I'll be changing my transmission oil soon and want to confirm I have the right tools. Anyone know for sure if the transmission drain plug on an '03 C2 manual transmission is:

16mm Triple Square
or
16mm Allen

Also, the fill plug is 17mm Allen correct?

 

Here you go sir!
http://p-car.com/996/diy/transmissionfluid/

 

Interesting that this DIY states 10mm versus the one on RennTech which said 17 & 16mm. 10mm would seem to make more sense, so I'll go with the one you provided. Thanks Red! See you on the Rennlist NY Tri-State 2nd Annual Spring Run (4/27)?

 

It's 10mm. I'm not sure where you got 16 and 17mm...

 

Hello,
I just did this (this weekend) on my 99, and it's a 10mm. I had to use Vise-grips to 'break' the drain plug loose then used the 10mm Allen. No real problem. I thought that the 22 ft lbs was kind of 'soft' for the torque, but that's what I used (the factory must have used 80 to 100 ft lbs). I also put in "just" 2.7 Ls instead of 'until the fluid comes out the hole'.
Hope this helps,
Patrick

 

16mm 17mm... those got to be Ferrari sizes... LOL!

Interesting enough the Ferrari oil drain plugs uses 12 and 14mm allen. Huge drain plugs.

 

993 had 17 and 19mm!

It is indeed only 10mm for both. Make sure you get a decent length breaker bar and an allen socket set - using the hex keys are a bad idea overall when you are dealing with something as delicate as these drain plugs. You likely know this already but make sure to open the fill plug first

 

993 had 17 amd 19mm where?

Of all the 993s I wrenched on I never had to use any 17 or 19mm allen, As I don't even have those two size in my chest.

 

I think people may be confusing the thread size with the size of the allen key required to remove it. The thread size could easily be in the 17-19mm range.

 

Patrick
Did you go with Red Line? I've been pleased with mine. I haven't missed 2nd gear since the transmission change. I can now go up the gears comfortably even when the tranny's cold.
Yes, Magilla Gorilla is alive and well and tightening transmission drain plus at Porsche in Germany!!

 

Yeah, did it this weekend and it's indeed 10mm. Thanks for all of the replies.

 

The instructions on Renntech.org are for Boxster and Carrera. I can tell you for sure the early Boxsters had a 17mm allen for the fill plug and on the right is 16mm triple square with a hole in the middle for the drain plug. We also heard that some of the early (1998) Carrrea's also had larger plugs.

Always best to check what is on your car - Porsche changes things without notice.

 

Yes I did, I couldn't believe how 'black' the fluid was with only 55 thousand miles! Now get this.....I'm all ready to 'bust' the fill drain plug loose...I have the 10mm Allen socket on a 3/8 to 1/2 adaptor and using my long 1/2 breaker-bar; I'm ready to give a 'real' push on the breaker-bar and 'BANG' my hand/breaker-bar handle smash into the bottom of the car................the damn bolt was loose!!!!!! Okay, if that wasn't bad enough, when I take the plug out.....fluid comes out???? Yes, the car was level....as best as I can tell I got a little less then 3 Liters out; I put in exactly 2.7 Liters. Oh, and I guess I should have known because when I took the plastic back cover off it smelled like 'gear' oil...........
Thanks for asking and thanks for telling me about the RedLine oil.
C'ya,
Patrick

 

It's pretty normal for some fluid to come out when you remove the fill plug because you're supposed to fill the trans until the lubricant comes out the hole, not by some specific volume. Assuming the car is level (carpenters level on the door sill is an easy check for that) of course.

 

I found out the hard way on the 996 transmission it is volume specific, the synchros will not work properly if it is over filled.