Regearing a manual transmission Sport S to 4.56

willcasp

Well-Known Member
First Name
William
Joined
Jun 23, 2019
Messages
280
Reaction score
153
Location
Bothell, WA
Vehicle(s)
2018 JLU Sport S
Thank y'all for all the posts. I have done some research, and it looks like 4.56 for my 35" (actually, measure at 34") tires is the right application for what I am doing. Mostly highway, and some forest service road duty.

Are there any gear kits to avoid? I am looking at the one from Nitro Gear and Axle. I will have them professionally installed.





Advertisement

 

fdFifty

Well-Known Member
Joined
Dec 19, 2018
Messages
81
Reaction score
70
Location
Pittsburgh
Vehicle(s)
2019 Jeep Wrangler Sport
I think you'll be really happy with the 4.56's and the MT. It's a solid setup, even if you decide to do some more technical trails down the road. I'm glad I didn't go any lower because first would be too deep for daily driving and you'd need to gear really low to make starts in 2nd consistently viable.

I had G2 gears installed in mine and I'm not sure if i'm super happy with how they've broken in. Lots of metallic content in my last diff oil change. Currently working with the local 4x4 shop to see if the set needs to be replaced or not. Really hard to say if mfg quality has anything to do with it, but that's my experience the G2 set so far.
 

rustyshakelford

Well-Known Member
Rock Sponsor (Level 1)
First Name
Brett
Joined
Sep 14, 2018
Messages
2,371
Reaction score
2,697
Location
Navasota, TX
Vehicle(s)
2019 JLUR-8 speed 2020 F-350
I went 4.56 with 35's and the 8 speed auto. It is perfect. I believe you will need 4.88's with the manual. I am sure others will chime in.
I agree, with the manual, the 4.88s are a great pair with 35s

Brett
 

Jeepjunkie

Well-Known Member
First Name
Eric
Joined
Dec 17, 2018
Messages
331
Reaction score
328
Location
Annapolis
Vehicle(s)
2019 JLU Sport
Vehicle Showcase
1
I have 4.56s with 33s and plan to go to 34s or 35s. It’s a great set up, about 2500 revs at 72-75mph. I have Yukon gears and they’ve been great: quiet and very little metal in the gear oil.
 

Boutch76

Well-Known Member
First Name
Yannick
Joined
Oct 15, 2019
Messages
116
Reaction score
107
Location
Vancouver
Vehicle(s)
2018 Jeep Wrangler Sport JL 2D Manual
I have 4.56s with 33s and plan to go to 34s or 35s. It’s a great set up, about 2500 revs at 72-75mph. I have Yukon gears and they’ve been great: quiet and very little metal in the gear oil.
Did you have to change your front differential carrier. A shop a contacted told me I should change both the front and back, but with the trac loc anti spin rear differential I dont need to change the back.
 

Jeepjunkie

Well-Known Member
First Name
Eric
Joined
Dec 17, 2018
Messages
331
Reaction score
328
Location
Annapolis
Vehicle(s)
2019 JLU Sport
Vehicle Showcase
1
Did you have to change your front differential carrier. A shop a contacted told me I should change both the front and back, but with the trac loc anti spin rear differential I dont need to change the back.
I swapped in a whole new front axle (Prorock 44), but I didn’t think the carrier needed to be changed in the stock axle.
 

DanW

Well-Known Member
First Name
Dan
Joined
Mar 2, 2017
Messages
6,410
Reaction score
7,546
Location
Indiana
Vehicle(s)
18 JLUR, 08 JKUR, 15 Ford Transit 350, 04 WJ 4.7, 17 Renegade, 99 Merc E430 S
Vehicle Showcase
2
I'm still on the factory 4.10 ratio with 315 KO2's and I've been happy enough not to change it, but a little more rpm in 6th would be nice, so I'd guess 4.56 would be the sweet spot.

What's the ballpark of the cost of the swap? Does Mopar offer 4.56 or other ratios with Dana rings and pinions?
 

Jeepjunkie

Well-Known Member
First Name
Eric
Joined
Dec 17, 2018
Messages
331
Reaction score
328
Location
Annapolis
Vehicle(s)
2019 JLU Sport
Vehicle Showcase
1
I'm still on the factory 4.10 ratio with 315 KO2's and I've been happy enough not to change it, but a little more rpm in 6th would be nice, so I'd guess 4.56 would be the sweet spot.

What's the ballpark of the cost of the swap? Does Mopar offer 4.56 or other ratios with Dana rings and pinions?
I paid $500 for labor and $550 for Yukon gears plus master overhaul kit, so < $1100 total (rear axle only, I had a new front axle). I’m sure you can get Dana gears in 4.56. The only way to get other gear ratios in a 3.6 or 2.0 gas engine, besides the 3.45 or 4.10 ratios, is a gear swap. I used a reputable independent shop rather than the dealer. The Indy shop has a better reputation and is cheaper.

I really think the 4.56 gears are awesome. It’s much more fun to drive. I have 285/70 17 tires now, and do 72 mph at 2500 revs and get about 19 mpg on the highway. I’ll go up to 285/75 17 next and I’m sure it will be perfect. Others have had good experiences with 4.88s too.
 
OP
willcasp

willcasp

Well-Known Member
First Name
William
Joined
Jun 23, 2019
Messages
280
Reaction score
153
Location
Bothell, WA
Vehicle(s)
2018 JLU Sport S
  • Thread starter
  • Thread Starter
  • #10
Quick update. I had the 4.56 gears installed.

SHOULD HAVE DONE THIS SOONER!

Completely transformed the Jeep. I can start in second gear when needed. All gears are usable. Went from averaging 16mpg to 21 mpg.
 

Jeepdude101

Well-Known Member
First Name
Isaac
Joined
Oct 28, 2019
Messages
414
Reaction score
1,728
Location
Arlington Texas
Vehicle(s)
18 JLUR black
Occupation
Construction field worker
Vehicle Showcase
1
Quick update. I had the 4.56 gears installed.

SHOULD HAVE DONE THIS SOONER!

Completely transformed the Jeep. I can start in second gear when needed. All gears are usable. Went from averaging 16mpg to 21 mpg.
Cool I will be going 315 70 17 in a month or two on my jlur 6speed I probably won’t regear for a while because I live in the Texas flatlands lol and I normally have cruise control set to 75mph people still zoom by going 85 to 90 Texans drive fast :)
 

Advertisement




Tazer JL - Z Automotive
 



Advertisement
Top