This FAQ will discuss all the various fluids that have been found to be superior for DSM's through experience and gleaned from research articles. Always be sure to review your warranty requirements before proceeding.
Everyone has their favorite brand of motor oil, as they do beer. It has been proven though, that synthetic oils are superior to conventional oils, especially for turbocharged engines. Synthetic's superior heat resistance is especially important. Use whatever brand suits you and your climate. Brands include Mobil 1, Valvoline synthetic, Castrol Syntec, Redline, Quaker State synthetic, Amsoil, and more. It has been recommended that new engines be broken in 5000 miles or more before synthetic oil is used to allow rings to seat.
The other half of the equation is that you must change your oil at least every 3000 miles or sooner under severe service. This is again, especially important for turbocharged motors to ensure long turbo life. These guidelines will insure the longest life for turbo and engine.
There are numerous engine oil treatments/additives on the market. The only two to have any backup data are Slick 50 from Petrolon and TX7 from Polydyne, both in Houston Texas. Slick 50 just released an SAE paper in which tests proved its' ability to reduce wear in rod bearings, cam lobes, cylinder walls, and rings. Polydyne TX7 has been proven by Ferrari mechanics on Ferrari Challenge 348TB's to add 15 Hp on the dyno. Petrolon can be contacted at 713-932-9954 and Polydyne at 713-694-3296. Read the data and decide for yourself.
DSM transmissions are very sensitive to lubricants, so the oil you use will have a direct effect on how the transmission shifts. Again, synthetics are superior to conventional oils. First, a GL-4 spec oil must be used in the transmission. Do not use a GL-5 spec oil or you will damage the synchros, the GL-5 additives are corrosive to the brass synchros. Three brands have been found to work best, Red Line MTL (or MT90, which fits DSM spec better), BG Synchroshift, and GM Synchromesh (not actually produced by General Motors). All have their followings. Some cars work better with one and some with another. It can be said with certainty that any of the 3 will improve shifting and transmission life dramatically over standard gear oil. This has been found at the factory too. If you suffer notching shifting and some gear grind, especially when cold, these products will help. If your transmission is notchy all the time and several gears grind, you may have to have synchros replaced or the transmission rebuilt. Depending on your car's age you may be eligible for repair at the dealer through some factory TSBs (Technical Service Bulletins) which replace the synchros with updated parts for a nominal deductable.
For AWD cars, GL-4 or GL-5 synthetic will work for the transfer case and rear end. Redline or any of the synthetic gear oils will work fine here. 75W90 seems to be recommended.
(TS: Note: I personally run MT90 in the tranny and transfer case (so 3 quarts just about perfectly fill the tranny and transfer) and Redline 75W85 gear oil for the rear diff. Redline recommends a mix of MTL/MT90 for DSM trannies, I think straight MT90 works better in warmer climates. The colder the climate, the higher percentage of MTL you'll probably want. People in really cold climates seem to have best luck with straight MTL.)
A 50/50 mix of a quality antifreeze and water is required for optimum cooling and protection. Coolant should be replaced at least every 2 years. Straight water is not recommended without some additive to protect from corrosion and lubricate the water pump.
One additive that has been proven effective is Red Line "Water Wetter". WaterWetter is a corrosion inhibitor and wetting agent that enhances the water's ability to conduct heat. It has been proven by Archer Racing on the Dyno to reduce cylinder head temperatures by up to 30 degrees on DSM motors (note this reduces CHTs, but probably won't reduce overall coolant temps). This lowers the chance of detonation and enhances power. It works best with straight water to a max of 30% antifreeze. It is not as effective as 50/50 coolant but still offers improved cooling. Use your judgement depending on your climate. (TS: Note: I use ~30% coolant and WaterWetter in California, but that is because it is easier to figure - roughly 1/2 gal of antifreeze, a full bottle of WaterWetter, and the rest water ;)
There is not much comprehensive data or articles on fuel additives for raising octane or cleaning injectors. Redline injector cleaner, Chevron Techron, and BG 44K are injector cleaners that are favorites and are claimed to be effective. Any cleaner should be labeled as a detergent to be safe for the fuel system. Additives such as 104 Octane Boost work but have a side effect of leaving deposits on plugs, valves and exhaust systems. For higher octane, unleaded racing gas is recommended.
Brake fluid is very important, and one of the most neglected fluids on a car. It has a tremendous affinity for water and will pull moisture in right through the rubber seals! Water-contaminated fluid will boil at a lower temperature creating gas. This will lead to spongy brakes and in the worse cases, no brakes at all! The brake system should be flushed at least once a year and semi-annually for more severe use. If you are racing, flush quarterly or after each event. Use a good quality fluid with the highest dry boiling point you can find. One of the most available and excellent brands is Ford heavy duty brake fluid available at your local Ford dealer.
The power steering on DSMs use Dexron fluid. This fluid should be changed regularly to enhance longevity of the system. There are synthetic transmission fluid available and they are recommended. An easy method of keeping the system fresh is to replace the fluid in the reservoir every oil change and the fluid will stay in good shape. Just suck out the fluid in the reservoir and replace. No bleeding or air contamination will occur and it is a 5 minute job.
Red Line Synthetic Oil Corporation
3450 Pacheco Blvd.
Martinez, CA 94553
(Free product brochure and technical info)
Petrolon Technologis Inc.
(Free copy of SAE paper on Slick 50)
Polydyne Performance Coatings
(TX7 Oil additive)