I will tell you what I did on this jeep and what I did on my last one running 37. I sleeved and gusseted both front axles. If you know a quality welder, do a truss instead if the sleeves. I don't know one and I'm not paying $200+ in labor. I put chromoly shafts front and rear on my 13, but ran stock shafts on my 12. I cut my stock flares on my 12, running PSC crushers on my 13. You will need to cut your pinch seams and I would highly recommend upper and lower rear control arms in the rear to move hour axle back a little.

My 12 did great for me and was running 37 on the cheap. My 13 is significantly better because I basically upgraded all the stock parts that are known to fail. Both ways worked great for me.

 

I honestly would not run 37's on a front d30. I know its expensive,, but do yourself a favor and save up for the pr 44! The gears and locker of your choice will come with that horible price tag. I would; however, run them on a beefed up rear 44. Either way,, good luck!

 

Agree with this. You're already pushing your luck running 35's on a D30. If you want to run 37's, at bear minimum swap in a Rubi front D44 and beef it up. If you plan to wheel it, more 'beef' is necessary.

You can definitely wheel it until you break it though. I was able to sell my D30 for $400 which will help you pay for a D44.

 

I agree with big dr. If you want 37's then you gotta pay to play. The ring and pinion are too small on the d30 for 37s. And you can't change that fact. And why would you want your weak link to be your R&P.

Save up and do it right. Why waste money by throwing cash at a d30. The prorock 44 comes out the crate ready for 37s. You can spend money beefing up stock parts, or you can buy a axle that's already built to rock. And yes you will need new ball joints, a high steer kit, etc if you wanna do it right the first time. IMO

 

I forgot to mention that if you think you will one day run 40in tires then skip the d44's and go straight to D60's

 

Thank you gentleman. I apologize for the vague question. I should have started off with best option for 37's for my front axle. As I have the height to fit them under me. Would you also recommend beefing up my rear 44 as well?

 

I'm going to follow this as well as I plan to go to 37s after my 35s wear out. I'm on 5" of long arm lift. I'm just curious how much cutting I need to do in the rear wheel wells. I haven't sleeved the D44 front either.

 

Doesn't all of these mods depend on what you actually do with your JK?

If you do rock crawling the bigger the better, but if you trail ride and a little mud like I do, would you really need all of this?

I have a stock Dana 30 right now with 35's and 4.56's and I don't think I will have a problem.

When I go to 37's I will truss it and don't think I will do anything else.

What is the worst? The Dana 30 fails? It is only worth $200-300 anyway, so I get a 44 and transfer the brakes.

What is wrong with this logic as I see it?

Most of my off road is forest trails at under 20 mph and flat in Florida.

 

You will be fine. Not much difference vs a stock d30/stock d44. Some 37s weigh as much as some 35s. It's all about how you wheel it. In my research, LOTS of guys have the d30 with 37s and going strong with lots of miles. And for better words " if its not broke, why fix it.."

 

I see nothing wrong with 37 on a d30 if you are prepared for something to break. It may not happen for a long time or ever for that matter, but the chances are definitely there. I don't think anyone is telling you that the minute you torque on the 37 that everything will fall apart. It is just more likely. Just sleeve or truss and add C gussets and you can do it. That will prevent a tube or C from bending. Axle shafts and R&P are still weak but if you replace the shafts, the R&P are the weak spot and that is a costly fix. Start saving for the what if, do the swap, and enjoy.