Gentleman Driver

After much research on here and other sites, I cannot find a definitive answer to my question... Going to change the transaxle fluid while I am doing other work under the car next weekend and need to get the proper fluid for the job.

The only type I have seen recommended for non-LSD applications is the Red Line 75w90... but this is difficult to find locally. Any other suggestions that will be acceptable (may track the car twice a year, but mostly spirited driving, non daily driver) and easier to find?

Thanks in advance!

rob76turbo

You can find Royal Purple at Kwik Kar and Pep Boys. They sell a very high quality Synth 75w90.

PorscheDude1

I run royal purple in the engine and swepco in the trans.

Gentleman Driver

Having difficulty finding Swepco... the Royal Purple is available locally, but I have only read about the Red Line 75w90NS being the appropriate fluid. The Red Line oil states it "doesn't contain the friction modifiers for limited-slip hypoid differentials", whereas the Royal Purple states the opposite: "formulated with hypoid friction modifiers necessary for use in clutch or cone type differentials"

Will this make a difference in a non-LSD transaxle?

Both indicate being specified for GL-5 API use, which I understand is also important (I have no idea what any of this stuff means... )

again...

RajDatta

I use Mobil1 75W90. Can be found at any local parts store.
Raj

Jason Judd

What would be reccommended for the LSD type of diff?

Stephenwz968

I run the Mobil 1 as well.

Steve

SpeedBump

I use SWEPCO in both types.

FRporscheman

Whatever brand you get, just make sure the bottle indicates it is not formulated for LSD. It will either say it has LSD additives (don't buy it), or it'll say it has no LSD additives (buy it), or it will say nothing (in this case, look for other versions of the same brand that might say LSD on it, to be sure what's going on).

You want a 75w-90 as you know. Like Raj said you can find mobil 1 at almost any auto store. I run mobil in my '95 and I bought it at Kragen. I run Swepco 201 in my '93 and it was put in by a shop. I used to run Redline which I bought from a local NAPA. I believe most NAPAs carry redline.

The bottom line is, you can order anything and everything online so you shouldn't settle on what you can find locally. Choose what you want most and have it shipped.

Jason @ Paragon Products

If you do not have LSD, you'll want a gear oil that does not have a LSD additive. aka friction modifier. Red Line 75W90, Swepco and Mobil 1 will all have friction modifier. The Red Line 75W90NS does not have friction modifier so you'll get a little better synchro engagement. The LSD additive/friction modifier is just slippery stuff that allows the friction plates on clutch type LSD's to slip a bit on engagement so you don't get limited slip "chatter". Can you use a LSD type oil in a non LSD car, of course as many of you know. If you have a non LSD and you have a a choice, I'd choose an oil that does not have friction modifier.

SpeedBump

I found Swepco in the 968 without LSD when we bought it and have continued to use it. This will not harm anything will it?

Jason @ Paragon Products

No sir, the Swepco is a great product...very well respected in the Porsche community...plus it's made in Texas

FRporscheman

I beg to differ regarding the redline 75w90NS. True that it is labeled to not have friction modifiers, but it's the absolute wrong fluid for the 968 trans. I used it for a year and it was horrendously terrible. The gear engagement / synchro action went down the toilet and was very rough and uncomfortable. The correct redline fluid for non LSD 968s is MT90. I haven't used MT90 but 3 of my friends run it in their 968s and they all gave glowing reviews. I switched from 75w90NS to Mobil 1, and IIRC the mobil 1 bottle did not mention anything about friction modifiers so I assumed it had none. The synchro engagement improved when I did this switch.

My '93 has had swepco 201 in it for a long time, and it does not have LSD, and it feels like butter! It feels like an absolutely new tranny! Probably because it's been female-owned its entire life... but still - the swepco certainly isn't hurting.

Jason, if you have a street car without LSD, what do you use in it? And while I'm asking, what do you use in an LSD car?

Lemming

I run redline 75w90NS in my non-LSD 968 (daily driver) with no problems. For the track car, I mix redline 75w90NS and 75w90 (50/50) for quicker engagement (S2 tranny with LSD).

FRporscheman

Hmmm, then I stand partially corrected. 57w90ns sucks big time in my car. I forgot to say I also ran this in my 944 for a few months and it sucked just as bad as in my 968 so I switched that car to plain off the shelf valvoline 75w90.