Coolant System Flush?

[mrbowtieguy]

Is it OK to use a chemical flush solution in a 2004 GMCD Dmax such as prestone cleaner, or similar? It has 164000 miles and I don't know how long its been since its been changed. I'd drain the coolant first, then fill with disstilled water and cleaner solution and drive it a couple of hours and redrain and flush with fresh water. or should I simply flush and fill?

[Zembonez]

I'd think it would be quite safe to do. Those flushes are made for all vehicles and it isn't going to be there long enough to harm anything. At 164K I would certainly do it. It goes almost without saying that you would want to flush with water thoroughly before replacing the coolant.

[C & A s Dad]

I agree with Jim. I would suggest one of the milder flushes and not one of the HD formulas. Some of them can be pretty strong and should only be used in extreme cases. Prestone or Zerex make a regular formula that works great. If your water is not extremely hard with a lot of minerals, there is likely not reason to use distilled water. There are some who feel that distilled water can contribute to electrolysis. If you know you have very hard water, then I would use distilled water.

 

I am also a big fan of a product from Lubegard, called Kool it. We sell a ton of it and recommend it with every raditor or heater core replacement. It will completley eliminate all Chemical Electrolysis in your system.