I know you can run a high pinion for the front diff. How can you gain some driveshaft clearance for the rear diff and driveshaft and diff?

 

cut your spring perches and rotate your housing, weld back on. Be careful of your pinion angle.

 

taller tires help too.

 

I am running 37s. Hopefully rotating will do the trick.

 

What is the best way to determine the correct pinion angle?

 

Angle finder tool.

 

the 4runner i got had a rotated rear end, and something kept vibrating on deceleration.

i ended up having to get a cv joint put in the front of the rear driveshaft, similar to how the front driveshaft is set up.

search the archives for info.

 

I had to switch to a CV rear shaft, clearance the "horse collar," and rotate pinion angle. Short wheelbase and dual cases. Used a piece of 10" pipe to arch where I clearanced the horse collar. Looks really good till you see my booger welds

Would be helpful if you gave specs and what the clearance problem is.

 

in order to "test run" the pinion angle, you can also buy angled shims to put between the leaf spring and the spring perch. I wouldn't use it is a permanent fix but its a good way to double check that you have chosen the right angle before you do all the work cutting and welding.

 

I have double transfer cases and a cv driveshaft. Three inch trail gear lift with five in h schackles.

 

I used string and an angle finder to figure out pinion angle. Then subtracted 2* to allow for spring wrap. Used angle finders to cut and weld on new spring perches.

To do it again I'd tack on spring perches then recheck angle of pinion with weight of truck on it.

The angle I had to rotate the rear pinion was more than was recommended with shims for a road driven vehicle. 70mph is about my top speed much over and I notice drive line vibrations depending on what's loaded in truck.

I also made re-enforcement plates to go in front and rear of spring perches as I'd seen post of were the commonly sold style will collapse.

Think 4crawler had a good link to a site that explained the different types of drive lines. Searched for you but couldn't locate.