Toby Pennycuff

Pete,

Do you have any recommendations on oil for the G50 transmission found in an '89 Carrera? Are you still recommending the Kendall dino 75/95? This one has no LSD (I still have a case of the "smelly stuff"!). Would you lend your expertise here? Thanks Pete.

Toby

ricster

I'd use swepco 201

w00tPORSCHE

Kendall Super, three star 75w/90 would be Pete Z's answer. This is a synthetic gear oil & in his opinion the extra lubrication afforded by the synthetic oil helps the gear shifts throughout the temperature cycle. Now for the 915 gearbox he actually feels that all that lubrication is counter productive Due to the synchromesh design and would lead to premature wear. He recommends Kendall 3star 80w/90 dino oil for the 915. He also notes a high number of gearbox failures in the non-kendall dino users. I have swepco...mine has'nt failed yet

Toby Pennycuff

That's really the question..... Kendall dino versus Swepco 201. I run the Kendall in my race car and have run Swepco in my 930. It's about time to change oil in my (newish) '89 Targa, so I was looking for the expert opinion. Hope Pete will see this and chime in.

TBP

GTgears

Toby,
I'm not Pete but some consider me an expert.
The 901 in your racecar and the 930 in your 930 use Porsche's proprietary split ring synchronizers. These are the gearboxes that Pete, and myself, recommend you use a dino oil on.

Your '89 uses a gearbox made by Getrag that uses a more modern Borg-Warner style synchronizer. This is the reason that a synthetic oil is recommended. However, if the car isn't raced or tracked, you really aren't going to do any harm to it by using Swepco or any other dino oil. In fact, my wife and I run 201 in her Impreza, which is her daily driver and our sometime track toy.

The bottom line in my opinion is service interval. As long as you change your oil with a reasonable frequency, they will all protect your gearbox internals. Given the way that many of these cars are driven these days and that they are a 2nd,3rd or 4th car for people, the interval should be based on time and not mileage. Every couple of years for your street driven Sunday Porsche and every few races for your racecar and you'll do just fine.

Tango635

This is a recent thread where Mr. Z recommends Kendall Super Three Star 75w90, which is a synthetic:
http://forums.pelicanparts.com/porsc...-question.html

So yes, the 915 gearbox does better with the less slick stuff, dino oil, due to it's synchronizer design, while the G50 does better with with the synthetic.

You can read the long post for yourself, but my impression is that Pete recommends the Kendall wholeheartedly above even Swepco because of the years of good feedback and positive responses he has gotten from his customers. It seems he got a lot of responses like, "what you do, has never shifted like that before?" from a mere oil change. And that's the whole story about the Kendall recommendation, it's not that it protects better than Swepco or others, it's that it seems to provide slicker, easier shifting.

Your G50 doesn't have LSD, but if it did you would need to add the friction modifier that is sold separately. Kendall makes the dino oil for the Porsche designed GBs with or without the friction modifier mixed in.

Steve Weiner-Rennsport Systems

FWIW,......

We use Swepco in all of the Porsche transmissions: 901-915-930.

We use a good synthetic for best shift quality in all of the G-50's such as Mobil One Delvac. Redline makes a good product as well, and sometimes we mix two Redline products for effect.

Peter Zimmermann

Toby, just caught up to your thread. As others wrote, I believe strongly that Kendall synthetic 75w/90 is the best choice for your G 50. Kendall will provide smoother cold shifting than most other GL-5 oils, and from what I've seen in gearboxes that I've had apart, Kendall might also be able to provide superior protection for gear sets and bearings.

Toby Pennycuff

Thanks all. Got the info I need!

dshepp806

I've been sticking with the Delvac,..and changing yearly. I, too, go by time and not mileadge. I realize it's quite frequent, relative to Porsche's schedule, but I sleep better at night,..nice dreams of a healthy G50.

Best,

Doyle

Toby Pennycuff

Pete, one question as a follow-up..... Just got my CoA on the '89 Targa and it says that I have an LSD installed! Need to check because I really have not been in situations where one would realize that an LSD is present. So assuming I *do* have a factory LSD installed, AND I run the Kendall Super 3-Star synthetic, is there also an LSD additive for the synthetic (like there is for the dino oil for my 915)? Thanks my friend!

Toby

Amber Gramps

Marc, the new owner of Pete's Redline Services sold me a bottle of

-gm-performance-1052358-limited-slip-lubricant-additive.

Needless to say it completely changed the rear end of my car.

It stinks horrid bad. .

salukijac

The Kendall synthetic 75w/90 is one tough fluid to find in quarts. Anyone know of a supplier? Otherwise it'll probably be Mobil One Delvac for me.

Amber Gramps

Just for this I actually purchased a 2-1/2 gallon gas can and had Marc pump it out of what must have been a 55 gallon drum. The tranny still takes a while to warm up, but one once it's warm it is smoooooth. ...and ya, I can break the back end loose at will.

Peter Zimmermann

Yes, Toby, you will want to use LSD additive (the Kendall product is the same for dino or synthetic gear oil). If you can't find it locally pm me and I'll let you know where to get it!