flyguy

Heard something interesting today. I was told that about a week prior to an oil change if youre low on oil, it's ok to add a quart of ATF (auto tranny fluid) to the oil. The thinking behind it is that the detergents are stronger in the ATF and will clean out the system before the oil change.

Sounds kinda goofy to me, but I'm open to opinions.

any pros or cons to this?

-Ian

David Floyd

I have done the ATF trick, ran engine about 10 mins then change oil.

cpt_koolbeenz

ATF cleans out the engine and helps the seals expand... Only run the engine for about 15 minutes then drain it...

flyguy

why only 15 minutes... does that short period actually do anything? risks to running it longer?

Zero10

I ran with 2 litres of ATF in my oil for 4 months (Well 1 litre for 2 months, then another litre added as the oil got low). I had some very stuck lifters, it cleaned them up a lot, but they're far from perfect.

It's pretty much harmless.
The reason most people say 10-15 minutes is because they add it to a crankcase already full of oil, i.e. make it 1 litre over full. Harmless for that short of a time.

Like I said, I ran for 4 months, and have had no adverse effects what-so-ever. But I think 2 litres out of only 6 litres total is getting to be a lot, considering I only had 10-30 oil in there in the first place.

hosrom_951

YOU ADD ATF OIL IN ENGINE OIL???????????????????????? and RUN THE ENGINE??????????

theedge

Yes thats what weve been talking about...

UK952

I ran some gearbox oil in on an old mini I had that was so knackered it threw out a mist (smoke plus droplets) of standard engine oil ........... when i was a student and had no money. Never had an auto so don't know how standard gearbox oil and ATF differ.

Anyway I wouldn't put it in my Porsche engine.

If you want to clean out the engine I have heard diesel engine oil has a lot more detergents in than standard oil. If considering this I would go for a high quality one suitable for turbo diesel engines and be gentle on the boost until it was out.

Tony

PorscheDoc

I ran atf in for about 1000 miles to clean the lifters up a bit. Seemed to work, this is a pretty old school trick.

superjet.1

Yes it works quite well ive been a mechanic all my life when i worked for porsche we would put a half quart of atf in the new cars to quite lifter noise predominate to new cars. I wouldnt put more than a quart in at a time if your not gonna drain the oil it will make your seals swell ive seen it first hand.

hosrom_951

Wow, i never knew that. So just add 1 quart of ATF in your engine, let it dle for 15~20mins, then change oil.....hmmm...if they help clean out the lifters, then how many times would you do it? once every 20,000~30,000 miles ?

David Floyd

Some do this at every oil change

superjet.1

You can just remember only one quart at the most and dont leave in more than half a quart for and extended length of time.

Peckster

I have my doubts it does anything, I tried it once for noisy lifers and it did nothing.

Some people say it has more detergents. I wonder why that would be seeing as it's made to run in gear boxes where there's no combustion contamination.

I'll start using it as soon as a manufacturer recommends it or someone can produce a scientific study that proves it works in this application. Until then, it's just another mechanic-in-a-can solution.

flyguy

hehe... mechanic in a can...




yes... I'm really THAT bored