ronnie993tt

I'm no expert and I basically learn from you guys, who incidentally got me onto M1 V Twin. Anyway, I finally had a chat with my tech at EU Autowerks in Toronto and they use the stock non-synthetic 75W90 transmission fluid pictured below. They (and Porsche apparently) do not recommend the synthetics because they are too slippery and do not allow the syncros to slow down fast enough, causing notchy shifting. My shifting is buttery smooth with this stuff. What do you think?

rlme36

I just did the change in mine with the delvac gear oil based on the recommendation by a few members. I haven't driven the car since the change but expect it to be the same since it meets the gl5 reco of Porsche

KM

I also changed my gearbox oil recently and used Delvac. The balkiness when shifting into 2nd while cold is gone. Had it on the track Monday and no issues whatsoever.

badabing

I'm about to fill with Delvac as well based on a conversation I had with Steve Weiner.

Mike J

I did not know what was in the car when I bought it - but the shifting was very good. I changed to Delvac SCH and it changed the transmission feel - balky when cold and definitely not as smooth shifting. I have to try a few things to get that smooth feeling back. Given it was only about 100 ft difference between the old oil and the new oil, the oil was the only thing that changed.

I heard 999.917.546.00 was pretty expensive - around $25/litre. I talked to Sunset about transmission lubes, they said there are a few options:

• PTX only comes in 20 liter containers $472.78 - $23.60 liter - 000-043-204-20
• Porsche also has Shell oil 75w-90 in 20 liter container $399.11 - $19.95 liter 000-043-204-19
• The shell does come in one liter container for $25.38(we normally have this in stock) 999-917-546-00

I also have some Redline in the shop which i will try, as well as Swepco.

These transmission definitely need to be treated on an individual basis, they have personalities, especially the more worn ones. you just gotta find what YOUR transmission needs for its care and feeding.

Cheers,

Mike

P-daddy

After changing out to Swepco last winter, my trans feels very notchy when cold. I may try the Delvac this winter.

Basal Skull

There's two problems I can see with changing tranny fluid and assessing how well it works. One variable is to make sure the trans is full. You really have to spend some time to fill things slowly and recheck. I think a lot of people don't fill properly and have changes in trans character due to incorrect level. The other problem is (I know this from testing engine oils) changing fluids once does not get rid of the old fluid/additives. Some of the effects of the old fluid is still present for multiple fills. The only way to really see the effects would be to persist with a particular fluid type for many changes or open the trans up and wash each gear with solvent prior to changing.