Getting ready to do a bunch of fluids. Looks like everyone is using Mobil 1 75W-90 trans fluid. Book says 3.6 liters for a full change. Does that sound about right?

 

To be clear, Mobil Delvac 75W90........not Mobil 1 75W90.

 

I will try the Delvac when I change fluids this winter. I'm running Swepco now. Its way too "crunchy" for me on colder days.

 

I don't think you'll find anything on this forum that "everybody" uses - especially when it comes to any kind of lubricant (automotive related). Yes, a lot of people use Mobil 1 75W-90 (me included) and a lot of people use Mobil Delvac 75W-90, as well as many other brands.

If you haven't seen it here is a good diy:
http://www.pcarworkshop.com/index.ph...ion_oil_change

 

Not going to recommend a fluid but I will (highly) recommend you remove the fill plug before you remove the drain plug.

 

Thanks to all.

 

3.6 liters sounds right...

 

Each bottle of Mobil 1 is 1 US quart = 0.946 liters. 4 bottles will do it.

I use Mobil 1 Synthetic Gear Lube LS, 75W-90. The Porsche owners or repair manual does not get into specifics other than weight.

 

what would Porsche have used back in the day as a fill from the factory, for gear oil, brand wise?

 

I wouldn't put the normal Mobil 1 gear lube in anything... Delvac 1 is the way to go.

I ran normal M1 in my diffs on my 4runner- after 25k miles, the fluid was black and smelled burned.

Same interval on Delvac 1 and the fluid is still pretty much clear.

In addition- all of the rebuilders say to use Delvac- Copans is one of them IIRC.

 

I used RedLine 75W90 NS and do it again.

 

But the Cup and RSR manuals do
Delvac which used to be called SHC is specified

 

Is it possible to overfill? Why would Porsche design something that required us to fill it and quickly reinsert the plug to avoid spillage?

BTW: Delvac is not too easy to find.

 

Unless you flip your car onto its right side you can't over fill the tranny. No need to quickly reinsert the plug. Fill until the oil is level with the bottom of the opening and reinstall plug at your leisure.

You may need to check with a local petroleum products distributor to find Delvac. I get mine from the same local distributor I get my Brad Penn from. Delvac 75w-90 comes in a case of four 1 gal containers. My distributor opened a case and sold me a single gallon.

 

L&N Engineering sells it. So does Petroliance (4 gallon min order, split with a Rennlister).