kkim

I try to do mine on a yearly basis. I drive about 15k miles/year.

I'm sure others will have differing opinions, though.

Edward

Hi Rob,

I tracked my car about 5-7 weekends/year on my daily driven 993 with annual miles of about 12K, and so I figured under such duress I'd change the tranny oil (Mobil1 75w/90) every year. Everytime I drained it, it was still kinda dark honey colored, at least some indication that it ain't "grimed up." Now that I've retired my 993 to pure commuter duty, I think I'll go every other year (prob about 20K miles total for that 2 years) before I replace the oil. I think that is prudent given it's use. That is still *much* more frequent than the factory recommends, but perhaps an expert will chime in.

Edward

amfp

I change my tranny oil with Mobil 1 75/90w every two years even with low miles. I just think is good and cheap preventative maintenance.

DesertBighorn

Patrick, just found your post, do you remember which version of Shockproof you used? Sent you a PM also.

Thanks,
Doug

trophy

I have been running Motul in my car for the past 5 or so years, it has been awesome for me. The car really is only a track car with approx 25-30 track days a year (so it is worked hard).....Very Happy...

Rick Lee

What kind of Redline is good for the Arizona climate?

matt777

When you guys say Mobil 1 are you talking Delvac?

I ran Amsoil 75W90 for a year and then the Redline. I can't say there was a noticeable performance difference. I think 2nd was a little notchier when cold with the Redline but that is about it.

Edward

Hmmm, talk about an old thread!

I just recently went to Redline. Not intentional, really. I have always used M1 since it's easy to get and cheap. But since my car was at my buddy's shop a short while ago, and I was due for a change, I figured why not as it was already on his lift ...and what he uses is Redline. I felt no difference whatsoever, FWIW.

Edward

Texas993

Mobil 1 Delvac is what is recommended by transmission guru Brian Copans and my shop, RUF Dallas. That is what I use on my recently upgraded/repaired transmission. Works well.

Pete Lech

I put in both Mobil One (not Delvac) and Motul around 30K miles and did not see any significant difference. Both were not quite as good as the Delvac factory fill, which we didn't know about then. I plan on trying the Delvac version again soon as I am approaching 60K miles.

One trick to reduce the second gear grinding when the car is first run: leave it in second gear when parked. You still have to shift a bit slowly at first, but it really does make a difference.

CaptainGSR

Newbie question: Is that Mobil 1 75w90 the silver bottle you can find anywhere (including pep boys and walmart)? Or are there different types?

Pete Lech

Found some interesting items on the Mobil One Site:

https://www.mobiloil.com/USA-English...ollection.aspx

mongrelcat

How/why does this work?

Interesting, so Delvac is not recommended for LSDs. I noticed something similar on the Motul site, they do not have a 75w90 gear oil for use with LSDs. Royal Purple makes no distinction. Not sure about Redline.

Texas993

Delvac is different. For most of us, it has to be ordered. Or some pcar dealers stock it as it is factory fill for the GT3.

Try to google it for a seller.

NC TRACKRAT

Mobil DELVAC 75W90...replaced SHC690...Available in 1 gal. tubs from Grainger Supply and www.Lufteknic.com. How often??? Different folks will give different answers. Time/mileage dependent.