wat does a spacer do?

 

stick with the 37's, anything bigger you'll need new axles.

 

Amen! I can blow up a D-30 wearing 35's in my driveway...

 

maybe you should just start out with 35s and and kinda build your way up to 37's
first start out with lift and tires
later gear it
guesset it and new axel shafts
tire carrier bumper
and then by that time you will be ready for 37s

 

screw it, go to straight to a long arm and 37's!

 

get a second job and read all the info over at http://project-jk.com/

 

what axles would i need to buy to run 40?

pics would be nice

 

If you are going to run 40's you should upgrade your axles to D-60's. You MIGHT get away with improving your rear 44 significantly and then buying a 44 for the front, improving it significantly and being VERY easy on the gas. Best bet and cheapest in the long run if you want to put those 40's to good use is to save your $$ and get 60's.

 

would 40s even be good for road tires with all the right mods??

 

I don't see why not short of maybe snow and ice on pavement, breaking thru while spinning and contacting the pavement causing damage. With 40's even only driving on pavement you will want to sleeve the axle and add c gussets. Heavy buggers with a lot of force hanging off the end of your axle. My intention is to max out the build on my current JK and use it for wheeling then buy another say Rubi for the bells and whistles, build it to look sweet and use it for a daily driver. They both would be wearing 40's but I wouldn't worry about the mall crawler on D-44's.