M.I.T in El Cajon

I used them for all my work when I lived in SD

 

I have a 2.5 lift and flat fenders. It's not the engine rpms..its the drive shaft. It's spinning faster with those deep gears and spinning super fast amplified any vibes. My ds are stock but I should replace my front sometime soon. Torn boot from the transmission pan.

 

Mispost

 

Thanks...I've gotten "MIT" from multiple people...it was a great sign until I called and got the highest quote of any place I called. They were SUPER friendly and thorough taking my info for the quote. Very knowledgeable etc etc...I just can't drop that much more coin over the going price. Offroad Evolution's $999 materials and labor + return visit after 500 miles for diff service is pretty much unbeatable. It's just going all the way back up there for that Diff service which is a killer from San Diego

 

I manage a high performance shop in the Seattle area and I require my customers come back for fluid service and inspection after 500 miles. It's the only way to unquestionably warranty a potential issue. I understand it will take a little driving to do the 500 mile service but if you have an issue you'll appreciate not having to pay another $1000 in the long run.

 

Been running Yukon 5.38s with 37s on my 09 JKUR for about the last 30000 miles, no issues whatsoever. If you're sticking with 35s, 5.13 for sure. Fwiw, my first regear was to 4.88s, don't even think about it if you have a 3.8.

 

Great to hear the 5.38 are holding up for you. That's what I'm going with next week from Rebel Offroad. Not positive my next set of tires will be 37s but if not I'll likely do 35" Toyo Mud Terrains, which are tall and heavy.

 

Why are we even talking about lift size when it comes to gear decisions? It dosent matter if you have a 12" lift or you slam it with air bags. The 2 main factors you should be paying attention to for on road driving is tire size and manual or auto trans. If you have a 3.8 engine and an auto you should pair 5:13 with 35" tires for the best all around performance. Any more will start to give you too many rpm at highway speed (70mph) and any less will just be a turd. Also the 5:38 ratio is pretty much the max recommend for the D30 axles that are in the Sahara and x models. It's not a problem for the D44 axles which the Rubicon has on both ends.

I currently have 33" toyo MT's with 4:88 gears. It's geared right but I'm going to 35" and am regearing to 5:13. The 4:88's will work but you are right about them being ridiculously heavy. They need all the help they can get.

 

X2 you took the words out of my mouth. I had the same Experiance.

 

Right disconnect lift from this discussion it has nothing to do with gear ratio.

Howeever 5:13 with 3.8/auto/35". Is too high IMO. I had it and it was just too high. 4:88 with the engine Trans tire combo was perfect.

Now, if you think might go to 37's then 5:13 or 5:38 is best.

One other thing to consider is weight of tire and wheels. I know when I upgraded to 37" on 5:13. I switched from steel to alloy wheels. The weight of my 37 on allow was the same as my 35 on steel. She performed awesome/just right! Then I put the steel back on and wow performance really dropped! So... Rotational mass is a factor also. I'm either switching back to alloy or just going all in with method 105 beadlocks. Actually a touch lighter than my steel wheels.