6" lift 89 blazer HELP!

[zeeker]

Need some tips for getting rid of vibration,
New Pro-Comp 6" lift, new leafs front and rear. New driveshafts, front and rear. Low speed vibration from rear shaft.
Any successful stories on removing it would be great?
89 Blazer full size.

Thanks......Dale.

 

[mtnman210]

you're using 6in procomps get used to the vibes and ruff ride just messing with ya those are the same springs I'm running. What's your pinion angle like? and I'm not too familiar with that year but if it's a chain driven transfer case that could also be the source of the vibration. I know I get a really bad vibe from that when coasting. Someone please chime in and correct me if I'm wrong about the transfer case

 

[zeeker]

Pinion angles are 2 degrees out. I had a 4 inch lift before and it ran as smooth as a Cadillac. I was thinking of shiming the rear, but not sure.

 

[mtnman210]

I had to use shims with mine, without them I was way off. I don't know what degree they are but I could snap some pictures of them tomorrow if you want to have a visual.

 

[zeeker]

RE: pics

That would be great.. Thanks. How is the ride after the shims?

use this e-mail [email protected]

Thanks.....Dale.

 

[muddybuddy]

put a 5* shim in there, will make a big difference.

 

[mtnman210]

Rides fine. It's not the smoothest in the world but let's face it's not a caddy. I get a little bit of wheel hop when climbing hills but I'm sure thats more from the blocks than the shims.

 

[zeeker]

Thanks for the pic. I don't have blocks in mine, I'm using the 6" lift leafs from pro-comp.
I think the rear is about an inch lower than the front, might be an illusion because of the way the fender wells are on the blazer.

 

[mtnman210]

I think the rear is about an inch lower than the front, might be an illusion because of the way the fender wells are on the blazer.

thats what the blocks are for. I've got 6in springs front and rear but I didn't want it sitting unlevel so I got blocks too.

 

[Stephen]

You may have to go to a CV jointed driveshaft, we usually start recommending a CV shaft at the 4" lift range, chances are slim that you'll get it to run smooth with a 6" lift. There's a bit of leeway with different gear ratios though, so if you don't re-gear, you'll have a better chance to make it work without a CV. If you go with a CV joint, get with us for a SYE kit, it really does help with the angles.

To start with now, drop the T-case some and match the angles up as close as you can.

 

[redneckdude]

im prob one of the few whos gone with 7" and got it almost perfect...slight vibes off the line but thats all. Ive still got my stock length shaft too but soon after i get my rear suspension all figured out im gettin the sye, e-brake and shaft from jesse at HAD...driveline vibes can be 98% cured with a 6-7" lift but in the end it is better to jsut go with a cv shaft when money permits.

 

[Stephen]

What gears and tires are you running? Mine worked fine with a 3" lift and 33's with the 3.73 gears but when I went to 4.56's it was never right again. the faster driveshaft speed seemed to be the key to the problem. And bigger driveline joints may not have helped, I went to 1350's when I did the gear/axle swap.

 

[redneckdude]

i was running 3.08s and 33s with stock s44 joints. i know it worked for me, but i still would have rather had a SYE and the works...but i could cruise at 80 down the highway all day long with no problems.

 

[Stephen]

That would explain why your driveline is so smooth, it's barely spinning! Run that sucker 1.5 times faster (like with 4.56's) and I think you'll find a different scenario.
This is a good data point to keep in mind though, in a lot of cases, you'll be fine till you do a gear swap. Also keep that extra cost of the driveshaft in mind when you do a gearswap so it doesn't surprise you.

My sub with roughly 4" of lift and a SYE 241 has to be lined up just right to run smooth with 1350's and 4.56 gears on 35's.