Fluid Questions
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Fluid Questions
Hey everyone, got a few question about fluids. According to the manual for my 1984 928S US/Auto, it said the engine oil to use should be an API Service SE or SF and 20w50, 15w40 or 15w50 multi-grade.
I found a synthetic blend 20w50 however, the API service is listed as SJ/CF? Is this good to use in the Porsche cause I seem to be having problems finding SE or SF.
Brake Fluid in the manual is listed as SAE J1703 DOT 3 or 4. I found some brake fluids that is DOT 4 but didn't see any SAE numbers. Will this work?
ATF said it's a Dexron thing. I found a synthetic Dexron III ATF. I hear Synthetic is better but you can't go back to regular after switching to synthetic. Will I notice a difference using synthetic?
Last question now, power steering fluid. I hear you can use the Dexron ATF fluid for it also. I found a name brand power steering fluid but it said it's power steering fluid with sealer. Will this sealer thing hurt my power steering? The maintenance list I had posted before said I may have leaking in the power steering rack although I didn't notice any myself. Is it possible this fluid with sealer might even help the rack? (I may eventually end up getting a rebuilt rack but not the main concern atm)
Any thoughts/suggestions on these questions are greatly appreciated. Thanks.
I found a synthetic blend 20w50 however, the API service is listed as SJ/CF? Is this good to use in the Porsche cause I seem to be having problems finding SE or SF.
Brake Fluid in the manual is listed as SAE J1703 DOT 3 or 4. I found some brake fluids that is DOT 4 but didn't see any SAE numbers. Will this work?
ATF said it's a Dexron thing. I found a synthetic Dexron III ATF. I hear Synthetic is better but you can't go back to regular after switching to synthetic. Will I notice a difference using synthetic?
Last question now, power steering fluid. I hear you can use the Dexron ATF fluid for it also. I found a name brand power steering fluid but it said it's power steering fluid with sealer. Will this sealer thing hurt my power steering? The maintenance list I had posted before said I may have leaking in the power steering rack although I didn't notice any myself. Is it possible this fluid with sealer might even help the rack? (I may eventually end up getting a rebuilt rack but not the main concern atm)
Any thoughts/suggestions on these questions are greatly appreciated. Thanks.
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From: Ball Ground, GA
The current API (American Petroleum Institute) ratings started way back when with "SA", and as the oil specs have been changed (I used to say "upgraded", but I'm not so sure of that anymore), it gets a new letter. Any oil with an API rating that is higher than the one specified for your engine is fine.
SAE J1703 is the SAE (Society of Automotive Engineers) standard that tells how to rate brake fluids. You should find J1703 somewhere on the can of any good brake fluid. The differences in the DOT (Department of Transportation - US government body) are usually in temp ratings and moisture degradation, with a higher number being better - EXCEPT, that is, for DOT 5. DOT 5 brake fluid is silicone based, rather than the usual glycol based. While silicone appears to have some performance advantages, it does not really work well in most cars, and very, very few people recommend its usage. Just to complicate things, there is now DOT 5.1 fluid available. This is a high-performance glycol based fluid, and should work well in the 928.
You can get synthetic DOT 3 and DOT 4 brake fluids - should work fine, but I would go for DOT 4 or DOT 5.1 fluid.
The transmission uses Dextron. Dextron III is pretty much all that is available now, and should work fine. Synthetic is available, and should work fine, but costs more. I seriously doubt that you could tell any difference with the synthetic.
Be certain that you know how to check the trans mission fluid correctly - it isn't obvious. Go to
http://www.nichols.nu/tips.htm - lots of good tips there.
The power steering system uses Dextron ATF - NOT power steering fluid. The most common place for leaks is just below the reservoir - the hose ends get soft. You can sometimes cut off and reclamp the low-pressure hose to stop a leak. I would not use a "stop-leak" fluid in the rack except as a desperate last effort to get one home from a trip.
SAE J1703 is the SAE (Society of Automotive Engineers) standard that tells how to rate brake fluids. You should find J1703 somewhere on the can of any good brake fluid. The differences in the DOT (Department of Transportation - US government body) are usually in temp ratings and moisture degradation, with a higher number being better - EXCEPT, that is, for DOT 5. DOT 5 brake fluid is silicone based, rather than the usual glycol based. While silicone appears to have some performance advantages, it does not really work well in most cars, and very, very few people recommend its usage. Just to complicate things, there is now DOT 5.1 fluid available. This is a high-performance glycol based fluid, and should work well in the 928.
You can get synthetic DOT 3 and DOT 4 brake fluids - should work fine, but I would go for DOT 4 or DOT 5.1 fluid.
The transmission uses Dextron. Dextron III is pretty much all that is available now, and should work fine. Synthetic is available, and should work fine, but costs more. I seriously doubt that you could tell any difference with the synthetic.
Be certain that you know how to check the trans mission fluid correctly - it isn't obvious. Go to
http://www.nichols.nu/tips.htm - lots of good tips there.
The power steering system uses Dextron ATF - NOT power steering fluid. The most common place for leaks is just below the reservoir - the hose ends get soft. You can sometimes cut off and reclamp the low-pressure hose to stop a leak. I would not use a "stop-leak" fluid in the rack except as a desperate last effort to get one home from a trip.