kmagnuss

Selling my car and the potential buyer had a ppi done. Came back pretty good except the tech said it has a pinion bearing whine... he has "heard it a thousand times". Well the only thing I can hear is what sounds like an alternator whine that alternates with the revs but it is rpm dependant, not speed dependant. Would a pinion bearing do this? I figured it would be more speed dependant.

Thanks.

-Mag

Mark I

No

kmagnuss

Yeah I figured. The tech was sort of a knowitall deuche... typical mechanic attitude "I know more than you because I'm a mechanic and you can't possibly know anything without being covered in grease". Well I was a shop manager for a commercial construction repair shop for years before getting into sales and can fix most anything I come across... and I love the internet. I get the same attitude from new mechanics we hire until I show them how to fix something they can't figure out on their own.

He also potty mouthed my Function First motor mounts and transmission mount... so far as to say "your transmission mount is broken... that's why somebody stuck these fillers in there." And I said "I did that, and it wasn't broken when I put them in. Can you show me where it's broken or are you just guessing?" Then he went on about well I can't really tell that it's broken followed by a lesson in how it works.... yeah man, I know how it works.

Mark I

So, what's your strategy to deflect the PPI mechanic's pinion opinion? I'd start by duplicating the sound with the car parked. Then, remove the belt - sound should be gone, if you're alt bearing theory is right. Confirm by feel/ sound of bearing when rotated by hand. There was a thread no too long ago about a good quality alternator at a reasonable price at a national chain. GL with resolution!

Macster

The pinion bearing noise question has been answered. You need to find another tech.

My limited experience with my 2003 996 Turbo is any noise that could be taken to be alternator (or power steering pump) whine is probably a noisy idler/tensioner roller bearing.

My Turbo has gone through two sets of idler/tensioner roller bearings in 145K miles. (My other car, my 2002 Boxster, is on its original idler/tensioner roller bearings at 300K miles.)

You can't dismiss a water pump either.

I have to say based on my info is more water pumps fail than idler/tensioner roller bearings (my Turbo is the exception: 2 sets of idler/tensioner roller bearings, one water pump, but my Boxster has one bad water pump and no bad idler/tensioner roller bearings); and more idler/tensioner roller bearings fail than alternator bearings.