Getting ready to pull the trigger on new tires and really like the idea of 40's. What would be some upgrades that would be needed to run a 40" tire?? Ball joints, truss and gussets already done.

 

If your keeping your stock axles (which I'm assuming you are), id re-gear if you haven't yet, maybe add flat fenders and do some trimming. 1350 Driveshafts, hydro assist.

I mean you could prob throw 40s on and make due with what you have (dana 44s) but there are tons of upgrades that would make it more stout....

 

If you're a pavement princess then sleeves gussets bigger brakes longer driveshafts ring and pinions flat fenders and the power of positive thinking.

If you're actually going to wheel it on trails...Dana 60's and all of the above.

 

just slap those puppies on and call it a day! or do a little reasearch theres tons of threads on this. Hell my d44s barely hold up to 35s.

 

Ive been doing a lot of research in case i ever wanted to go down this road one day and im friendly with a guy who runs them and wheels them hard. ive driven his rig and asked a lot of questions. Besdies the obvious axle strength issues everyone is going to bring up and rightfully so the problem your going to run into right away is having the proper backspacing. Even if you planned on pounding the pavement with this rig you will need around 1.5 inches of backspacing to not rub the frame when turning. With that much backspacing your stock hub assemblys and ball joints will take a shit very quickly. Your better off doing it right and get some 60s front and rear (i would do full float if i had the means for the rear) that are much wider than stock. I cant recall the length of the minimum width needed but im sure someone else will chime in or just look up the specs for the prorock 60. Looks like you have plenty of lift but i would not run stock driveshafts either. Also say good bye to your stock drag link and tie rod those ends will not hold up and the stock tie rod itself will bend if you fart to close to it. Hydro assist would be nice to have if your going to be wheeling it. Hell im only running 37s and would kill to have it sometimes. I would also ensure you have the proper bump stoppage

 

Looking to pull up some big boy pants.... means saving for a motor. I'd add that little chunk of change to the build sheet.

 

I am sure there are people running 40's on a JK without changing almost everything.

But for me if I were going to build a JK on 40's to actually wheel (or even drive on the street for that matter) the only thing not replaced would be the body and frame.

Because I would not want to be repairing/replacing broken stock stuff all the time.

It would probably be cheaper or at least less hassle to just build a dedicated rock buggy and buy a trailer.