Qtonic

This is weird, but follow my logic here...

I understand it's commonly known that the Tiptronic takes different fluids for the ATF and differential.

ATF: often Pentosin ATF1 or ESSO ATF LT 71141
Diff: 75w-90 Synthetic Gear Oil (99991754600 superseded to 00004330549)

But I've seen several places that 99991754500 (note the 5, which was apparently another p/n for the gear oil -- see http://www.porscheatlantaperimeterpa...991754600.html) has been superseded to Pentosin ATF1.

http://www.pentosin.net/pressreleases/PENTO001_ATF.pdf

and

https://rennlist.com/forums/boxster-...l#post10094325

So by logic, if 99991754500 is ATF1, and 99991754500 and 99991754600 (the gear oil) are the same, then ATF1 is now the same as the gear oil?

Now maybe Wayne from Pelican got the part number wrong in that 986 post and accidentally gave the diff p/n instead of the ATF. But then there's that PDF from Pentosin, and multiple other places (such as https://www.autoparts2020.com/pentos...f1-pol-1058107) that do seem to equate 99991754500 with ATF1. And ATF1 is 75w ( )

Anyway it got me thinking. How could the same p/n be referenced to both the ATF fluid and the gear oil? I'm not trying to get around anything here or avoid using something, I just find it interesting. Thoughts?

Mark I

ATF and Diff fluids are NOT the same on any tiptronic. However, the ATF differs from the Mk I and Mk II tiptronics.

dporto

Ummmmmm... no

Qtonic

I feel like my intention is being missed here, lol.

But no one has yet really addressed it.

Porsche claims 99991754500 and 99991754600 (gear oil) are both superseded to 00004330549.

Pentosin and plenty of other places claim ATF1 is a replacement for 99991754500.

Something doesn't add up.

dporto

Why do you need to make this more complicated than it really is? ATF is ATF... Gear oil is Gear oil... jeezzzzzz

Billup

But what oil should we use?

DBJoe996

I see what you did there!