Engine radiator OEM Volkswagen or OEM BMW

run a mk4 secondary rad.

I will will just add that I have a 2L 16V running no oil cooler and an early Mk1 radiator with built-in overflow tank, two pin thermostat, short 5th gear, and the car does fine in a traffic jam and with spirited driving.

90 16v Passat rad fit just fine in my mk1 Jetta with a single fan mk1 (which mounted to the rad just fine) you can cut the wires and set them up for how ever you like.

I had an older BMW myself (E36) and if you want reliability you'll need aftermarket (improved) radiator, radiator hoses and water pump.

Regarding our 1997 Jetta GLS that we've had since it was brand-new, I was topping off the original G11 with G12+ since about 2000, without any problems. A few years ago we had the radiator replaced, and the coolant was all changed out to G12 -- that is, the current G12.

plastic radiator ends tend to crack and leak on the 4.4's. make sure you get an aluminum upgrade.

I replaced the coolant tank, blue resevoir cap, thermostat, water pump and coolant but didn't help. Problem was my radiator was partially blocked. I replaced my radiator this spring and it's run like a champ.

VR6 Passat *works for an A3 radiator but will need modifications

I traded my mk8 GTI (early Canadian model) for a mk7.5R recently because my mk8 GTI was so problematic: the rad fell out at speed and left me stranded (this should no longer be an issue on these cars)