Re-gear from 3.73 to 5.13

[ndesantis]

new to the forum. new to the jeep community also. never owned a jeep until recently. purchased a 2025 gladiator in december bone stock from the dealer. went right to town with upgrades and did a 2.5 inch lift and paired it with 17inch black rhino arsenal wheels as well as 37 inch mickey thompson baja a/t tires. i had a reputable shop near me do all the work and i couldn’t be happier. they also did fox shocks with the lift and all new upgraded steering components.

i am currently lagging with the stock 3.73 gearing. the truck struggles to find 6/7/8th gears on the highway at mid speed. no power at all when trying to get around another vehicle. i absolutely have to drive the truck in manual mode to avoid the trans struggling to find what gear it should be in.

i ordered 5.13 gearing and i am awaiting the shops call to have it installed. i was borderline 4.88 gearing and i pulled the trigger on the 5.13 instead.

looking for any comment on someone who went from 3.73 to 5.13 and what you like/do not like about the gear change or if you regret not doing 4.88 instead.

purchase has been made so no going back at this point. i’m more or less looking for reassurance that i made the correct choice.

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[azmojave]

All the feedback I’ve read is some 4.88 people wish they went 5.13, not the other way around.

 

[whysoserious]

 

[Jteakus]

5.13, don't look back.

 

[DanJT]

What am I missing? I have went with 37" KO2's and I have plenty of power to get up and go!! I even have to be careful to not give it to much gas because it will spine the tires when trying to pull out in traffic.. Oh and I believe the Diffs are stock 4.10'S... Bought it new!

 

[NC_Overland]

What am I missing? I have went with 37" KO2's and I have plenty of power to get up and go!! I even have to be careful to not give it to much gas because it will spine the tires when trying to pull out in traffic.. Oh and I believe the Diffs are stock 4.10'S... Bought it new!

Two things. One is 3:73 vs 4.10 and the other is the actual tire. If you’re running say BFGs, they run really small and are light. 37s are almost 35s with them.

 

[DanJT]

Two things. One is 3:73 vs 4.10 and the other is the actual tire. If you’re running say BFGs, they run really small and are light. 37s are almost 35s with them.

And with that said I still can Bark the tires at take off, And with that I 3D printed KO'2 for a Koozie..

 

[NC_Overland]

And with that said I still can Bark the tires at take off, And with that I 3D printed KO'2 for a Koozie..

Yeah, the deep first gear helps a lot. I can lay pretty solid 11s on 3.73s and 34s and some people say you can’t do that.

 

[DublF]

I was in the exact same boat 2 years ago. Went with Revolution 5.13's. Not one regret. Good luck.

 

[Sweetums]

The question of gearing depends a lot on your environment and if you're running a Dana 44 axle; if you're in an environment that's slippery, muddy, or has loose soil then there's no real problem with the 5.13 gears and a Dana 44. If you are in Moab or other environments with very high traction and potential driveline binding, 5.13 gears become a problem. The small pinion gear means less engagement with the ring gear and tends to result in broken teeth and sheering. I've seen more than a few diffs grenade on the slickrock, but 4.88 gears have a larger pinion and more surface area engaged with the ring gear.

If you go with a Dana 60, all this above is meaningless since you can get 5+ gearing ratios out of a larger ring gear and keep a larger pinion for more engagement.

 

[Bandit’s Lair]

The question of gearing depends a lot on your environment and if you're running a Dana 44 axle; if you're in an environment that's slippery, muddy, or has loose soil then there's no real problem with the 5.13 gears and a Dana 44. If you are in Moab or other environments with very high traction and potential driveline binding, 5.13 gears become a problem. The small pinion gear means less engagement with the ring gear and tends to result in broken teeth and sheering. I've seen more than a few diffs grenade on the slickrock, but 4.88 gears have a larger pinion and more surface area engaged with the ring gear.

If you go with a Dana 60, all this above is meaningless since you can get 5+ gearing ratios out of a larger ring gear and keep a larger pinion for more engagement.

This is why I’ll stick with 4.88. No Likey grenades under the Jeep.

 

[ndesantis]

What am I missing? I have went with 37" KO2's and I have plenty of power to get up and go!! I even have to be careful to not give it to much gas because it will spine the tires when trying to pull out in traffic.. Oh and I believe the Diffs are stock 4.10'S... Bought it new!

i have a willy’s edition they come stock with 3.73 so im really feeling the lag lol. you’re lucky you have that kind of power without having to re gear. do you have a banks pedal monster? that’s helped me out a bit but it’s far from the solution lol

 

[ndesantis]

The question of gearing depends a lot on your environment and if you're running a Dana 44 axle; if you're in an environment that's slippery, muddy, or has loose soil then there's no real problem with the 5.13 gears and a Dana 44. If you are in Moab or other environments with very high traction and potential driveline binding, 5.13 gears become a problem. The small pinion gear means less engagement with the ring gear and tends to result in broken teeth and sheering. I've seen more than a few diffs grenade on the slickrock, but 4.88 gears have a larger pinion and more surface area engaged with the ring gear.

If you go with a Dana 60, all this above is meaningless since you can get 5+ gearing ratios out of a larger ring gear and keep a larger pinion for more engagement.

this is where i get a little mixed up and not sure if i made the correct choice. i have Dana 44 and will be trail riding the jeep as well as riding the beach. in jersey the beaches are generally super loose and deep sand. in these instances i suppose the 5.13 is great. but regular highway driving and getting around town seems like 4.88 is a better choice. last thing i want is future issues because i chose the wrong re gear. maybe im being too technical about it.

 

[VA6489]

It is a trade off for power, fuel mileage and reliability. 5.13 will give you that pounce you are looking for but remember the 3.6 motor is happy at 4000 RPMs. This will also impact you highway fuel mileage.

Running sand, 4 Lo is the right choice easy on the throttle and obviously air down a lot.

There is a reliability issue with the 5.13 as described above. If you don't beat it likely will live a long time. If you are a Throttle out kind of guy..... make friends with a tow truck company.

 

[ndesantis]

being inexperienced with this gearing change kinda sucks. so much to read online and i’ve read great things about both gearing choices. my biggest concern was wanting the truck to feel stock again. on highway rides 6th gear is the highest the truck will get in auto. i’ve read 4.88 still not that “stock” feel with 37s

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