Review on Mishimoto Performance Aluminum Radiator Transmission by Michael Thaxton

Like many if not most of you looking at this radiator, I pre swapped the radiator in my 99 M coupe because OEM units have been known to fail at around 90,000 miles. And probably, like most of you, I've given serious thought to a Zionsville Autosport radiator. Yes, it is a work of art and the price is the same. Somehow during my research I stumbled upon a Mishimoto aluminum heatsink, and hey, it looked pretty good on paper and it's a heck of a lot cheaper than Zionsville. It doesn't seem possible to install an aluminum spill tank, so I bought a new OEM unit as well. I'm not a mechanic so I took it to the dealer to have my favorite technician install it. Everything seemed fine and right as the service technician commented on what a beautiful radiator he had. And here the most interesting begins. This is not a simple replacement for the stock radiator, it is slightly thicker which requires modification which of course costs a lot of money if the job is done by a certified BMW technician. He eventually got in, but it wasn't nice on my credit card. Whether my engine runs cooler as advertised, who knows? I've never had problems with overheating. I've replaced the stock pump with a Stewart pump (which was leaking btw, but that's another story) at 60k, changed the coolant regularly, and it always works with an arrow right in the middle of the temp gauge. So who knows? What I do know is that I now have a slow leak that shows up as a bruise on the side of the radiator and a gradual drop in coolant level. I hope it's just a little play and not a bad weld. Just take a look. In general, this isn't the panacea I was hoping for. UPDATE: The leak turned out to be due to the use of a steel washer in the fitting, not a copper washer. Washing machine. Once this was changed there was no more leakage. After the fix there were no further problems. I have raised my rating from 3 to 4 stars.