I want to change oil and trans/diff oils so I went to a local Porsche dealer for supplies.

They had absolutely no idea what fluid goes in the front differential. They said they NEVER change that fluid.

They also told me NOT to open the drain bolts on the turbos. They said that if the turbos are removed from the car, they drain the but fill them with oil before re installing them. They did not like the idea of draining them without refilling the prior to starting the engine.

Comments?

 

i also went to a porsche dealer and they did not even have the Porsche recommended oil for the Turbo. they are putting in 5w-30!!!

 

Speaking of oil, is red line oil any good ?

 

Hi.
The Porsche manual says not to change the viscous
clutch oil.

I am an oil groupie, and have read a lot about oils.
Redline is an extremely good quality oil, but has
nothing functionally to distinguish it from Mobil-1,
which is also superlative. Of the fifty-or-so oil specs
and chemical analyses I've seen, those two are
the best overall, but the only major differences are
cost, and Porsche recommendation, both going to
Mobil-1. That's what I run.
Joe

 

Joe...

How about Motul??? I've heard lots of great things about them and a number of GT3 Cup cars use Motul even with the Mobil 1/Porsche relationship...I recently changed to Motul 0w-40 and I'm really happy. Not sure how to explain, but my car feels to be running better... The unreliable butt dyno!!!

Also...the last time I changed my oil, I did drain oil from the turbo...

 

Which Motul? Some are synthetic blends (with some mineral
stock), and some other Motul oils are full synthetics like Mobil-1.
Motul has a good
amount of total anti-oxidants, so it should resist acids for long
usage, like mobil-1, amsoil, and redline. Others I've seen do not
have as much.
Motul has slightly less zinc and phosphorus (anti-wear additives)
than Mobil-1, but not a huge difference.
Motul 300V sport is good at avoiding evaporative losses, like
mobil-1 (best) and amsoil.
Motul's retained viscosity over time is only OK, but so is Mobil-1's.
The best at this is Mobil-1's motorcycle oil or redline.

Besides brand, you should do your best to adhere to the
viscosity specified by Porsche. A thinner oil can actually
provide a small-but-measurable reduction in power loss,
but provides a thinner protective film.
Oil is also somewhat like underwear: It's better to use
Target underwear and change every day than to buy Gucci
shorts and change them once a week

Lastly, forget seat-of-pants. As far as oil is concerned, it is
completely placebo effect. We all know a freshly washed
car runs smoother...
Joe

 

hahaha... I love the analogy!

0w-40 is what my car came with from the factory and also what Porsche specifies along with 5w-40 in the manual. The Motul I'm using is 0w-40 Ester full synthetic and also is approved by Porsche...But I have thought about using a heavier weight oil since my car never sees temperatures below 60F. But some said the variocam system requires a lighter weight oil such as 0w-40...

Joe...any insight???

 

I say use the lightest viscosity recommended by the manufacturer
for the conditions. Light oil does circulate quicker. Also, oil breaks
down primarily due to heat, and this is independent of viscosity,
but thicker oil heats itself more due to greater shear forces, being
pushed through the same spaces, so it doesn't last as long.
Some manufacturers specify a somewhat thicker oil, to ensure
there is sufficient film strength even under the variations in
natural stock. Synthetics can usually be run a little thinner because
the manfactured stock is more uniform and stable.

 

I use Swepco 15-40.

 

cjv...

I'm not to knowledgeable in the area of oil and lubercants, but could you briefly explain why the change to a thicker viscosity oil??? I've read about lubercants in Bell's Turbo books...but i'm not sure what applies in the case of the TT...???

Thanks in advance!!!

 

I hope you have another dealer close by...

The factory service manual has the specifications for the oil (front differential, rear differential, and transmission use the same oil and I believe it is a gl4-gl5 synthetic (I'm on travel right now and didn't bring my service manuals with me <grin>).

If no one else replies to this thread with the actual specifications for the oil... I'll post them when I get home on Tuesday of next week.


Joe West

 

Hi Joe,

What were those oil specs (esp front diff type and capacity), thanks.

Bond

 

I hope your dealer is not Huntington Porsche, because if it is, I suggest you find a new dealer.

I wouldn't be surprised if Huntington Porsche filled a car with Koolaid instead of oil. The service manager, Bill, didn't even know that a 996 Twin Turbo has two turbos