This article is from the Watercooled VWs General FAQ, by Jan Vandenbrande with numerous contributions by others.
A: Here are a couple of one liners, some of which are explained in more
detail elsewhere?
- Check fluids often (oil, coolant, PS fluid, brake fluid, battery)
- Follow recommended maintenance
Change oil & filter 3000 miles/5000km or 7500mi/12000km with synthetic oil
Use the correct weight of oil for the climat
Change coolant when it looks dirty (or every 2-4 years) and use phophate
free coolant mixed with distilled water
Bleed brakes yearly. Use Dot 3/4, Dot 4 or Super Dot 4 fluid
Change fuel filter (at least every 30k miles or 50k km)
- Use OEM, MANN or Bosch filters.
- Change the oxy-sensor at the recommended interval (if you don't
you may burn your cat. converter which is A LOT more expensive to replace)
- Reset mechanical trip odometers when the car is stationary
- Warm up your car by driving gently until your oil temp is 80C
- Check your CV boots for breaks often and replace as soon as they crack
(this will prevent having to replace the whole joint)
- Use fuel injector cleaner every couple months
- Check tire pressures periodically. It's better to over inflate than to
underinflate (I run 40 psi on my G60 with little effect on wear)
- Garage the car, leave it out of the sun
- Replace all gaskets and seals if you take something appart.
It's a small cost in comparison to the cost and time to take
something appart
- Cars with solid lifters: Adjust valve clearances as recommended
(if you don't, you may burn your valves).
- Replace all belts every ~60k miles/100k kms
- Replace all hoses every ~100k miles/160k kms
- Replace vacuum hoses as they get stiff and brittle
- Learn how to rev-shift to save clutch wear
- Check transmission level periodically. Familiarize yourself
first what that level should be for you car.
- Stay away from low quality parts, especially for CVJoints and axles
Do not use remanufactured parts, only OEM
- Run your AC at least once a month for a couple of minutes
to lubricate the bearings and prevent the seals from drying out
 
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