Kyle

Hi how are you? I flushed my radiator out and put valvoline
coolant in due to having really dirty water in it (just bought
recently) and I haven't had a problem, but after I drove for a
while a bit of sludge would come to the top so I have
drained and filled with more expensive coolant and since I
have done that it overheats and chugs/splutters at low
speed/idle, so I replaced the thermostat and put more of
the expensive coolant in and it still overheating and running
like crap.
So in short, since I've put the dearer coolant in I've had
nothing but problems, but with the cheaper coolant it was
fine. The dearer ones contain ethylene glycol and the
cheaper one doesn't, would that matter????
Thanks for your time
I'd appreciate any feedback thank you