Bus

Yes... let me also say; Thanks! I'm learning a great deal that will help me in the future when I try to tackle this task!

BC

John - I am having a problem finding those differential bearings. The ones I got from the LSD I have are 533060 *** tapered roller bearings. Did you ever look around for those?

John V

Brendan -

No, I was able to re-use mine from my old unit. I still have the one junk one that I took off the LSD if you need any part numbers. I would presume you need to keep the bearings and races matched?

BC

I made a bumbo this morning and only brought the bearing itself for work without checking if the race is labeled inside the hub (Number 11)



I think it shows there that there is obviously a race in the pressed-in piece that contains the seal on the trans. I bet that has more info then the "533060" that is on the tapered roller part. I bet the race has the bearing info.

Mine were a bit....brown.

BC

I think its these:

http://cgi.ebay.com/ebaymotors/ws/eB...ayphotohosting

John V

Damn Brendan- Nice find! It looks like the race comes with the bearing (at least it should). BTW - you might want to order some of item #8... I re-used mine when I swapped ring gears but they didn't look great having been pried off, striaghtened and re-used.

BC

I destroyed them. I suppose I should order more. Thanks.

BC

John - Do you think that a combination of the Goetz Sycnhro, and old selector rings is better then the non-goetz sycnchro with new selector rings? Which is the long-term wear item? The 2/3 part that I have is the goetz part. I have been buying other parts like the bearings and the blown bevel gear, but now I really do need to buy the second 2/3 and the two selector rings, etc.

TIA

John V

My inclination is that a new selector sleeve and new Getrag synchro will outlast a new Goetz synchro with old selector sleeve. You can see in my pics that as the selector sleeves wear, the surface becomes rougher and deforms into the adjacent grooves. I'm inclined to think that this rough on rough abrasion, of questionable profile will accelerate wear of a new synchro. I haven't touched on this but my car had an occasional tendancy to "stick" in 3rd gear. By stick I mean that there was a catch of some sort when trying to shift out of third gear (like the clutch was dragging)... It would come out with just a little more shifter effort but you could tell there was something preventing 3rd from releasing as easily as the other gears. At first, i thougt it was the clutch dragging but only 3rd gear did this and to rule out the clutch, I shut off the engine to see if it would free up and it didn't. This indicated to me that it was something in the gear, or linkage. After doing this rebuild, I'm inclined to believe that shift sleeve may have been the problem but I won't know for sure until I get the box installed. I can tell you that I was able to recreate the problem on the bench prior to the rebuild and now, it seems the 2/3 selector sleeve disengages much smoother.

I should have also pointed out that I only sampled 1 Goetz synchro ring. That 1 ring measured .010 thicker than the 4 other Getrag rings. BUT, it's still only a sample of 1... that .010" extra thickness may have been an anomoly. If other Goetz synchro's come in at dimensions closer to the Getrags, than they may not adequatly improve synchronization when used along with a worn shift sleeve.

BC

John - I could be measuring this wrong, but my 2/3 part is .170"

You are measuring the total height of the part from ID to OD right?

BC

I just measured the synchros I do have, which are 1, one 2/3, and a 4. All are within a bit of .170" thick total. I bought these last year.

danglerb

Do you have a lot of confidence in those really fitting and working well, it seems like it could be more "here is a bearing with specs within tolerance of what should fit these cars" instead of a Porsche bearing, or is this something of a generic part?

Why I ask is that the main snag to me having my 83 5 spd rebuilt is the cost of the input shaft bearing, ala $500. If I could find a more reasonable replacement it might change my mind, or prolong my agony of indecision anyway.

I need to check and make sure which 5 spd I have, 83 is I think G28:08

John V

Brendan,

the measurement that was a problem on mine was the leading edge. The synchro has a cross section where the inside is flat but the top side actually has a step, a riased plateau and a down sloped ramp from that plateau to the leading edge. Its the height of that leading edge (and to a degree the slope of the ramp) that was different on mine. If you measure the thinest part of that ramp, it should be around .160"... the one Goetz that I measured was .170" at the leading edge (almost no ramp) and it just wouldn't even start into the shift sleeve. There's a pic of where I measured in one of the previous posts.


To the second post on the bearing, it's hard to say. I didn't read the ebay listing, I just presumed it was a direct replacement. As an engineer, I can tell you bearing technology is anything but simple. The same general bearing is available in numerous accuracy ratings and preloads that all equate to a specific application for speed, load, heat and/or precision. In a machine tool spindle, one accuracy grade off and the bearings may not last a week wher the correct one will last 15 years. Having said that, these bearings don't appear to be in an ultra critical application for load, speed, heat or precision so they will likely be just fine. The only concern I would have is that the transmission case is shimmed to produce a certain amount of preload. New - equivelant bearings may effect that preload and require different shims. keep in mind that preload and backlash are independant of each other. I hope that helps.

BC

The bearing is a certain dimension no matter who it is made by. If it is published via the ISO (or whatever - I'm not an engineer - I'm a Financial Guy - JohnV is the engineer here) info. These are Koyo bearings, so they should be okay. I have gotten prices from 25-50 dollars each, so these will do.

The part number they list as well is exactly the part number that is on the race, 32010x.

The ones on mine were a bit burned. I'm not sure how that happened. Every time I open these cars up its like a anchropological Dig.

BC

I did not understand that. The Goetz 2/3 I have from PAP is a TOTAL of .170, but indeed the initial step dimension is right around .160. It actuall lets the calipers go .05 into the metal before it stops if they are set at .160.

So I guess maybe you were right and this WAS a wierd part?

Thanks again.