Manual Transmission Fluid - Best Brands?

[chitowndad]

It's been a really long time since I posted on this site and I know the question has been asked before but I couldn't find the answer...

What are the best brands for manual (6 speed) transmission fluid? I have 23K miles on my 2001 and I can tell it needs replacing.

Should I use Redline MTL 75W90?

Thanks,
-Steve

[Steve Tinker]

There have been lots of discussions & opinions on this - but why would you replace the Porsche gearbox spec oil with something else?
Use the search function and I'm sure you will find many opinions on GL4 vs GL5 specs.....

For what its worth, my local OPC changed the gearbox oil (by my request) on my '01 Boxster S 6 speed when I purchased the car from them. They use Mobil synthetic 75W90 gear oil out of a 40 gallon drum & when I queried it, the tech said it was "as good but cheaper than the Porsche stuff" - I believed him.

Fast forward 3 years and 10,000 miles later, last June I replaced the gearbox oil with the genuine Porsche lubricant as I was not happy with the notchy cold shift action. The difference was immediate after the first cold start - the Porsche lube is superior to the Mobil product in all temeratures !!
I will not go back to aftermarket gear oils again - especially as you only have to change it every ~90,000 km anyway.

[Flavor 987S]

Just had mine done Friday. 2006 987S with about 45,000 miles. I used OEM. Bought 3 quarts from Sunset. About $24/quart. Will do UOA on the drain sample.

[JFP in PA]

Originally Posted by chitowndad

It's been a really long time since I posted on this site and I know the question has been asked before but I couldn't find the answer...

What are the best brands for manual (6 speed) transmission fluid? I have 23K miles on my 2001 and I can tell it needs replacing.

Should I use Redline MTL 75W90?

Thanks,
-Steve

We spend an inordinate amount of time draining just about every brand of after market gear oils out of Porsche gearboxes in one failed experiment after another. Every time, the customer comments are the same: Poor shifting, stiff, noisy, etc.; and every time the results are the same: The problems go away as soon as the OEM product goes back in.

A lot of small time lubricant blenders claim they can match the OEM product, yet the major players in the lubricant markets say they have no direct match for Porsche’s product, which has unique characteristics and is made by a small specialty manufacturer, and has no GL or other recognizable specs, but is a full synthetic product and obviously works well in these transmissions.

[ASpec818]

wow 23k miles on an 11 year old car?

Royal Purple is pretty popular amongst the message boards.

[chitowndad]

yep only 23K miles on an 11 year old car... I drive it on the weekend, 8 miles to the train station with underground parking and store it for 5 winter months...

-Steve

[Flavor 987S]

Steve, what fluid did you have put in?

[chitowndad]

I hope to change the fluid this weekend. Most likely I'll put in Royal Purple 75W90.

[Brucelee]

Yes on the Red Line.