Volkswagen Thermostat
Volkswagen and Audi switched to plastic thermostat housings on most V6 models around model year 2000, replacing the earlier aluminum design. We have found these plastic housings tend to leak after a thermostat replacement rather than on their own.
- Replacing a thermostat is common practice during a timing belt service, since thermostats can malfunction and the timing belt must be removed first. When replacing the thermostat, we recommend also replacing the housing.
- A new plastic housing is a reasonable option and should last as long as the thermostat itself. For turbo or high-performance applications, upgrading back to an aluminum housing costs about $70 more.
- The aluminum housing offers greater durability and can give added peace of mind for drivers who want a longer-lasting solution.
Volkswagen and Audi plastic thermostat housings, used on most V6 models from around 2000 onward, tend to leak after a thermostat has been replaced rather than on their own. The replacement process requires removing the timing belt first, and disturbing the housing during this procedure is often what causes leaks to develop.
Replacing VW Thermostat Housing – Volkswagen Repair Denver
Volkswagen and Audi starting using plastic thermostat housings on most of their V6 cars around model year 2000. Earlier model years used an aluminum housing. We have not seen a lot of the later plastic housings leak if they are not disturbed. We have seen them leak after a thermostat has been replaced. Replacing a thermostat on one of these vehicles is common practice when a timing belt is done, because it is not uncommon for thermostats to malfunction and replacing one involves removing the timing belt first.
If you replace the thermostat it is a good idea to also replace the thermostat housing. A new plastic housing is a reasonable replacement and should last the life of the thermostat. For high performance, turbo applications or customers just looking for a little peace of mind backdating to the more durable aluminum housing for about $70 more is a good choice.