Anyone running this setup? How is the gas mileage and rpm at highway speed? Power?

 

standard or auto trans?

 

I will be running 31's with 4.10s soon. Should get it close to stock-ish final drive. I do not remember the site address, but you should be able to google a drive ratio calculator. And find the differences.

 

I've always wanted to run 4.10's with my 31's. Im curious to hear how it works from people that actually have that setup

 

4:10 and 3:55 are great all around with 31's but with a auto transmission much better with 33's. Smoother shifts and feels much more powerfull.

 

This will be your best friend. And yes, 4.10's would be perfect.

 

Sounds good. I'm still debating whether to regear the jeep or just sell it and buy something diesel where I can have power and good fuel economy.

 

I have 4.10s and 31" ATs. First gear is useless on the street.

33s are the diameter that bring speedo back to stock.

 

That chart is for 1.1 gear ratio doing 65 mph. You will need to multiply the 2896 rpm by either .75 for the auto, or .79 for the manual transmission to get the correct rpm at 65 mph.
Which would give you 2172 rpm with the automatic at 65 mph, or 2288 rpm with the manual at 65 mph.

 

Theres Different charts for the Auto vs Standard to I believe...

 

http://www.manoian.net/jeep/gear_ratio_calculator.html

try this link...this is by far the best calculator i have used

edit: although i just realized it does not have an aw4 on the list

but, choosing ax15 instead should give you a close enough answer if you're just looking for the highway speed/rpm

 

but, 4:10's with 31's will be great with an AW4

 

I'm running 31" BFG MTs, 4.10s and an auto. Love it! Can lay tire from a stop (not that i'm one of those people), accelerating on the highway is quick and easy and towing is much nicer also. Fuel economy didn't change noticeably (fuel economy is controlled much more by weight and aerodynamics anyway). Overall, it's great and i'll be keeping the 4.10s when i go up to 33s.

 

This sounds promising. I'm running 31s with the aw4 and stock gears and its just not cutting it. Third on the highway revs too high but in overdrive I have to downshift every hill. Not to mention i can stuff it and the passenger probably couldn't tell unless i told them.

 

have the 4.10 and 31's here and can't complain. Couldn't get over 60 on looooong hills but runs 75 no problem and has plenty of beef for the offroad. I did about 260 miles on a tank, with loooong hills and loaded down. Mines an auto, tacking about 3k at 75-80, an speedo is dead on.

and by the way, when it's 100 degrees and you hit one of these looooong hills, it's best to turn off the a/c. dumba**