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Upgrading to 4.88 Gears

Dilly’S Willy

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On 32”? You could probably do some wicked 4 wheel burnouts. :CWL:
Yeah, I know I'll need to regear for the weight increase and larger tires form 3.73 on the manual. But I'm trying to do the regear and diff upgrades at the same time. I know I'll be adding weight before the regear and have 32s that probably won't wear out before the 34s are needed, so I'm asking about 4.88s since I don't think 4.56 will give me the powerband the 4.88 will for the hilly area I live around and the increased weight/towing/possible lift factors.

4.56 would be fine if I didn't plan on towing/hauling or lived in a flat area. But I'm not sure if they will perform as well as 4.88 will. I'd rather spin 2800rpm vs 2100rpm in 6th until I get 34s since I rarely use 5th gear even on the highway here. 6th gear is a joke, even on long trips with 3.73s on 255/75r17 MTs.
 

Bandit’s Lair

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For temporary yeah you should be fine. 4.88 is a pretty good gearing all around for hilly areas. I have it on mine with 37” and it’s just shy of being a really good gearing. Not enough of an issue to spend the cash to go to 1 step higher and I eventually want to go to a 5.7 and moving up to 38” so leaving it as is. I have around a 2k’ elevation climb from town to the house and I see 6th for a good portion of it once she gets going. For reference I start at @1955’ at a stop/turn and climb to @ 3922’ within 7 miles or so.
 

Jrgunn5150

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We've had 4.88's with stock 32's for almost two years.

Still goes 85 mph down the highway, still is slow AF, definitely doesn't do any wheel burnouts, no one is dead, nothing has exploded, my cam shafts are fine.

Will probably step up to 35's in the fall since I have cool new beadlocks
 

Stan H

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Yeah, I know I'll need to regear for the weight increase and larger tires form 3.73 on the manual. But I'm trying to do the regear and diff upgrades at the same time. I know I'll be adding weight before the regear and have 32s that probably won't wear out before the 34s are needed, so I'm asking about 4.88s since I don't think 4.56 will give me the powerband the 4.88 will for the hilly area I live around and the increased weight/towing/possible lift factors.

4.56 would be fine if I didn't plan on towing/hauling or lived in a flat area. But I'm not sure if they will perform as well as 4.88 will. I'd rather spin 2800rpm vs 2100rpm in 6th until I get 34s since I rarely use 5th gear even on the highway here. 6th gear is a joke, even on long trips with 3.73s on 255/75r17 MTs.
You regear to 4.88 and 6th gear will be right back there is a guy in here who did a video with a side my side comparison of 2 manual gladiators one 5.13 one 4.88s both pulling 6th like a champ.
 

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Onebadv2

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Local 4wd shop is going to do a 4.88 regear on my’21 sport. Recommendations are to come back in 500 miles for lube flush and replacement. Easy enough for the rear but I’ll never get 500 miles on the front. Anything I should do specifically for the front since I won’t ever meet the break in mileage?
 

Bandit’s Lair

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Local 4wd shop is going to do a 4.88 regear on my’21 sport. Recommendations are to come back in 500 miles for lube flush and replacement. Easy enough for the rear but I’ll never get 500 miles on the front. Anything I should do specifically for the front since I won’t ever meet the break in mileage?
Wheel the snot out of it. Even if you don’t reach that 500 miles for the front by the first flush it will have some break in. The first few miles are where you’re going to see the most break in stuff come loose. 4.88 it shouldn’t be horrible. Try to gauge how many miles are on the front and have the shop do both but when you hit that 500 on the front go ahead and change it out yourself. Just for that warm fuzzy feeling.
 

Jrgunn5150

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Local 4wd shop is going to do a 4.88 regear on my’21 sport. Recommendations are to come back in 500 miles for lube flush and replacement. Easy enough for the rear but I’ll never get 500 miles on the front. Anything I should do specifically for the front since I won’t ever meet the break in mileage?
Never did a thing with either end but go drive.

Three years and 68,000 miles ago now.
 

JTGuy

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Ask them for the REM polish and it will simplify the break in process.
 

Stan H

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Local 4wd shop is going to do a 4.88 regear on my’21 sport. Recommendations are to come back in 500 miles for lube flush and replacement. Easy enough for the rear but I’ll never get 500 miles on the front. Anything I should do specifically for the front since I won’t ever meet the break in mileage?
The front does not have the same stress load on a typical basis . Just go do some light off roading , forest service roads easy trails where you can kick it in 4wd. Do that for several trips and it will be good to go . Then change the diff fluid after 500 .
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