flushing engine with ATF?
 

my car is about to hit 100,000 miles and i'd like to do an engine flush to get any sludge out of there. i've heard you can use automatic transmission fluid to do this and it works great. has anyone here ever tried it? and if so whats the proper procedure? another forum says drain the oil, add in the transmission fluid, let it idle for about half an hour, drain the transmission fluid, put oil in and let it idle for 30 minutes, drain that oil, then put the oil in that you'll use for the next 3,000 miles. does anyone do anything different? thanks.

jon

Honestly if you have kept up on your oil changes and the car is running good now I wouldn't waste the money and time.

Or use one of the off the shelf products. I'm pretty sure they only use the trans fluid for the detergents.

If you are suspicious of sludge pop off a valve cover and take a look inside.

I'd let Curt chime in but you could also use seafoam.

ive seafoamed a car once. lotsa smoke !

but as for the ATF, ive accually never heard of using it as a flush agent. looks like ill be staying tuned

I have heard of it being used, I personally would not. I would go with the seaform 3 step cleaning

all this.

i'd never recommend an engine flush. what if there is junk? where is it going to flush to?

if it ain't broke....

Atf works to clean the engine. Its a detergent oil. BUT!!! I have only used it when there was a problem such as a noisy/sticking lifter. Have done it several times and has worked everytime.

As the saying goes, if it aint broke , don't fix it. If you have done regluar maintenience ie: frequent oil changes, there should be minimal sludge/build up inside engine.
Leave it alone. And be on your way.

P.S. One thing you should always flush your cooler, before installing rebuilt transmissions though.....:facepalm:

I have heard of using trans fluid to clean the engine, but I have never heard of replacing all of your oil with trans fluid. I was told to add one quart of trans fluid to your oil and run the car for 500 miles or so.

i heard it works great my uncle does it to his cars all the time i did it on my brothers old jeep it had over 300,000 miles and still ran strong

I remember being little and my dad leased a Jeep Grand Cherokee for my mom. That thing went 10,000+ between oil changes. Two days before the lease was up he drained the oil and mixed oil + ATF. The next day he drained it again and put in new oil. The dealer said it was one of the cleanest motors they've gotten back.
Just be careful cause sludge can end up places it doesn't belong.

Don't do it. Just change your oil regularly. Its best if you drain your oil when its hot or atleast warm so all the junk comes out. Besides that I agree if it aint broke dont fix it. You don't want any crap to get stuck in a oil passege and do more harm than good.

I wouldn't do it. The potential for damage is greater then the benefit, IMO. :nod:

Yeah, if the car has had synthetic oil I wouldn't mess with it. If it has 200K+ miles and buildup, then you don't have much to lose. In the non roller cam engines of the past, you could wipe out a lifter if you used a different brand of oil than what was used in the engine but nowadays it's not that big of a deal. Do the other routine maintenance stuff and you should be fine.