shimming the rear end.....

[mike4089]

my rear end is in the shop getting re geared and when i get it back i want to put a bigger shim under it...the one i got with the lift springs is just to small and the pinion angle is horrible....however if i put a bigger shim on the spring im afraid that the pin that the perches sit on will be to short.....what am i suppossed to do....i will eventually down the road get a cv driveshaft but i need a solution to hold me over until then.....

[CJim7]

Does it vibrate going down the road?
Ideally, on a single cardan driveshaft, the pinion angle should be the same angle as the output angle. Shimming the rear axle changes that geometry and can create just as much vibration as a driveline with to steep of an angle.
You're better off dropping the transfercase a bit or biting the bullet and going with a double cardan driveline (CV)

[mike4089]

well it never id vibrate with the straight 6 but once i put the 360 in it i ripped right through a u joint becuase it vibrated so bad....when u drop the transfer case does that change the whole angle that the motor and transmission sit at because they are all connected....and where can i get the stuff to drop the transfer case

[CJim7]

The swap "shouldnt" change anything....but you never know. When i swapped in my 401, replaceing the 258, there wasnt any change to the driveline angle...but every swap somehow turns out different.
Did you have to relocate the positioning of the tranny/xfercase on the crossmember? did you use stock V8 frame and motor mount brackets?
It's more then possible the swap created a different drivetrain angle. You can self-diagnose it by checking the output angle and compareing it with the pinion angle. You want them as parrallel as possible. Dropping the xfercase will lower the angle of the output shaft....because it's pivoting on the motor mounts.

One last question, with the onset of the 360 swap, has your right foot become heavier? :?:
The 360 has ample power to force axlewrap on the rear axle. Obviously, when the pumpkin moves, the pinion angle changes. I've seen axlewrap trash ujoints and driveline yokes. That's something to also consider :-|

[dwg86]

You could get a grade 8 bolt and install it in the leaf springs and use 2 nuts. The double nuts should be long enough to go through the shim and axle pearch.

[mike4089]

i just didnt know if i took the pin out if it would affect the spring packs....i see that the pin is just held in with a nut on the bottom....also the pinion angle is a little bit more extreme then the angle of the drive shaft coming off the transfer case...maybe ill try the grade 8 bolt....anyone have any good reasons not to try that....

[tufcj]

Use a C-clamp to hold the spring pack together when you remove the centering pin, there could be tension on the leaves, especially if they're still attached to the Jeep. You can go to a 4x4 or spring shop and pick up some centering pins. All they need to know is the diameter, which will be either 5/16 or 3/8". They're threaded all the way to the head. Run a grade 8 nut up to the head, then grind the corners off if you need additional height for shims.

Bob
tufcj

[dwg86]

That is what I did to mine. Just clamp the springs together before you remove the stock bolt. It will make things a lot easier when going together. I used fine thread bolts.

[Texas Tigger]

Yea... just dont pull the dumb #ss move I did. I must have been having one of those blonde moment when i was working on my spring pack. I was putting in some new centering pins and the spring kinda bound up when i was tighten them up, so I waked it with a hammer (no big deal) unless you had just sprayed WD40 on the old one to get it loose. (Oh MY EYES... got a face full) :eeeeek: looked like a fool crawling across the yard felling for the water hose. HEY but the springs turned out great!

[mike4089]

well i got an allen head bolt grade 8 and it worked out great.....thanks for all the advice