Brake and transmission fluid recommendations please
 

Going to bleed my 997.1 brakes and change the manual tranny fluid soon.

Need recommendations for fluids please for DD street use. Wondering if over the counter stuff is better/cheaper than the stealership.

Cheers & TIA

For brake fluid, I use Castrol LMA synthetic. It's what my dealer sells, and can be had online for about $20/liter.

brakes:
ATE gold is fine

tranny:
Mobil 1 Mobilube PTX 75W-90
Mobil 1 Delvac 75W-90 is nice but prob not needed in street car.

If your looking for factory fill, I belived pentosin is factory brake fluid and porsche gear oil will keep your gears shifting more smoothly.

The power steering reservoir is marked Pentosin.

The Porsche Center in Stuttgart Zuffenhausen uses Shell Spirax S5 for manual transmission.

Regards,

CF

Regarding manual transmission fluid, here is what I collected after reading hundreds of posts on the subject (from Pelican Parts, 6 Speedonline, Rennlist, and Renntech). Perhaps more info than you want, but I spent ALOT of time researching this so I figure someone else can use it:

Porsche recommends using OEM: 999-917-546-00 oil which is fully synthetic 75W-90, but it is EXTREMELY expensive (>$40/Liter at Porsche dealers, but Sunset Porsche in Oregon will sell it to Rennlisters for ~$27/Liter).

There are less expensive alternatives which are just as good as OEM such as Shell Spirax S5 ATE 75W-90 and Mobilube PTX 75W-90 (both are Porsche approved), but these are difficult to find in the United States. Mobilube SHC 75W-90 is the factory fill from Porsche and is different from Mobil 1 Synthetic gear oil typically sold at local auto parts stores (also tough to find in the States). The replacement for the Mobilube SHC 75W-90 is Mobil Delvac 75W-90. According to the Lufteknic website, “The replacement for the Mobilube SHC 75W-90 gear lube, Delvac has been the market name used in the USA towards the semi/fleet maintenance market segment.”

Other transmission oil options include Motul Gear 300 75W-90, Fuchs Titan Sintopoid 75W-90 and Liqui-Moly GL-5 75W-90 (fully synthetic with GL-5 for the hypoid gears). Pelican Parts lists the Fuchs and Liqui-Moly under the OEM Porsche part number mentioned above. The Liqui-Moly comes highly recommended by the techs at Porsche Gearbox Specialists (G-Box) and California Motorsports Inc. – two recognized leaders in Porsche transmission rebuilds. Below is a chart I got online with some technical specs of these oils (please don't ask me what it all means).

I just replaced my gearbox oil yesterday and I went with the Liqui-Moly GL-5. It sells for around $17/Liter at Pelican. I bought 4 Liters and had about 2/3 left in the last bottle. If I had to do it again, I would have bought the OEM stuff, but I didn't know about the deal Sunset Porsche was running when I purchased it a couple months back. That said, I decided to use the OEM oil in my front differential (I have a C4S) since it only holds 1.5L.

As far as brake fluid, I use Pentosin Super DOT 4. I also just changed this yesterday. I bought 2 Liters (probably could have done the job with just one), but it's hard to tell when the new fluid is coming out since my old fluid was still pretty clean. Also, I flushed the clutch slave cylinder so I wanted extra fluid on hand. I would say I used about 1.2 Liters for the entire job (remember to bleed the OUTSIDE nipples on the calipers FIRST)

There are plenty of opinions out there regarding what types of fluids/oils to use in our P-cars. Others will chime in I'm sure. Hope this helps.

Sean

Sean, I'm curious why you say that the outside nipples should be done first. I'm also kind of curious which one is "outside" since they're both, you know, on the outside half of the caliper. I tend to think of them as upper and lower. But that's me.

As for the OP, if money isn't an object for you, I'd suggest that you just buy the OEM stuff from the dealer. That way you know you got the right stuff, it will work well with the leftover stuff in the system(s) and you'll have nice documentation for the next owner.

For brakes, ATE Gold, or Motul 5.1, or 600 (if you track) are great options.

For transmission, I'd stick to OEM. There has been many issues reported with non-OEM oil, either in cold starts, or when it warms up, that I wouldn't mess around with. I went through this process a couple of years ago as I had issues on track, and a fresh OEM fluid just fixed the problems.

I said bleed the outside nipples first because that is what is specifically written in the Porsche Workshop Manual. I know when I was searching the DIY threads, there was a lot of misinformation out there on which to bleed first. Since the OP said he was going to do it himself, I figured I'd save him the pain of wondering which one to bleed first.

I am not sure what you mean as far as upper and lower bleeder valves. We are talking about the 997 here. I have an "S" model so my brakes are the "Big Reds." Both bleeder valves (nipples) are at the same height. One is on the outside of the caliper, the other is on the inside of the caliper. I am not sure how else to explain it. Perhaps the standard Carreras have a different set up that I am not aware of. Others can chime in to clarify.

Sean

I am curious as to why no one is recommending the ATE Blue as I have two litres on the shelf that I was preparing to use for my next fluid exchange.

I believe the blue has been discontinued.

That's absolutely correct. The ATE Blue is no longer available in the States (probably due to some environmental reason). That's unfortunate because if you flush your brake fluid every two years like Porsche recommends, it's tough to tell the difference between the old and the new fluid unless you alternate colors. My brake fluid was about 2 years, 8 months old and was still a light amber color, just like the new stuff. I just ended up taking 300 ml out of the rears and 200 ml out of the front calipers.

That ATE Blue you have is like gold . . well it's blue, but it's like gold (ha ha).

Sean

Annoying environmentalists, always trying to make our air and water clean and our planet all nice and stuff.

Or maybe, just maybe... ATE blue is no longer available because of an antiquated DOT regulation stating that brake fluid must be clear colored that is only now being enforced.

I just use whatever the parts department manager at the local dealer shoves over the counter for brake fluid.

For the transmission I let the tech use what comes out of the dispensing nozzle/gun at the service bay or what the parts department orders from the warehouse.

The factory fluid may be a bit pricey but it has proved to be a very good fluid based on the fact my 02 Boxster's transmission has covered just over 280K miles and the transmission is working just as good today as it did the 1st day I bought the car.

BTW, I have to transmission fluid changed at the dealer. That stuff is stinky and messy to change. For the Boxster the labor is 0.3 hours. (The Turbo's labor time is a bit more but still very reasonable.)

And sometimes one can get a break on the fluid. Last time I had the Boxster's fluid changed the dealer had some left over transmission fluid from warranty work and sold me the fluid for $5/liter.

GTK, thanks!
Ah ha! Yes sir, you are correct! The last time I bled brakes was on my 996, and the nips were both on the outside, best I can recall. Or maybe it was the 993. Oy, I'm getting old.

I didn't keep my 997 long enough to bother with maintenance... :icon501:

The only downside to the blue is that it will stain the reservoir after a few years. Other than that, as noted, it is fine and in fact, preferable when flushing out old but still rather clean fluid.