Drive Line / Shaft imbalance question

[shimmersky]

I had my drive line replaced in early 2007 with a unit that tom svx helped me procure.
The original symptoms of failure were bad joints and an imbalance that caused a rumbling vibration at slow speeds and some strage stuff at super high speeds(over 100)
The replacement driveshaft came with zirc fittings that could be lubed as the stock unit does not??
The exact same symptoms are rearing their ugly head again.
THere seems to be an imbalance in the shaft causing vibration at slow speeds and the reconditioned shaft seems to be rusting in places after a bad paint job.
Just shy of 22000 miles on the reconditioned shaft??

Any advice on where to procure a good driveline??
Any place that sells these parts off the shelf???
Any ideas on the reason for these failures???

[SoCal LS-L]

How often did you lube the grease fittings?

Driveline patch rust is common, anything under the car is subjected to the sandblasting effect of highway dirt and debris.... its usually not a problem as the outer layer of oxidation becomes a protective layer.

Since the lower speed vibration has returned, which under throttle is a symptom of binding, try lubing the fittings and see if the symptoms go away.

If not I would at least ask Tom if he can set you up with another one for a discount, it never hurts to try.

[shimmersky]

The new drive line lube fittings were serviced every 3000 miles with the engine oil.
I was actually happy to be able to lube the joints as the stock joints were not serviceable.
I have just sent off a pm to tom svx in hopes of trying to troubleshoot this strange issue??

[ShiuludeSVX]

I tried the replacements, and thought it was gonna work, but ended up with a 55 to 65mph "unsweet spot". That was terrible.

I talked with a shop, and he made a call to CA., with a result of custom shaft for $500. I couldn't do that, so we talked somemore.

The shop here was able to pull shelf parts, and hack the ends off my old blown drive shaft, and added greasables and a balance for $340. It's only been about 500 miles now, but my drivetime is a lot more bearable without that rumble.