BulldogMJP

I'm just over 100000 miles and thinking about re-gearing from 4:10 to 5:13. I have a 2007 auto with 4"lift and 35's. Does re-gearing make alot of difference in performance. I find the ride OK with 4:10 and od off. Would going 5:13 will give me a big performance increase, or at least a noticeable one. I'd hate to shell out the cash and only get a slight gain.

Jk kris

Are you driving it everyday ? 5:13 is a a lot for a dd. you'll have a ton of pulling power out the hole but highway driving you'll be turning some serious rpms

tcdawg

It will make a nice difference. Is it going to blow you away and make you think you have a new motor, no. But it's a nice difference. Also helps your crawl ratio in 4 lo


5.13 for an auto on 35's is perfect. If you are breaking out the check book for gears you would not want to go any higher(numerically lower). I ran 5.38's with 35's for a year before I got my 37's, no problem.

You will be under 2500 rpm's at 70. Helps keep it from downshifting as much.

See if anyone near you has a similar rig with 5.13's and drive it. That will help you out in making your decision.

BulldogMJP

Yeah it's a DD. But I read 5:13 is best for an auto. Would it accelerate better and give me ability to use od again.

tcdawg

Yes. I don't ever turn OD off...5.38's and 37's.

tcdawg

This should help as well

BulldogMJP

Thx guys. 5:13 here I come.

DGriz

Is this the most current chart? Heck, if this is right, I should be running 5.13 with my 33" tires.

nthinuf

3.8 4door auto. I had 5.13's and 35's. Replaced the 5.13's with 5.38's when I swapped in a front d44. 5.38 is the better ratio for me.



Yep, these 07-11 autos are undergeared (underpowered) from the factory.

CerOf

That is the chart. If it is a true 33" tall tire when mounted, 5.13 would be fantastic. Most 33" tires when mounted are going to measure more like a 32.

Sent from some string and a few tin cans.