Vibrations!!!!

[bigbadchev72]

I have a vibration that is driving me nuts! I am running a 72 blazer 44/60 axles 4.56 gears 350/465/205 8" suspension lift 35x15x16 boggers.

Here is the deal. Ever since I put this thing together it has had a bad vibration from 15miles an hour and below coming to a stop especially, it rattles the whole truck pretty bad. I tore my 84' shortbox apart to build the blazer, I had the same vibes but it was nowhere near this bad, just a little vibration coming to a stop, nothing compared to the blazer.

I chalked all this up to bad driveline angles, I just bought a High angle driveline cv shaft and rotated the axle perches today, the pinion is 1* below the driveline angle to compensate for axle wrap. It helped a little but nothing to what I hoped.

I was at my brothers and was having him pop the clutch to check axlewrap There is a Clunking like metal on metal clunk coming from the bellhousing/transmission. It drives fine though higher rpms and everything, just vibrates coming to a stop.

Just had it apart, the adapter sleeve is in awesome shape, I forgot to mention too that in my shortbox i had a 465/208 setup, I installed that in the blazer but it was to long of a set-up, so i had to get the 465/205 i just un-bolted the bellhousing and slid the new 465 in

[Big J]

You might get more help if you post this or a link to this in the All 4x4 Tech & Off Roading section. Wish I had more info for ya. Someone will chime in. Could be anything from a bent wheel to a warped flywheel. With the drive shaft you might pull the front, run it with just the rear drive shaft to see what happens. Then pull the rear and run the front shaft going straight down the road to see if its the rear causing the prob. Just some thoughts for ya.

[bigbadchev72]

It is totally in the bellhousing area.

[Critter]

Originally Posted by bigbadchev72

It is totally in the bellhousing area.

Does it act differently if you are crusing in 4th gear, let off the gas and apply brake as it does in the same conditions except you push in the clutch? In other words does the vibration change any depending on if the clutch is engaged or not?

You suspect it is in the bellhousing area so I'm guessing you have ruled out the obvious bad tire/brake issues.

[bigbadchev72]

It only does it 15mile an hour and below comming to a stop. It feels fine cruising and taking off, does it with the clutch pushed in too. Not the brakes or tires, I have had this vibe through 2 trans/xcase(same clutch) 2 sets tires, 2 drivelines

[TonyJohnson]

Have you had your alignment checked?

[DANTES JIMMY]

if it does it with or without the clutch engaged and it is not in the tcase it about has too be in the tranny itself doesn't it??

[bigbadchev72]

I just bought another blazer today, will be picking it up soon. Has a 350/205 combo in it. we will see what happens.


I have never had it aligned, but it drives straight and tires wear even. I pulled the tranny hump today and drove it around the block, the front hubs unlocked the front shaft spins?

[Long Roof]

Think thats normal.

[TonyJohnson]

Originally Posted by bigbadchev72

... the front hubs unlocked the front shaft spins?

If you have the transfer case in 2wd, the front shaft shouldn't spin if the hubs are unlocked. The hubs may not be unlocking.