desdain

Thanks for your comments. I'll post the results as they come in...

desdain

Okay, I got the wheels balanced and it seemed like the guy had to add a lot of weights to them. Anyway, the balancer showed perfect and I took the car out for a test drive. Long story short, no fix. If anything it seemed like it started vibrating a little earlier (at 55mph).

Next I'm gonna put it up on jack stands run it up to 60mph on the speedo and then start removing stuff until it stops vibrating (first wheels, then discs, then drive shaft, etc.). With my luck this is something that only happens when it under load :-(

Anyway, keep the suggestions coming.

Gun Jam

I had a bent axle once...

Its easy to check for take the wheel and drum off and placed a fixed indicator of some type so the point just touches the flange. A center punch C clamped to a solid free standing object works well.

Rotate the axle and watch the point if the axle flange runs into or away from the point you have a bent axle...I could clearly see the runout on the axle using this method...it was .009" out of round and was very noticeable. I bet this could be your issue.

-Gun

dagamore

My father had an old truck (1976 F150) that had a nasty vibration to it from 45-65mph, it was a failing Ujoint. It might be worth it to look at them.

desdain

Quite possible, they were pretty bad, but we were able to fix them to the point of ~no wobble. It's down to 0.05mm now, but I'll probably have to replace them during this coming winter, I just want to get is "pretty good" for this summer.

desdain

Yeah, this could also be an issue. The front u-joint is new, but the rear is the old one. It looked okay though, and now that it's been tacked into place, it's hard to replace. I think I need to borrow a good driveshaft from someone and try it before buying a new one.

Gun Jam

wait....what?

You were able to fix them? as in the axles were bent and you made them straight?

how many mm did they run out before you fixed them?

How did you fix them?

-Gun

P.s a 1/2 mm is .0196" runout it was pretty bad at .009" (inch) in my case and .002" is maximum allowable

Reality check!!! you are 194 thousandths above maximum allowable runout
dont mess around replace both axles and bearings.

boeing747arowair

on my 6 banger one of them was out of whack. Extremely hard to find replacements. threw the sucker on a lathe and made them a bit better. Obviously difficult if you dont have the machines or tools

Gun Jam

just to make sure you fully appreciate the axle situation let me state it this way...



you are 9700% above tolerable upper runout limit

I hope I have reached you

-Gun

desdain

We quickly heated up the "concave" side of shaft and it pulled it self more or less straight, but not enough heat to compromise the integrity of the steel. Then we also milled the flanges straight.

Btw. it's 0.05mm not 1/2mm, so that's 0.00196'', which is less than the maximum allowable 0.002'' you mentioned.

Thanks for the continous feedback. It's really appreciated.