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Burntboot
02-15-2012, 09:56 AM
So I spent a ridiculous fortune having my fr drive-shaft "renewed", was promised it would be better than new and last forever.
All I really got was the shaft.

Bottom line is it needs to be balanced, found a shop, pulled the shaft and drove for an hour just to find they can't do it.
On the upside he noticed one of the joints wasn't installed properly and he corrected it without charge.
Then he said why don't you just sell it the way it is?
I was a little perturbed at his remark.
He explained they only time HE does repair like THAT, is to sell a vehicle, as it's life span is 6mos, maybe 2 years tops.
I was sad and explained my sorry situation.
He said it really wasn't worth spending the money (~$150) to balance it.
He told me just to balance it myself, all I had to do was run it in gear, hold a piece of chalk to the shaft and it would mark a high-spot, apply weight (1/4in washer) to the opposite side with a hose clamp and retry.

To me, this sounded like total BS but without other options....

I pulled it up on ramps and lifted the back with stands under the axle, to have it level without the fr axles hanging.
UNLOCKED the fr hubs (this is VERY important) then ran it in 2nd gear, 4WD HI.
(I had to look to see if the shaft was spinning as I could not hear anything, big change from before the spindle bearings)
Helps to run a piece of 40 grit sandpaper against the shaft to have a clean spot for testing.

When I started I had a chalk line about an 1/2in long, I started with a hose clamp and 1/4 flat washer.
After way too much time, I have a chalk line all the way around, though it varies from thick to thin. (1/4 and 3/8in washers)
Decided it was time for a test drive, before wasting anymore time.

What had been noticeable at 60K and unbearable by 90K, is now merely annoying at 95k+.
The whole ride is a lot smoother over a broader range and most of the harmonic noises disappeared too.
Clearly, I have a little more work to do as I suspect that that little line should be fat all the way around.

May be useful for those trying to solve vibration problems as it provides another tool to eliminate some of the variables.
Not too mention, a low budget way to deal with it, if it is an issue.

BB

timsrv
02-15-2012, 11:04 AM
I too have used this method to balance shafts. It sucks there are guys out there that do shoddy repairs. I spent $300+ on a drive shaft one time and the welds looked like a high school kid did them. It was disappointing, but not much recourse except hoping for the best or finding another shop :no:. Tim

Harbilly
02-18-2012, 08:10 AM
I know this problem too. I bought a 4runner new in 88 that had a driveshaft vibration problem right at 55mph. The dealer reversed the shaft and it changed the vibration to some other annoying spot (I can't remember which) but that speed too was a common one when driving. Eventually Toyota put a new shaft on. And now I find a hoseclamp, a washer and a piece of chalk was all that was needed?I'm not really clear on how to use the chalk from the description here but we may all be using this method soon as our drive shafts can't last firever and more and more of us are going to be heading down the 'rebuild' route.

timsrv
02-18-2012, 12:01 PM
When a drive-line is out-of-balance, at speed the heavy side will pull away from the center and the light side will pull toward the center. The chalk is simply a way to mark the heavy side. When you get the drive-line up to speed, carefully hold your chalk up, and only the heavy side will touch it. A well balanced shaft will make 360 deg contact with the chalk. Tim