I have a 7-9 cognito lift in my truck. The rear is lifted with add-a-leafs and a 5"ish block. The blocks are angled blocks to correct the pinion angle. Even with the blocks, my pinion points down pretty far. I have a pretty good vibration that starts at 69 mph and is gone by 72 mph. I was just curious if anybody else had any similar problems with rear driveline angles before I started messing with it. I am also thinking about a total replacement rear spring to use without the blocks and I was looking for options to go that way also. Thanks in advance..........

incorrect pinion angle can lead to vibrations and premature wearing out of the u-joints, and bearings in the rear end. i don't know what the correct angle should be and maybe someone will chime in with more knowledge. have you checked the tires for correct balance?

Yeah... I don't have many miles on these tires, so I think they are balanced o.k. I am going to put an angle finder on the pinion and see how far off it is from the transfer case slip yoke angle. I know they should match. I am wanting some rear springs pretty bad, these ride like poo......

Swap out the rear block with a 5" straight block. This is the issue. Try this out.

I have a 7-9 cognito lift in my truck. The rear is lifted with add-a-leafs and a 5"ish block. The blocks are angled blocks to correct the pinion angle. Even with the blocks, my pinion points down pretty far. I have a pretty good vibration that starts at 69 mph and is gone by 72 mph. I was just curious if anybody else had any similar problems with rear driveline angles before I started messing with it. I am also thinking about a total replacement rear spring to use without the blocks and I was looking for options to go that way also. Thanks in advance..........

Do you happen to have any pics? If anything the pinion should be up due to the angled block. The short side should be facing forward. If you change to a "Flat" block the poinion will come down even more so I might think either the block is installed in the wrong direction?

Also this truck is a 1-piece rear drive line correct? Should be but just making sure.

I don't think I have any pics of the rear blocks, but they are installed the "right" way. It just does not look like they are angled enough to get the pinion up. I still have not checked the angle, but will try to do that and get some pics. Oh yeah, it is the one piece aluminum shaft also Nick...........

The tapered rear blocks, if installed correctly, should have adequate raise to the pinion to be ok. I know you do not have a ton of miles on the tires, but I highly recommend having the balancing checked again! 8 lug aftermarket wheels can be tough to get truly balanced. It takes a little extra time most of the times compared to other wheels. But if you can get some pics of the pinion angle at the axle end of the driveshaft and also a pic of the angle of the ujoint at the front of the driveshaft coming out of the transfer case.

check you tire pressure.. when I got the truck back from the shop, couple days later, I noticed at above 50mph i had a bad vibration, I had 8" deaver springs with a 6degree shim..I was freakin out, all this moiney spent and i got this..Ended up being low tire pressure..dumbass me...

the spot where i got my rims at gave me free mount and balance, but unfortunately didnt put in the correct tire pressure, it was by 15-20lbs..

I have the same exact problem you desrcibed other than mine has the 2 piece driveshaft and 6 inch pro comp lift. I messed around with tires and balance yada yada. I moved the driveshaft up and down. I measured the pinion angle and transfer case angle with an angle degree finder. They are both within less than 1 degree of each other. I am told by Pro comp tech to go to a straight cut block in the rear and see if vibration goes away. Pro comp doesnt offer a straight cut block so he refered me to buy the block from superlift. The part # for the 4inch block is 048 and the 5inch block is 058. I am up in smoke with this as well. You have described to a T the speeds that I am having trouble with. Hope we get this one resolved before something bad happens to the rear end!

I had basically the same setup as you, and flat blocks were within specs for a one piece driveshaft.

Grab yourself an angle finder, and read this page. It's a bit more than just matching the angles.

http://www.4x4wire.com/toyota/tech/driveline/

I switched to 7" Betts Springs and couldn't be happier.

Have you tried rotating ur tires to to be sure thats not the problem big tires are hard to balance and are sometimes out of round. New means nothing

Hello all I installed the 4" blocks with no angle to them and vibration is history. I tried everything from tire and wheel balancing to moving driveline up and down. Moving the driveline just changed the speeds where the vibration was happening. I finally got this fixed by installing the blocks superlift make part #02-048. Hope this helps.

Seems you solved your problem, I had the same issue at the same speeds and have been chasing that vibration for months. It was also a pinion angle problem. angled blocks had too much angle and flat blocks not enough. I used the angled blocks with a 2.5 degree spacer to take some angle out, Problem fixed!

Seems you solved your problem, I had the same issue at the same speeds and have been chasing that vibration for months. It was also a pinion angle problem. angled blocks had too much angle and flat blocks not enough. I used the angled blocks with a 2.5 degree spacer to take some angle out, Problem fixed!

Dave, where did you get the spacer from? Thanks...

I got them from a local spring and suspension shop, I also had to buy some new u-bolts cause I couldn't re-use my old ones. you have to loosen your u-bolts about an inch to get the shims between your axle and spring perch. There is a dowel on the blocks that locate your axle housing relative to your springs. Make sure the dowel is long enough to go through the shim and still go into the axle housing. The shim I used was just thin enough to allow this, if I had to go with more angle I would have had to figure out a way to locate the axle.