The Fixer

I understand why Porsche recommends what it does, it is to protect the diff,
i also have read GL-5 and synchro transmissions don't get along well.

Redline states some of their GL-4 MTL"can be used where GL-5 75W-90 is recommended".

If Redline GL-4 MTL didn't cause leaks in 928 transmissions, I'd try it for around town use, not for track abuse though.

It's funny Guys use this Redline in '80s 911 trans-axles and I haven't heard of it causing leaks.

Gl-5 protects the diff gears better than GL-4,

GL-4 would allows easier synchronized transmission shifts. This is the issue.

But I am in agreement, I am just curious what Greg thinks about adding a little GL-4.

Best for me just to try it.

LT Texan

If the problem goes away once the transmission warms up a bit, why would it be the clutch.

Maybe the shop put in the wrong gear oil.

I've used Swepco in my transmission ever since it was recommended by (of ****, I forget, could it have been DEVEK?) for the older style syncros.

No problems here.

GlenL

Because the clutch is warming up, too.

jbrob007

I've chased this monster around the block for a year... clutch adjustment is crucial and we've done it four times. I've tried every damn oil out there... Redline was best for shifting but made my tranny seep oil... Mobil 1 is good stuff but not as good as Redline... Went back to petroleum oil "because its supposed to work better with synchros"... NOPE... then someone recommended Royal Purple (most expensive snake oil in town) - its good stuff but no better than the other synthetics above. I've come to the conclusion that I have a synchro issue or two especially # 2 gear...

R.Pires

Hi,
Did the grinding when cold go away finally?
Do you still have to wait a while or it’s ok immediately?

Regards

hacker-pschorr

Read my posts again, I've been in this situation more than once with my 81 and it was the clutch each time.

Lizard928

Hacker and Greg are right.

Fix the clutch first and foremost!

aebs

The grinding has improved to at most a 5 minute warm up when cold. Sometimes 1 minute.

Lizard928

Fix it properly and that will go away entirely.

aebs

I just dropped it off at a new shop...

The Fixer

I know this thread is more about your clutch adjustment..

But i drained and refilled with Mobil 1 75/90 LS and my car shifts great with it. Just got back from the first drive.

I didn't realize i used that in my 911 and liked it in there. I found 1/2 liter from about 4 years ago, went and got 3 more. It's cheap too $10.58/liter at Autozone.

The Fixer

Since everyone likes pictures in these tech threads:
Prefer gravity doing the work to pumping.
Sorry about the size. will re-size next time.

R.Pires

Did they solve theproblem? How?

aebs

Not yet. It is now getting some other work done first, so it is drivable.

So far, the original shop says they used all new parts. If that is the case, then it is not put together right. In addition to it having to warm up forever, the pedal is even too heavy. The first shop took about 1.5 months with it, so I'm not too interested in bringing it back there again. The new shop knows what they are doing, will post an answer soon.

Anyone else has one where the pedal is too heavy?

R.Pires

Hi,

Thanks for your answer, please let us know what happens!
My car also had a complete new clutch (the 2 discs, intermediate plate, pressure plate, release bearing, secondary and master cylinders, blue hose)
I'm having an almost identical issue, but my pedal feels perfectly normal all the time, so I believe the clutch is well bleed.
My problem is that it's impossible to get in any gear until the car reaches normal operating temperature.
When it does, suddenly like a miracle, I can shift all gears, upshift, downshift, no grinding at all, it's perfect!

Regards