scooby snacks

I'm running 4:88's with 3.6 and AT. Perfect for my use and I wouldn't go higher. If you live at a higher altitude then you may want to consider 5:13's but everyone I know that opted for 5:13's wished they went with 4:88's.

Good luck!

nthinuf

He ordered 5.13, or 5.38?

Your profile shows that you do not have a rubicon, which means you have a d30 front axle? Did he even find a set of 5.38's? (If he did, I would imagine that you are about to see a whole lot of comments telling you not to run them in a d30... )

What you might start with is verifying what year your mechanics JK is!! From what you are saying of his responses, he has a 3.8 auto, NOT the same 3.6 engine you have. Wanting 5.13/5.38 is much more common for 2007-2011. Newer years, 2012+, have more hp and better trans ratios, and if you open a few of the thousand previous 'what gears should I get' threads, you will see that 4.56/4.88 are much more common.

Mwsubway

no I have d44 front and rear, swapped them out already!

Mwsubway

he ordered 5.38!

Mwsubway

Well I went and spoke with him again yesterday and he said 5.35 would be fine and has put them in a few peoples jeeps and people loved them! So I guess I will see and wheel with it and share the results!!!!

Canvas

Be careful with the skinny pedal. My recommendation is to continue to run stock axle and drive shafts, so that your weakest link is not your ring and pinion. I ran 5.13's in my D30 with an Aussie locker and 35's and blew both front axle shafts with in 30 seconds on the same obstacle. I would also recommend carrying spare axle and drive shafts because it is not a matter of if but when and you do not want to be stuck out on the trail trying to get back to get the parts.

R/
Will

Mwsubway

Ok well that is one of questions I had asked also, but he said I should be fine! But again i'm a little skeptical about that also! Sounds like if I I'm satisfied with gears next will be the beef up stage!!!

Canvas

Of course he is going to say you are fine. When you blow out the ring and pinion you will be back to have them replaced and pay for more labor.

What gears are you going with?

Jeepstercanada

Gear chart to help you understand

Mike H.

I think either would be fine depending on priorities.
Personally, I went with 5.13's, and wish i had done 5.38's... 99% of the time the 5.13's are excellent... but that 1% when the rig is in some really precarious situation where lurching even the slightest amount risks body damage and/or rollover... I wish I had that extra bit of control a deeper gear would provide... and this is with the 4:1 ruby case. I will be going to 37's when my 35's wear out, and, will be going 5.38's at that time to offset the increased tire diameter.
I'm betting 90% of the people on these forums would opt to not go the places my rig has been, and 99.9% of Jeep owners likely fit that bill. I would agree for them 4.56's or 4.88's would be the cats meow. If you are going to go places where extra slow going is required to keep from crushing body panels and rolling the rig, go as deep as you dare... especially if you have the 2.72:1 case.
I think the chart above is excellent for the majority of owners and light to moderate trail use, if you are going to really wheel it (expect/accept body damage, use/utilize armor), the chart is not all that relevant.
My .02/opinion.