I have an 02 deville that has been overheating and I have reasson to believe it might be the radiator I took it to a radiator shop to see if that was the problem the guy working touched the radiator and said that it was bad because it was cold he then told me that he couldent flush it because part of the radiator was plastic. I believe my radiator is clogged and wanted to have it flushed so I don't have to buy a new one . I can see that the sides of the radiator are plastic but does that mean it can't be flushed. How would I be sure that its my radiator that's bad.

I am chasing down the same problem with my car. The radiator is still cool when the engine is hot. I was going to try and flush the radiator myself but haven't found the time. Planning to take it to a shop maybe Thursday.

I'd check the thermostat first.

I changed it the other day. Tested both of them in a pot of boiling water, and they both were good.

I see no reason for not flushing it just because the side tanks are plastic.

I've never heard of that either. Try another shop!