I think I want to regear my XJ. I have 30in tires now but I will be buying 31's next. I have no idea what gear size I have now but I've been thinking about going to a 4.10. My XJ is my DD and I'm averaging about 16 MPG. I drive pretty close to 50/50 Hwy/City. What do you think?

 

they are expensive haha. If you have an auto more than likely you have 3.55s if its manual then more than likely its 3.07s. If you have manual i would just swap out axles with an auto and be done, but i am guessing here that you have auto. 4.10s might be a little high for 31s but i am not 100% sure on that, but you probably wont want to do them again when you go up to 32s so its up to you. Plus im sure someone has a chart around here haha.

 

if you have 355 gears already then youll be okay with 31s, if you have the cash to do it then id go with 410s to keep the stock ratio.

 

I do have an auto and I have LS. I can't explain why I feel I need one but it feels like a lower gear would be better.

 

I was looking at Rusty offroad and they have the gear for about $350 for both.

 

lower gears will give you more power, but wont freeway as well.

 

Don't waste your money re gearing for 31s. If you ever plan on going bigger than 31 then just go to 4,56 and be done with it. Paying money to re gear for 31s is pointless

 

X2.

 

Its not the price of the gears that is the problem, its the install. You would still need an install kit for each and then someone to do it. I was quoted about 1200 for front and rear and that included everything, him buyin the parts and oil and install and that is a good deal. Course he isnt a shop so if you go to a shop then it would be even more

 

Not to mention a 3.73+ carrier as well

 

Guy's, thanks for the advise. I'm not going to wast my money on gears, I'll use it on something else.

 

4.10 gears is pretty low on 31's. 3.73 would get it back to about stock. Just for future reference.

 

if yo have a 5 speed.... swapping an axle from an auto with 3.73's will be much better

 

yea except autos have 3.55s

 

Some of the older auto's with the tow package had 3.73's. But they didn't have the 29 spline 8.25 in the back. Some of the older 4 cylinders even had 4.10's in them.

on a manual to get back to a stock equivilent you'd want 3.55's for 31's, 3.73 for 32's, 3.96 for 33's, 4.10 for 35's, etc....

on an automatic you'd want 3.73 for 31's, 3.96 for 32's, 4.10 for 33's, 4.56 for 35's, etc...

Never hurts to go the next step lower for a little more umph