1993 Audi UrS4 Heater Core “Quick”Replacement Method

After 29 years the stock heater core in my pearl '93 S4 finally started to leak. I credit this impressive lifespan to my regular coolant exchanges and my insistence on using the coolant with a distilled water mix. Rather than jumping into the replacement blindly, I of course turned to the FAQ at Quattroworld as I knew the replacement process had been pretty well documented over there. Here is a link to the instructional PDF I used: https://www.audiworld.com/forums/atta... Mahle / Behr Heater Core - https://www.autohausaz.com/pn/BH-4438... Audi OE Heater Control Valve - https://spareto.com/products/volkswag... Aftermarket Heater Control Valve - https://www.autohausaz.com/pn/4A0819809 Permatex Ultra Gray RTV - https://amzn.to/3nIxcgE If you don't want to silicone your heater box in, the part number for the OE foam gasket matches this inner door beam gasket - https://www.ecstuning.com/b-genuine-v... The billet aluminum cooling system parts shown were sourced from EFI Express. Thermostat housing - https://shop.efi-motorsport.com/colle... Coolant Flange at rear of engine - https://shop.efi-motorsport.com/colle... Billet coolant tee - https://shop.efi-motorsport.com/produ... Any other questions? Just let me know in the comments!