How did you make sure?
Did you take the s/c apart and see for yourself?
The tensioner pulley is easy, just requires some man-strength. *cough* 20-30 bucks. The M90 is serviceable, it's just that the bearings are something of a pain in the ass to repair, and most people will just say f* it and replace the whole snout.
I honestly would start small and just replace the s/c coupler with the one from ZZP. If it still makes the noise after that, then it's the bearings, and you have a good s/c coupler that won't soon wear out like the GM one. If the noise goes away, you just saved 300 dollars.
Herc made a good point, you stood against them on the 1500 BS and they backed down and said it was something else, still expensive.
Odd, no?
Well, in conclusion, you can change the pulley yourself, and if you want to throw away your money without seeing for yourself what the real problem is, that's your choice, but if they're lying and you get screwed, remember that it was your choice.
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Originally posted by HercMan:
Sounds like corrosion has had it's way with your nuts.