Reviews of OEM BMW engine radiator

OEM radiator. Replaced radiator on visit 5 (today). Bmw closed loop network is what eventually led to the radiator being checked as they’ve seen aftermarket radiators actually cool the cars too much, therefore sending the tstat fault in cold weather (this issue occurred first last winter for me, then again 5 times this winter.. all same fault code). Confidence that this is the root cause fix seems to be high so fingers crossed I won’t be updating this in a few days.

I've replaced a radiator on a BMW 2018 3 Series with as little as 22k miles. This particular vehicle was leaking from the side tank of the rad, where the plastic is crimped to the aluminum. Nothing abnormal could be seen, just the crimp failed.

BMW N51 engine, SULEV radiator, these cars came with a sensor that sticks to the side of the radiator for emissions compliance. Can't even get it aftermarket anymore (last time I checked) new radiator without the sensor is like $150, with the sensor is close to $800, and no you cannot use the old sensor, if you try sticking the old sensor to a new radiator it won't recognize it and it will trigger the check engine light.

The white tank has never been the issue for me, leaks are always in the radiator frame surrounding that tank. Somewhere at the bottom, probably where the lower hose goes. The plastic is brittle crap and it develops micro-fractures that become cracks over time.

I have a 2008 e90 335xi FBO with 197k miles and I am still on my original BMW radiator. If the stock original BMW stamped one works well... why experiment?

N54 335i - 200k miles radiator upgraded

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

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