Omg im about to pull my hair out, I havent been on here for a few Weeks cause I was able to borrow a car so I had a nice break. But now I have to return the BMW and get back to the 300. I cant even drive the Chrysler more than a few mins before it gets so hot im forced to pull over till it cools. I dont know what else to do. I replaced the coolant reservoir and some hose that apparently wasn't even attached. Its called crankcase something ( Sry, I dont remember what the name if it was at this moment) but either way I got the right one and it was pit on. Its still over heating. It could be so many things according to every 300m owner with this issue, ( thermostat, water pump, timing belt, maybe even spark igs according to one guys story, ) im so ready to burn the bitch. Down, lol. is there anyone out there that has had similar problems with a solution that actually worked?!? All I hear are stories about the same crap but not one person has said "oh ,hey this was my issue and this is what fixed it." Sorry bout the mis spells but my phone is stupid and wont let me go back and correct it if I dont catch it and fix it right away. im sure you understand what I meant to write.

 

well to hopefully help you out, I had this issues in a different model vehicle, Mine would only overheat driving down the freeway/HI way. It would operate perfect around town and anywhere I drove that I had sections where either I slowed down below 40 or stopped ( Like stop lights)
I tried changing water pump, Thermostat, checked timing finally found the radiator was just a little restricted so the flow was not enough to cool engine at HI way speeds.
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Dang just seen you last post was #11 I should of back read to be up to date on all info