I can verify this, as I just rebuilt my 915, with 235k miles on it. It STILL worked great. But, I lost my speedo and it turned out I had 4 magnets pop loose on my Speedo ring, so it was time. Luckily, no damage done .
$6000 parts and $1500 in labor. All new speedo mag ring ( direct from Germany$$) new bearings, dog teeth, sliders, Torque Bias LSD, after market one piece bearing retainer, and a used 7:31 R and P, and a 912 5th gear ( Tall, for highway milage). Oh yeah, new clutch too. It was extremely difficult getting the right shims and mesh pattern, but we got it. It's solid. It may not be much faster, but it sure gives me the illusion and I love the pull it has in every gear. (except 5th) The LSD was the best mod I have ever done. Power in the corners has a whole new meaning. But yeah, freakin' EXPENSIVE!

 

Not far from what I thought it would cost .. makes you want to be careful though ..

 

It's difficult to install a 7:31 into an 8:31 housing; the head of the pinion shaft (with only 7 teeth) is much smaller, which requires an unusual offset of the diff carrier, done with the mentioned shims, to move the ring gear to a position where the correct backlash can be obtained. Certainly not a mod for the timid!

 

I have an 83 SC with the 915 transmission. What are some good oils to use when changing the oil? I cant get Swepco 201 locally, so please tell me what others are good. Castrol? Valvoline? Thanks in Advance.
Brad

 

Brad:

IMHO,.....Make the extra effort to get the Swepco and you won't be sorry. Its FAR better than anything else in these particular transmissions.

 

Steve's right, but if you absolutely, positively can't find it, I would certainly favor Kendall - just DO NOT put synthetic gear oil in it!

 

Thanks. Ill search for Swepco.

 

recordman: Was the one piece bearing retainer the Wevo part? If yes, how did your mechanic like working with it?

 

Pete, yes a nice Wevo part. He had no comment on the one piece retainer, probably because getting the right length ring bolts and shims to get the backlash right was such a huge pain in A$$. He said it was the hardest 915 he's ever done. He considers himself a 915 expert.
I can't say enough good things about the Guards torque bias limited slip. It's great for the street AND the track. Awesome.

 

Thanks for the follow up, that's good info.

 

Peter this is as good a place as anywhere to tell you Red Line was awsome. Marc was very kind to give me the tour of his shop and take time out for me. He gove me the Kendall limited slip lube in a zip lock bag with gloves on. He says it stinks and "don't keep it in the car for an extra second." He even gave me the replacement washers for the drain plugs. I was welcomed to the family by Carl.( Guy in front shop) He must have walked past a million dollars in Porsches to look at mine. Marc introduced us and Carl said "Douglas, Welcome to the Porsche family" What a thrill! All in all I got two thumbs up from Marc. He noticed my wipers are on wrong as soon as we walked out to my car. I showed him how soft my Bilsteins are in the back and he said they were an add on. I was shure it was on my option code but nope. He said no Bilsteins on soft top cars. Oops, I trust him, but what do you think? I didn't think anything was done. He was even able to tell me how old my fuel filter was just by looking at the print job on it. Too cool. he said my idle has never been adjusted. Who knew? Anyway thank you soo much for the referal to him. I have a play date on friday with my rennlist buddy with the four post lift. Motor oil, tranny oil, flapper box. Take care,

 

Step away from the tool box . Forgive the newb, but what in hades is a flapper box and what are you going to do to that thing? Here's to hopin' your answer is PG.

 

LUCK, a flapper box is part of the heat system. Mine is stuck open on the driver's side not so bad with the top down this summer, but a killer now with the top up and windows 90% up.

 

FOR ANYONE WITH A G50 READING THIS THREAD AND WONDERING IF THEY SHOULD USE SWEPCO:

The answer is no. I believe the preferred Gear Oil of choice for the G50 is now Mobil 1 Delvac 75W90 (atleast for LSD cars). I have a jug of it at home that I had shipped from www.lufteknic.com in Virginia. I will be flushing the tranny and putting that in next week.

 

Oshin, does it matter whether you have LSD or not? I'm pretty sure I don't, but everything I've read says G50 owners should use some kind of synthetic tranny oil.