LJ With leaf springs and Cummins 4bt

Beowill · 03-13-2012, 07:40 PM

I thought this is the best place to be posting this question, as you guys know leaf springs the best.

I recently bought a wrecked LJ, and I am in the process of swapping a 4bt, NV4500 trans, and NP205 t case in.

Also, I'm going to be running Dana 60 front, and I'm not sure about the rear yet.

Tires are going to be 37x12.50 humvee tires on the humvee beadlockers.

I am eventually going to be running a 4 link/3 link, but I have neither the time or money now.

With all the extra weight, I need to know what leafs to run to easilly fit 37's with front tube fenders, and still have a lot of flex. I DO plan on doing a spring over axle conversion.

What springs, shackles, and whatever else should I run to have the optimal amount of articulation, road manners, and clearance for the jeep and the tires?

Any input is appreciated

**Louie4** · 03-13-2012, 07:44 PM

I would think XJ rear springs would work well for the rear. Try sending Kyle a pm, he did it with his TJ. Plus there were some other guys that posted in the thread that did it.

http://www.jeepforum.com/forum/f22/k...opper-1051428/

Beowill · 03-13-2012, 07:47 PM

And keep in mind that the drive train will weigh a good bit more than a stock 4.0. I think that the 4bt weighs something like 750 lbs dry, and the the nv4500 is 200 lbs, NP205 is 180 lbs, so 1125 lbs give or take

Sprungover · 03-14-2012, 07:59 AM

why not weld TJ mounts of the front 60 and run the coils?

**Louie4** · 03-14-2012, 08:02 AM

Quote:

Originally Posted by Beowill

And keep in mind that the drive train will weigh a good bit more than a stock 4.0. I think that the 4bt weighs something like 750 lbs dry, and the the nv4500 is 200 lbs, NP205 is 180 lbs, so 1125 lbs give or take

You could always run some waggy rear springs and add a leaf to it if needed. You may also want to post something in the Advanced Jeep Tech section as you may get more knowledge and experience on the subject.

http://www.jeepforum.com/forum/f369/

Sprungover · 03-14-2012, 08:04 AM

He needs to compare those weights to the stock weights. The 4.0 is a heavy pig.

**Louie4** · 03-14-2012, 08:06 AM

Quote:

Originally Posted by Sprungover

He needs to compare those weights to the stock weights. The 4.0 is a heavy pig.

The good thing about leafs is you can add/subtract leaves and make a bastard pack if need be to suit your needs. When you start mixing and matching power/drivetrains there is a lot of trial and error. The Wagoneer springs I mentioned already hold up one of those beast.