K5 Drive Driveshaft Grinding

[Kenneth Wilkins]

So I recently put a 6 inch lift on my 87' K5. When I got it back it had a terrible grinding noise coming from my tcase when I came off the gas around 40-45 mph. I rebuilt my rear driveshaft but with no luck. What I recently found out was the kit we put on they did not drop my tcase because it would "put stress up front because your rear would be lower than your front tcase" this didn't make much sense to me because they went on to say it would put stress on my radiator and pinion angle. I know people do tcase drops all the time and as far as I remember there are some 3/8" washers above my tcase on top of the frame that I can take out and use to drop my tcase to get rid of the vibration/ grinding. Any of this make sense to anyone? Thanks

 

[K85 Octane]

Lol, this feels so set up but I'll bite.

Drop the Tcase 1" using some square 1x1 tubing against the frame. DO NOT use the collars as "shims". Check the driveshaft angles with an angle finder. Search to see how.

 

[blazinzuk]

Did you shim your axles?

 

[Kenneth Wilkins]

I did not. I believe that was our next move but I wanted to post here first and hear what y'all had to say

 

[Blue85]

So I recently put a 6 inch lift on my 87' K5. When I got it back it...

Contradiction... sounds like somebody else put it on. You must always check (and likely correct) the driveline angles after changing the suspension height.

There's a slim chance that the angle is OK and you just need a U-joint, but 6" is pushing it withe an all-stock driveshaft. Did you get it lengthened at all? Is the rear lifted with springs, blocks or shackle flip?

 

[Kenneth Wilkins]

Contradiction... sounds like somebody else put it on. You must always check (and likely correct) the driveline angles after changing the suspension height.

There's a slim chance that the angle is OK and you just need a U-joint, but 6" is pushing it withe an all-stock driveshaft. Did you get it lengthened at all? Is the rear lifted with springs, blocks or shackle flip?

It's an all spring lift and we did lengthen the driveshaft. Sounds like it's just the angles at this point.

 

[80' 427]

First, put in new transfer case mounts, mine touched the crossmemeber after just a 2" lift. DO NOT drop the crossmember.