i got an 85 toyota and read through the 63 inch spring swap FAQ at least a dozen times. i got some springs, new u bolts and made up some hangers for the front. got her all together and have lots of rear driveshaft vibration. do i just need some of those shims under the spring to correct u joint angle or is there some other way to fix this problem? also it looks like my rear d shaft is pulled at least 4 inches out at the slip joint. any help would be much appreciated!

well if you moved the rear end backwards chances are that you need to get the rear driveshaft made longer...

Get an angle finder and check t case output shaft angle, and pinion angle.

Both should be matched (-3* and +3* for example) or as close as possible for minimum driveline vibes.

And once you figure that out, you can make an adjustment to pinion angle with a steel machined shim. Diy4x.com has a bunch of steel shims to choose from.

Get your driveshaft lenthened. I'll bet money that your driveshaft comes apart on your next wheeling trip if you don't.

I'm not a expert but i have heard that when you swap to the chevy springs you really need to add a good traction bar also. I agree that it is probably a short drive shaft giving you problems, but i would bet that a tract bar would need to be done in the near future..

Well, right or wrong, I haven't installed an anti-wrap bar yet, and have been able to get away with it (fingers crossed)

The only time I have noticed wrap problems is loosing traction on dry pavment.

Well, right or wrong, I haven't installed an anti-wrap bar yet, and have been able to get away with it (fingers crossed)

The only time I have noticed wrap problems is loosing traction on dry pavment.

Yeah, i was just wondering if when under accleration it would pull the shaft out even further? or with too much axle wrap it would make the drive shaft bind worse..

i got an 85 toyota and read through the 63 inch spring swap FAQ at least a dozen times. i got some springs, new u bolts and made up some hangers for the front. got her all together and have lots of rear driveshaft vibration. do i just need some of those shims under the spring to correct u joint angle or is there some other way to fix this problem? also it looks like my rear d shaft is pulled at least 4 inches out at the slip joint. any help would be much appreciated!

its the driveshaft.. it needs to be lengthened or the axle needs to be moved forward.

Get an angle finder and check t case output shaft angle, and pinion angle.

Both should be matched (-3* and +3* for example) or as close as possible for minimum driveline vibes.

And once you figure that out, you can make an adjustment to pinion angle with a steel machined shim. Diy4x.com has a bunch of steel shims to choose from.

Get your driveshaft lenthened. I'll bet money that your driveshaft comes apart on your next wheeling trip if you don't.

X2 good advise :smokin:

Add a cv to the shaft and shorten to proper length, The cv will be needed in the end anyway and being pulled that far out of the spline thats what is causing the vibration.

Get an angle finder and check t case output shaft angle, and pinion angle.

Both should be matched (-3* and +3* for example) or as close as possible for minimum driveline vibes.

And once you figure that out, you can make an adjustment to pinion angle with a steel machined shim. Diy4x.com has a bunch of steel shims to choose from.

Get your driveshaft lenthened. I'll bet money that your driveshaft comes apart on your next wheeling trip if you don't.


thanks for the info!

With shackles in the rear of the spring, during articulation the drive shaft will compress not pull apart. Travel toward the t case. fyi

With shackles in the rear of the spring under articlation the drive shaft will compress not pull apart. Travel toward the t case. fyi
Do you mean acceleration?

oops fixed :laughing: