NoQuarter#121

I am planning a new JKU build.
I'm thinking I will upgrade from 37's to 40's on beadlocks this time.

I plan on heavy duty axle assemblies from one of the many current manufacturers.
So, in the interest of research what are your recommendations?

60's front and rear required? Recommended? Overkill?

Which brands have you liked or disliked?

Any brand I definitely want to stay away from?

TheDirtman

For 40's I would recommend at least dana 60's and do full float axles as the wight of the JKU is a bit much for semi float axles. Dynatrac is the most popular for the JK and Dana has come out with bolt on crate axles for the JK that have been well received. You will need new wheels and should look at a minimum of 68" in width and make sure to get the axle set up for your lift size. Look for your new wheels in a 3.5" bs or less with the 68" axle. Plan on hydraulic assist with the new axles and 40's

NoQuarter#121

Thanks for the info.

sea bass

UD-60's are a simple and cost effective route - unless you want to build your own junkyard axles?

SoK66

Listen to The Man. FWIW, this is a significant step so planning it out in detail is essential. I've been very impressed with Dana's UD60s. A friend swung a set under his '12, along with Raceline beads and Nitto TG 40s and said it was as close to plug and play as anything he'd ever done on his Jeep. However, he felt the extra weight and rolling resistance from the larger gears and tires sucked the life out of the 3.6L, so he did a Hemi conversion to complete the package. $$$$$$$$$$$!

caryt

Dynatrac's...either a PR or XD60 and a PR80 with 5.38's. Then your set no matter what you do in the future.

Canvas

There are so many axle choices out there from Dynatrac to Currie to Spicer to junkyard axles.

I have had a couple of friends do junkyard axles swaps and have run into issues with tone rings depending on the year of axles being used. Super Duty 05 and up seems to have the magic worked out for tone rings. On junk yard axles after all said and done you will be close to the money being spent for aftermarket axles. For myself since I am not a welder I have to pay for such service.

R/
Will

JKZinger

I am in the middle of this right now. Dynatrac ProRock 60s on order, Cooper 40s coming and new 8 lug slabs sitting in the garage. Already running coilovers so just gonna dial them up a little higher.

Take Dirtmans advice and get 3.5 backspacing on the wheels. Don't get anything less than 60s front and back for 40s.

JKZinger

This is a test post to see if it shows up in new posts as this app is having some issues.

Dynatrac

A new JK build is always fun, especially when you get to start clean slate and take all the previous experience you've had to make this new build even better than your previous Jeep.

Because of the weight and mass going with 40s adds to the ends of the axles, you definitely want to look at going with something like our ProRock 60 front and rear. You'll also need the extra braking power that comes with those heavy duty axles to get the jeep stopped.

There are a lot of options out there on this front. It makes things a lot easier to take the guesswork out as much as possible, in terms of both cost and the specs of what you'll need to support rolling on 40s. Give us a call at 714-421-4314, and one of our techs can go through everything you want to do with your new build, and work up a quote for ProRocks front and rear.