gruffalo

I'm considering having the manual transmission on my '81 rebuilt. The synchros on 1st an 2nd are weak, and oil is sweating from the diff and somewhere up front (as from what I can see). So at least I'm looking at synchros and a gasket/seal kit. The 1st and 2nd gear set cost more than my whole car probably, so I gonna have to try to avoid replacing those. I'm gonna remove the tranny myself, so I'm only looking at labor costs for the work on the tranny unit itself.

Are there any drawbacks to replacing just the synchros?

Any other recommendations befor I kick this job off?

mm

rixter

mm,in
no drawback as long as the gear sets and bearings are ok, if you need either let me know I have a 5spd from a 78 that is already out and in pieces..
as for doing it yourself.. I hope you are strong because that rear end weighs about 900#s
best of luck

Jim bailey - 928 International

Yes the worn synro which fails to match the speeds of the two gears causes the engaging teeth (dog teeth) to get worn. The grinding sound you hear when shifting is NOT the syncro ring making noise but the TEETH being ground away and bent to one side. Quite often, the damage will have worn the shifting sleeve. The longer it was driven grinding the gears after the syncros wore out the more damage there will be. Porsche does NOT sell the engaging teeth rings separately we do. Figure $195 for each. Changing only the worn syncronizers may improve the shifting but not make it shift like it did when new. An experienced Porsche trans rebuilder should be able to determine how much damage has been done and what needs replacing BUT very rarely is it just syncros !

gruffalo

Jim: since you sell the engaging teeth rings separately, does this mean I can avoid the $3k 1st and 2nd set?

rixter: great offer! have you actually run that 'box? are the gears etc OK?

MM

Jim bailey - 928 International

Correct you carefully cut off the worn engaging teeth ring and press on a new replacement. They are separate parts but Porsche only sells them with the gear sets.