Should a PPI Uncover a Bad 3rd Gear Synchro?
 

I've determined my car has a bad third gear synchro. When you shift into 3rd at 5,500 rpms it will grind unless you take about 5 second to shift. Before I determined it was the synchro I went out tonight and adjusted the gear shift. I adjusted the gap between the slide ring and selector rod head to 5mm as stated in the shop manual. It made my car shift so much better and even helped the problem I was having. However, I still get that grind going into third though now I only need to slow my shift down to about 3 seconds.

I had a PPI done and they didn't uncover it. Is this something that should have been found? I wouldn't have paid what I did for the car if I had known about this.

Thanks,

Scott

p.s. G-50 tranny

Probably not. Try a fresh fill of fluid before you determine its done.

I took mine to a Porsche dealership for it's PPI. They were spot on with everything. 1st synchro was shot (had to come to a complete stop or match revs to avoid the crunch) and 2nd gear was balky. I told them to test every switch and guage in the car. They picked up on windshield washer, interior light, fog lamp. The only thing they missed that I found was a missing interior temp sensor.

A faulty synchro should have been noticed. It must feel a bit different than the other gears even with a short shift, though? How long did it take you to find?

I noticed it probably the first or second day I had the car. It does it everytime you shift into third at a high rpm unless you are very careful. I would think that checking 1st, 2nd, and 3rd gear synchros would be part of a standard PPI.

Scott

Hi Scott,

You said in your post that it grinds when shifting at high rev, I doubt that the tech doing the PPI would go out and drive your car like that on city streets. The car probably shifted through the gears ok for a normal test drive. A normal PPI would not open up the transmission to inspect, unless that was a particular concern that you stated and asked them specifically to do. If a worn synchro is all you have to replace, that is not so bad. If you find out in two weeks that the valve guides are worn and you need a major engine top-end overhaul, then you have real problems.

One thing that I have heard often here, do a fluid change with Swepco 201. It might make a noticeable improvement. Also, when I was first getting used to driving my car I would grind occasionally going from 2nd to 3rd. I quickly caught on that I needed to let the shifter get up to neutral and feel it up against the right side before pushing up. After I got the feel of it, I have not grinded again.