I'm in the process of buying a RIPP supercharger for my 07 auto jk. She's got Dana 30 in the front at Dana 44 in the rear (4.10). I was wondering if I have to regear to make some 37's run smoothly or will the supercharger have enough power so that I don't have to worry about it. I will be using it for DD and also trails, beach and maybe some rock crawling but nothing to crazy.

 

Have to? No.

But I bet that if you spend a few minutes searching you'll find half a dozen posts by Ripp telling people to regear for the new tire size before adding their s/c.



Here's one of them...

 

Regear then RIPP. Without the regear you won't see the true benefit of the SC. With my 37's and dana 44 am running 5.38's but we have a lot of hills/mountains our highways climb. Some people go with 5.13's and 37's with no issues.

 

yup regear .. then you will love the ripp even more

 

As many have said, we recommend that you re-gear before the install of the supercharger system. Tire size is directly correlated to the shift points of the transmission, resulting in speedometer being inaccurate and transmission being put through more stress than it needs to. If you are going to be running 37s on a 3.8L, a 5.13 should be fine

 

Re-gear.
Proper gears not only allow you to run bigger tires they will take stress of the entire driveline. If you throw a super charger on while running 37's on 4.10 you will be snapping driveshafts and stressing the transmission if you do any real wheeling.

 

Ive been searching the same thing. i would re gear with either 4.88 or 5.13.

 

with your 07 you want 5:38 with auto and 5:13 man trans running 37's. You won't be able to believe how good it crawls with the 5:38/37 set-up. Provided is a Rubi transfer case

 

We recommend regearing to 5.13:1 with Auto trans for the best balance of onroad and offroad driving. 5.38 if you do more wheeling than anything else.

RIPP