I was out in my garage the other day talking to my neighbor, who's a mechanic at a transmission shop, and we got on the subject of engine buildup. He said a good way to flush an engine is to drain the oil, install a cheapie oil filter and then refill with the oil with about 1.5 quarts of ATF mixed into it, then run it for a few hundred miles... What?! Is that even safe for the engine? I can sort of see where he's coming from, with the detergent properties of ATF and all... but I'd imagine the weight and viscosities of the ATF and the 5W30 I normally use would be wildly different. Anyone tried this or have any input?

 

I have also heard this before but you only used ATF and only let it idle for about 5 min

 

I've heard that one before and I wouldn't do anything like that.

Is your motor really sludged up or something?

 

ive used it at a lube shop i use to work at when we where out of are oil flush

 

Never heard that....would personally never try it.

 

Isn't that why they make seafoam?

 

No, not really. We were just having a conversation and the subject came up. In fact, the bottom of the head, valve bottoms/faces, and piston tops are all clean as a whistle. When I had the head off while replacing my head gasket, I took that opportunity to carefully clean everything with carb cleaner, oven cleaner (fine on metal, just be careful you don't get it on anything rubber or plastic), an old toothbrush, a shop towel and my trusty thumbnail.

I have no idea what the bottom end looks like, but I'm about to find out when I change the oil pan gasket here in the next day or two.

 

they make engine flush and yes seafoam i heard works good. but atf i wouldnt trust that. it called automatic TRANSMISSION fluid for a reason

 

ATF is rich in detergents so its definitely useful in flushing out crud in your engine.. I've used it as a flush before. ran my engine for 30min before draining out the oil.

 

I dont know about 30 I guess depends but I was tought by my grandfather who was a mechanic. Fill like oil, run till hot and drain, Flush with cheap oil, drain and drain, fill with good quality oil. Its a very old school thing to do, and was normal years and years ago.

 

Im a Mechanic and Yes you can use ATF as a flush, but only put about 1 quart more or less and have the car idle for about 15-20mins then drain and replace filter and your good to go (: