Funny vibration/noise after eliminating transfer case drop

[k5floyd]

Just thought id share my experience on my k5. i used 4" tc springs up front and ord shackle flip in the rear.

when i first installed the lift i had some vibrations on my rear drive line, so dropped the tcase an inch and that helped some. then i got shims, i believe 6 degrees, put them in and raised the transfer case back up. that got my slip yoke and pinion within a degree or two and my driveline vibration went away. but the combination of raising the tcase and pointing the pinion down some pulled the slip yoke out enough that it vibrates like hell on the tcase output shaft when i let off the throttle. this vibration is different than the driveline vibe in that its not felt nearly as much as you can hear it, its loud and a much higher frequency. im pretty sure just lengthening my drivelines will solve this.

 

[dieselndixie]

what rear axle do you have?

I have already lengthened my driveshaft, I am going to try a tcase drop. I am actually thinking I need to REMOVE the shims that came with my rear lift springs because my tcase angle is 8* and my pinion angle is 10*. I am convinced that is the cause of my vibes and noise. I agree though, I HEAR the vibration noise more then I feel it. And its really only when i let off the gas.

 

[clandr1]

Wow, this is an oldie!

My vibrations were minimized after taking the truck back to 4WP and having them do a combination of shims and TC drop, but I've decided that the permanent fix is to have a double cardan/CV style rear driveshaft made to fit the truck. Then I'll most likely be able to remove the shims AND the TC drop.

 

[dieselndixie]

An oldie but goodie...

Thx. I ordered a tcase drop and may try removing the shims on mine to get the angles to match. Right now my tcase is down 8*. And my pinion is up 10*. My shims point my pinion up. On my 14bff

 

[K85 Octane]

Diesel: If you draw a straight line from axle yoke to T-case....is the axle yoke going on top of the T-case or below? Confused by all this degree stuff, I haven't had to do much other than front steering caster.