Hellbound13

What will upgrading to 4.10 gears do for me? More torque? Will it lower my gas mileage?

I am running stock on a 2 door X, automatic with BFG mudterrains.

tgrt

What size tires? It also will depend on how you drive. Mileage on my JK going from 4.10s to 5.13s with 35"s improved slightly -- probably because I don't have to mash the pedal as much to get going.

Hellbound13

I currently have 3:21 gears and the tire size are the standard ones that come on the rubicon. (they were taken off a rubi) so I think those are 32 or 33?

I am tired of my OD locking up at 1500 RPMs and having to mash it to get it out, so I am wondering if the gear upgrade will lead to better shifting. Should I go higher than 4:10?

Also my dealer said they can do this, are the MOPAR gears worth it?

britjk

" Also my dealer said they can do this, are the MOPAR gears worth it? "

Well they put them in as OEM gears on the 2007 towing package and the Rubicon. I have them on mine and I'm running 34's and they work fine.

Jeepin Dad

If you have an automatic you have 3.73's not 3.21's so it won't be that big of a jump. You will get a little better acceleration and your gas milage will probably drop a little

Hellbound13

Just looked at my window sticker. Says I have 3:21.

Jeepin Dad

3.21's may be listed under standard equipment, look your options because '08 autos came with the 3.73 gears.

tgrt

Your mileage may actually improve slightly -- again depending on how you drive. The 4.10s with 32s are not exactly peppy, but you'll feel the difference even from 3.73.

I have my spare 4.10s. Send me a PM if you're interested.

Hellbound13

Ok so does MOPAR make anything higher than 4.10? Cause I don't want to void my warranty with aftermarket gears.

Basically I have been having the problem where the OD kicks in at 1500 RPMs and requires wide open throttle to kick it out of this gear. For some reason if I hit the OD button on the highway it kicks it right out, but if I hit it driving locally it doesn't and requires me to put the pedal to the floor.

After exhausting every possibility the dealer had me ride with their master tech. He said there really is not much he can do and that this is the nature of the lock up TC and the four speed 42RLE tranny. He has reset the software but after it learns my driving habits it always comes back after 500 miles or so.

He then suggested regearing might help and that might make the OD lock up at no such a low RPM but couldn't promise it would help for sure. Thats why I am wondering about regearing. I asked him about 5:10 gears and he said that would be too much for the stock tires. So now Im trying to figure out if it is worth regearing in order to get better day to day drivability on this thing..

Jeepin Dad

It sounds like you might benefit from a programer that will let you reprogram the transmission shift points.

http://www.quadratec.com/products/17614_5001.htm