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Matt99XJ
August 13th, 2003, 11:32
OK here is what i have done to diagnose the problem.

I have a horrible hum/vibration over 65 mph. it gets worse the faster i go. The whole vehicle vibrates. It vibrates the change in the cubholder and the keys. It is a really low hum/drone.

I pulled the front shaft and it is almost gone but still noticable. You can tell it is coming from the front with it off.

1. I balanced the DS and changed all of the U-joints/Centering joint.

2. pinion angle is .5* below DS

3. pinion output has no noticable play in it.

What else should i check? Hub/bearings would grind right?

My tires don't balance very well, could it be them? The shake a little bit at 50-55mph.

Fore Wheeler
August 13th, 2003, 12:23
Originally posted by Matt99XJ
I have a horrible hum/vibration it gets worse the faster [she] go[es]. The whole vehicle vibrates. [wow!] It vibrates the change in the cubholder and the keys. It is a really low hum/drone.

I pulled the shaft and it is almost gone but still noticable.


life aint that bad, what's her name???:D

Matt99XJ
August 13th, 2003, 12:24
:D :D :cheers:

Matt99XJ
August 13th, 2003, 18:50
anybody?

MaXJohnson
August 13th, 2003, 19:40
Tires out of balance wouldn't result in a hum, but if the tread is cupped or feathered that could potentially cause a hum. The frequency of the hum should give you a clue since the drive shafts spin at 3 to 4 times the rate of the wheels.

If you have weak main leaves in your rear springs, you might be getting more spring wrap than the 1/2° can compensate for. Spring wrap doesn't just happen under acceleration, it is there under constant power too.

XJeff
August 14th, 2003, 04:39
If it's a humming coming from the front end and it increases with speed it's probably your wheel bearings. I had the same problem back in Feb.

I picked up two new hub assemblies from Autozone for $90 a piece and 2 hours later problem solved!

hth!

Matt99XJ
August 14th, 2003, 08:59
Hmm... I think you might be going somewhere with the spring wrap thing. I was driving it last night and if I let off the gas completely it stopped. The springs i have are soft but I don't think they are worn out. The rear pinion is almost 3* below the DS. Do you think it could be moving that far?