Looking thru Robert Nitske's book on MBs, I see there is a 12 valve(M103 motor) and a 24 valve(M104) motor for the 300CE. Your post says 300CE so I'll assume you're talking about the single-cam(M103) motor and not the dual cam 24 valve M104 motor.
- Spark plugs - Bosch - Part H9DCO. There is also an H9DC, but the electrode is not as wide as the H9DCO. I've always believed the wider electorde carries current better. Who knows?
- Rotor-Cap - Numerous possiblities here. Look for German made parts...ie....Bosch, Beru.
- Fuel-Air-Oil filters. Look for Mann, Hengst; Mahle-Knecht - all OEM
- ATF - Dexron-III - pick any name brand.
- Power steering - MB part # 000-989-88-03/2 - Made by Febi-Bilstein.
- Brake Fluid - Use Dot-4 - Lots of possibilities here as far as brand - Castrol Dot-4 is widely available.
-Engine Oil - pick any name brand. Use the correct viscosity for your climate.
Axle Oil - I use 85W-140, but then I live in a very warm climate. If you live in a cold climate, 80W90 is likely a good choice.
- Coolant - use the MB brand or one of the extended use varieties. There have been all sorts of horror stories written about what will happen if you do not use MB coolant. I use the stuff, but do not believe the horror stories. What's important is to drain-froward/backward flush the engine annually and replace with 50/50 coolant/water. I prefer distilled water - no impurities.
If you're thinking about ordering parts, remember that this site sells everything you need.
1991 300-SEL - Model 126
M103 - SOHC
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