4.88s or 5.13s

[Gladiator85]

Have a 23 Gladiator Rubicon. Currently have 295/70 R17s 33.5. Looking to go either 305/70 or 315/70s down the road. With 4.88s at 75 I'll be turning 2350 vs 2470 at 75mph with 5.13s and current size. Anyone with experience on either?

Sponsored

 

[Gladiator85]

Chart

 

[Gvsukids]

Have a 23 Gladiator Rubicon. Currently have 295/70 R17s 33.5. Looking to go either 305/70 or 315/70s down the road. With 4.88s at 75 I'll be turning 2350 vs 2470 at 75mph with 5.13s and current size. Anyone with experience on either?

https://www.jeepgladiatorforum.com/forum/forums/transmission-axles-and-gears.25/

 

[Reddog]

I assume you have 4.10's currently. Why do you want lower final drive gears? You didn't say. With 33's, 4.10's and an eight-speed transmission are fine. Just curious.

 

[MudderNuker]

I'm running 35x12.5 with 4.10s and didn't feel much difference and I live in the mountains at over 7,000 ft. in elevation. Only while towing you notice a slight lack of oomph at take off. It still tows well. I see 8th frequently on highways. In my opinion, unless you are going with 37s in the future, regearing for 35s is not necessary.

 

[Badweather]

I run 37" tires and 5.13 gears and could not be happier

 

[KevinM60]

From what I've read on this forum you can go up to 35s and the 4.10s will still be good. When you go up to 37s you would want to regear to 4.88s or 5.13s.
I went from 33s to 35s with 4.10s and no real difference that I could tell.

 

[xcd]

5:13 and don’t look back. Just look forward to being able to run 37’s cuz that day will come.
I run 5:13 with 38’s and it is perfect (IMO).

 

[Krobarr]

Some food for thought!
I was running 37’s on my old Gaser and went 5.13’s and towed my trailer weighing 5,200 dry and blew up my rear end on a trip to a family reunion, limping into the campground. If you’re towing, 4.88 would be the better choice. When I upgraded the gears, towing wasn’t something I’d thought much about.

 

[Wheelin98TJ]

Some food for thought!
I was running 37’s on my old Gaser and went 5.13’s and towed my trailer weighing 5,200 dry and blew up my rear end on a trip to a family reunion, limping into the campground. If you’re towing, 4.88 would be the better choice. When I upgraded the gears, towing wasn’t something I’d thought much about.

I don't think your issue was caused by running 5.13 instead of 4.88.

There are a ton of people running 5.13 with no issues.

 

[pcrawfordpt]

I went with 5:13 gears for my 37’s.. They are perfect. I also have a set of 35’s that I run for towing the camper. I can tow with the 37’s, but it’s just a little easier through the mountain passes with the 35’s. Even when not towing with the 35’s it still runs fine down the highway…no huge RPM spike, but probably less MPG. I’d say go 5:13 if you think there’s any chance you might get 37’s at some point. If you’re sure you won’t ever go up to 37’s then stick with 4:88.

 

[RangerG]

Mine JTR is going in for 5:13 gears. Looking for that better performance on the highway (8th gear) and better performance off-road. Been running 4:88 for two years now on BFG KO 2 37x 12.5x 17. Its ok. Wish I would have done 5:13 from the beginning. I did get a good deal on re-gear and cormoly axel shafts

 

[Krobarr]

I went with 5:13 gears for my 37’s.. They are perfect. I also have a set of 35’s that I run for towing the camper. I can tow with the 37’s, but it’s just a little easier through the mountain passes with the 35’s. Even when not towing with the 35’s it still runs fine down the highway…no huge RPM spike, but probably less MPG. I’d say go 5:13 if you think there’s any chance you might get 37’s at some point. If you’re sure you won’t ever go up to 37’s then stick with 4:88.

Interesting idea, never thought of that. More expensive but far easier on the Diff!

 

[pcrawfordpt]

Interesting idea, never thought of that. More expensive but far easier on the Diff!

Just the price of the wheels, but the improved MPG towing, decreased strain on the system, and the feeling of well being, I feel it's worth it. Besides, the tires last twice as long this way, so you are buying them at a lower price now compared to a year(s) from now. The wheels on the 35's stay looking nice, as the 37's are are full of rock rash etc. I can/do wheel on the 35's, just not the really hard trails. The only issue is swapping them out and keeping track of the rotation schedule...had to make a spread sheet...lol.

 

[Gladiator85]

Jeep doesn't hold 8th unless no hills or wind. I want 100% full use of 8th gear. No reason to live in 7th when you have an 8 sp.

Sponsored