I have a 2007 jk about to run 5:13 gears. Can you run 37inch tires with those gears?

 

5:13 is the proper ratio for 37s

 

I have a rubicon express 2.5 lift with a 1 inch teraflex front spacer. I'm running 35 but want 37 can I do that with my lift or do I have to lift it more?

 

Theoretically with flat fenders u can run 37s with no lift. Realistically if u plan on wheeling and getting good flex you should have a 4" suspension lift. You should be fine with your lift if u have flatties, u might have to do a little trimming on the pinch seem.

 

Yes, you'll be okay, but you could go 5.38 as well.

 

More information would get you better answers. 2dr or 4dr, auto or manual, mostly in town or mostly high speed freeway, towing, axles (D30/D35/D44), added weight/armor, stock flares or flats, disconnecting, fire roads or flexing in the rocks, whatever else may be relavent.

If you haven't found the FAQ's yet, you might give them a quick read. (stickied right at the top of this modified area.)