does the m210 you've got have the 4.70 gearing? I run 37's with 4.70 gears and feel like it's about a perfect middle ground for offroading and daily driving.

It does but is need if a rebuild and I have 4.27 gears stock. Which I really like. Has done well off road. Having a hard time locating 4.27 gears for the m210

Or big enough meats to ballance out the 5.38s...my rpms at 60 is nearly the same as 315s and 4.7.
And I drive mine daily, not trailering the bronco!, I did tow a travel trailer to Moab on 40s....fuel economy does suffer (mostly from the tire size)

not going 40’s at least until these 37’s wear out. They are heavy tho. The wife has already mentioned going to 40’s tho so if I’m adding the m210 I’d rather only have to pay to re gear once. That’s one reason to jump into the 5’s.

 

[KermitBronco]

Early '23, I checked in with Zack Heisey at Dana and he strongly suggested 4.88 for 37's when we upgraded to Ultimate 44 FDU. Two months later, I was doubly grateful for his advice because when we added the Dana 60 rear, we were okay. The 60 only comes in a few sizes and it jumps from 4.88 to 5.38 (no 5.13 which is FDU option). I'm super happy with how the rig drives.
The only "challenge" is rock crawling w/ the 44 FDU, Spicer Xtreme splines and Trail Grapplers, it is near impossible to steer at all with the front locker on. You are PLANTED.

 

[BigMeatsBronco]

It does but is need if a rebuild and I have 4.27 gears stock. Which I really like. Has done well off road. Having a hard time locating 4.27 gears for the m210

not going 40’s at least until these 37’s wear out. They are heavy tho. The wife has already mentioned going to 40’s tho so if I’m adding the m210 I’d rather only have to pay to re gear once. That’s one reason to jump into the 5’s.

If the wife suggests 40s, she like the bigger meats look (and function too) I highly recommend listening to her ...(This time)

 

[One more upgrade]

Judging by your miles to empty you're getting around 12 mpg

Yes, around town, I get 11 to 12 MPG. I very rarely do freeway driving, so I cannot provide accurate data for commuting with 5.13 gearing.

 

[Gtrekker]

Hello planning a re gear and adding a locking FDU M210. Just wondering if it’s still decent to drive around as our bronco is still driven daily. How big of a hit to mpg if any. We have the auto transmission. Been on 37’s for 20k miles with no issues on the 4.27 gears. Have ran into multiple time where I couldn’t get up an obstacle that a front locker would help with. But I don’t want to make the bronco unpleasant to drive daily.

I run 37" K02s as a daily driver and hit mud, rocks n sand for iff road fun. My factory gears work well, no issues and don't plan to change until I go to 40"s.

 

[‘21OBX]

I run 37" K02s as a daily driver and hit mud, rocks n sand for iff road fun. My factory gears work well, no issues and don't plan to change until I go to 40"s.

By your logo you have a wildtrak correct? So you have 4.7 gears.

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