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Cleaning Sludge out of a motor

Is there anything that you can mix with oil to clean the motor?

You’d probably get more information here if you gave more details. What kind of car is it? Why do you believe there’s sludge?

There is a commercial product called “Motor Flush” available at most autoparts stores. Adding a quart of mineral spirits or kerosene works pretty well too. Don’t drive the car with the oil diluted with these products…Let it idle for half an hour, gently revving it A LITTLE now and then, then change the oil. You may have to repeat several times. Add when the oil is warmed up and drain within an hour…

Here is some good info for you:

I have a 93 Chevrolet Suburban, We just put a oil pump on it. It had sludge in the oil pan.We cleaned the oil pan out good. You can run it the oil will go to top of the motor…But it dont drain back down like it should… But were buying a 97 Suburban but we dont like the oil they have been use in it…I need to know what we can use to clean most that oil out.Then change the brand of oil…I would like to know what to do for the 93 Sub. too. The 93 does have 240,000 miles on it…

Motor flush will do the trick for the 93 Suburban, but make sure you carefully read and follow the directions on the package.

Personally, I would not take the chance that motor flush, mineral spirits, or kerosene might eat away at the seals without first trying Mobil’s Drive Clean oil (on both cars), doing a couple oil changes in quick succession to try to get the sludge out. If that doesn’t work, then you might try some motor flush. I think Mobil Drive Clean oil comes in synthetic and non-synthetic varieties. I would use the non-synthetic variety. After the problem is solved, you should switch to a non-synthetic high mileage oil of any brand on the suburban.