4.56 or 4.88 gears?

CHAWK

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Mississippi
I have a Tj wrangler rubicon 4.0 automatic I am running 33” tires and I am about to re gear due to some issues I am having. The shop that is doing the work is telling me to go with 4:88s. It is a daily driver. Would I be better off with the 4:56s
 
Since you have a Rubicon you have the 4-speed automatic. So X2 to the above advice to go 5.13 which will provide optimal highway rpms in addition to great offroad performance.

And don't listen to some shop yahoo when/if they try to talk you out of 5.13. The 5.13 recommendation is because of your transmission's ultra-steep .69 Overdrive ratio that drops the engine rpms too low when cruising on the highway.
 
Thanks for the feedback Jerry. So the 5:13s will not be too low on the highway s and interstate at higher speeds right?
 
Thanks for the feedback Jerry. So the 5:13s will not be too low on the highway s and interstate at higher speeds right?
Nope. As above 5.13 rpms will be ideal for highway speeds. I'm running 5.38 with 35's with the same transmission and my highway rpms at 70 are ok but I actually wish they were just a little higher.

I almost forgot to mention my mpg went up from <12 mpg to 14.6 mpg after regearing from 4.88 to 5.38. The engine was operating more efficiently and not lugging at the slightly higher rpms.
 
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Jerry is spot on- you will enjoy more power with less throttle opening, contend with traffic better and get better mileage- it is one of the few things in life that sounds to good to be true that really is true.
 
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Going from 4:10 to 4:56 not worth cost. 4:88 is ideal though for a dana44 in itself.
 
Thanks guys for all the valuable info. Looks like I will be rolling with the 5:13s soon. Will let y’all know how they are.
Go with the thick version of the 5.13 gears so they will fit your Rubicon locker cases. The below is from my install.

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Nope. As above 5.13 rpms will be ideal for highway speeds. I'm running 5.38 with 35's with the same transmission and my highway rpms at 70 are ok but I actually wish they were just a little higher.

I almost forgot to mention my mpg went up from <12 mpg to 14.6 mpg after regearing from 4.88 to 5.38. The engine was operating more efficiently and not lugging at the slightly higher rpms.
Not trying to hijack this thread but I have a question.

I have an 06 JL Rubi with 35s and I'm about to do a regear. You said you have 5.38s with your 35s but wish it was different. What do you recommend then for highway speeds and 35's?
 
Not trying to hijack this thread but I have a question.

I have an 06 JL Rubi with 35s and I'm about to do a regear. You said you have 5.38s with your 35s but wish it was different. What do you recommend then for highway speeds and 35's?
5.38 is as as low of a ratio as can be installed into our Rubicon axles with Rubicon lockers so that's my recommendation for our TJ Rubicon axles with an automatic transmission. If I had big aftermarket axles like from Rockjock or Dyna I'd go with a lower ratio like 5.89 but that's not possible for a TJ Rubicon Dana 44.
 
5.38 is as as low of a ratio as can be installed into our Rubicon axles with Rubicon lockers so that's my recommendation for our TJ Rubicon axles with an automatic transmission. If I had big aftermarket axles like from Rockjock or Dyna I'd go with a lower ratio like 5.89 but that's not possible for a TJ Rubicon Dana 44.
Thanks Jerry
 
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5.38 is as as low of a ratio as can be installed into our Rubicon axles with Rubicon lockers so that's my recommendation for our TJ Rubicon axles with an automatic transmission. If I had big aftermarket axles like from Rockjock or Dyna I'd go with a lower ratio like 5.89 but that's not possible for a TJ Rubicon Dana 44.
If you wanted to change lockers you could go 5.89. Expensive though.
 
5.38 is as as low of a ratio as can be installed into our Rubicon axles with Rubicon lockers so that's my recommendation for our TJ Rubicon axles with an automatic transmission. If I had big aftermarket axles like from Rockjock or Dyna I'd go with a lower ratio like 5.89 but that's not possible for a TJ Rubicon Dana 44.
Do you recall off the top of your head which speedo gear you ended up using?