Engine Degunking With ATF

I'd mentioned it in my emissions test IBTL thread and touched on it a bit.

If you have an engine with gunky interior, sticking cam phasers, lifters that tick at random times, sticky rings causing oil burning, etc., use ATF with your oil. For severe cases use nothing but Dexron, but less drastic times call for 1/4-1/2 trans fluid with your oil change.

You don't put it in for ten minutes then drain it out. You put it in the crankcase and just drive the blessed thing.

I did an oil change on my Volvo that was setting camshaft phaser codes. The oil filter I took out at that time was unremarkable. This, however, is the oil filter I took out after 2,000mi with a 40/60 mix of Agip synthetic and Dexron VI:

The cam phaser code had mostly gone away, but started coming back again. Most likely because the filter was just that clogged I did the oil change with another 40/60 mix of oil and ATF and I'll pull it out after another 1500-2000mi. So far, the phaser codes have disappeared again with the new filter.

Any chance of harm from the much lower viscosity of the atf/oil mix?

ATF is apparently 5W20 in viscosity, so no.

I had pure ATF for three thousand miles in my 1.8 Golf, which the internet will tell you requires 20W50.

If you do this, I'd strongly recommend using it in conjunction with a diesel rated oil, stuff is designed to be 5-10% soot and still lubricate fine. Also has a much stronger additive package to compensate for being thinned out with a lubricant not designed for engine use. Speaking of which, I'm told 1/2-1 qt of diesel fuel in the crankcase gives similar results.

This.is relevant.to my interests. I have an engine that's all.sludged to hell and I was just trying to figure out how I was going to fix that.

It is used very commonly in the rotary world to bring "dead" engines back to life after filling with ATF and a nice tow behind a truck with said car in gear.

JtspellS wrote: It is used very commonly in the rotary world to bring "dead" engines back to life after filling with ATF and a nice tow behind a truck with said car in gear.

That's something different altogether. That is when you have an engine that isn't mechanically bad, just stuck with carbon, so you pickle the combustion chambers of engine for a few months in trans fluid.

I remember one of the Mazspeed guys talking about it in the late 90s as a way to use engines that were sitting in junkyards for years, when scoring cheap engines to run in Spec7/Pro7.

In reply to Knurled:

Idk about completely different, but it just goes to show it will clean just about anything given enough time.

I also have done this in a few of our fleet trucks (4.2 F 150s) that we got from the auction with positive results, biggest thing is like op suggested at was change the filters often while running it.

I was taught this trick back in my junkyard swap and drop days. I have witnessed near miraculous results from dumping a capful in each spark plug hole, turning over by hand, then firing up, and letting the smoke roll. Of course, our one and only goal was to get on the other side of our remarkable 30 day warranty period. I also knew people who would run 100% ATF in the crankcase to no obvious detriment.

So, in a newer ford product that uses 5W20 from the factory, would it be advisable to fill it with straight ATF?

In reply to JtspellS:

Sorry, it's a pet peeve of mine. Some people have this idea that they can glug some ATF down the carb overnight or even in a running engine and that somehow it makes a difference. Anything you might notice from that, you'd also notice from upping the amount of premix that you use. I've found compression gains from going as rich as 50:1 fuel:oil.

In reply to Bumboclaat:

I wouldn't, just because the additive packages are different. Trans fluid doesn't have to work with combustion byproducts, so it's not really equipped to deal with them. That's pretty much the only reason why I say to put at least half engine oil in. I know that I say that I've done a 100% fill, but I didn't have much to lose.

Knurled wrote: I know that I say that I've done a 100% fill, but I didn't have much to lose.

yep.

I've done this in the past with an old Geo Tracker. Filled the crankcase with 100% ATF and let it ideal for 30 mins then drove it gently fold 5-10 miles before changing. I swear it made a massive difference.

But if you head over to Bob is the oil guy, they will tell toye over there that ATF has less detergents than modern oils andits a waste of time. People over there know there stuff, but my mileage did vary.

The things you learn in this place.

Adrian_Thompson wrote: But if you head over to Bob is the oil guy, they will tell toye over there that ATF has less detergents than modern oils andits a waste of time. People over there know there stuff, but my mileage did vary.

My counter to that is, if the engine oil's higher level of detergents made a difference, that carboning/sludging wouldn't be happening in the first place, would it?

Maybe it's not the quantity but the type that matters. Or maybe it's a lack of additives that makes a difference - the junk is breaking free but not dissolving/staying in suspension. I note that, in this case, the oil still looked goldish-pink clean on the dipstick (it did pour out black). In addition, everything that I found in the filter had to go through the oil pickup screen and the oil pump, so the junk was necessarily small enough to go through there, but still wasn't being absorbed by the oil. Maybe that is the key, it isn't being absorbed in the oil and then falling out of suspension in the low flow/cooler sections of the engine.

Theorizing about why it shouldn't work is all well and good, but this engine makes three for three on the list of engines that ATF in the oil has helped for me.

I'll have to try this with my new Miata engine. I took the valve cover off yesterday and it looks muuuuuch dirtier than the engine that came out despite having less miles.

If the engine's already out of the car, then I'd simply invest in a whole lot of carb cleaner and do the job "properly".

My 1.8 Golf was an interesting case. Bought it from a longtime customer. Service history involved a lot of attempts to solve the noisy lifters. Jumping around in oil brands (Mobil, Redline, Amsoil, Royal Purple) mainly but also the oil pump and pickup were replaced. Nothing ever worked well enough. I drove it for a bit and then one oil change decided to go for broke and run pure ATF in it. I had a Corrado G60 engine on a stand so I figured if I hurt it, no big loss, and if it made no difference, the ATF was still cheaper than the Mobil 1 that I'd been feeding it. The lifters shut up and stayed shut up for another ~50k miles before I sold the car.

The Quantum wasn't so much noisy lifters as it was fogging for mosquitoes with its mutant oil-burning skills. Skills that cleared up by putting in a quart of ATF for every two or three quarts of oil added. (Well, mostly. Nothing will help worn valve guides or head gaskets that leak oil)

In reply to Adrian_Thompson:

I'm of the opinion that it's gotta be the seal conditioners, friction modifiers, or something to that effect. Or perhaps just a lower quality base stock with a lot of light HCs in it, that gives ATF that inexplicable cleaning power. In any event, a little bit of something with some actual solvency, like diesel fuel, should give equal or better results and be a lot safer than diluting engine oil additive packages to a higher degree with multiple quarts of ATF.

I think the cleanest used engine I've ever seen inside the valve cover of, in person or in pictures, is a friends Yanmar marine diesel in a sailboat that rarely gets run for longer than 20 minutes at a time. It was also missing a thermostat until recently, and as such tended to end up with somewhat diluted oil. You could eat off the valve cover in that thing, and it's one dirty running mofo, even by 70s diesel standards.

I've done the ATF degunk a couple of times, most recently on Ugly as documented here: http://grassrootsmotorsports.com/forum/build-projects-and-project-cars/the-ugly-e30/50113/page4/

IMO, it helps, but I'd only use it on older, neglected engines. On my newer cars that I've been maintaining with regular oil changes, it should never be necessary.

I put in 1qt of ATF 500-1000miles before an oil change. Keeps my engine & oil pretty clean. Really mitigates the carbon buildup on the rings Saturns are so well known for. 150k miles and it still burns very little oil.

Has anyone had success with ATF resolving the infamous BMW Vanos issues?

ATF has a lower temperature rating than crankcase oil so hot weather or towing your race car is not a time to be trying this.

In reply to nderwater:

Correct me if I'm wrong but that's more of an o ring issue causing noise right?

I wonder if Honda motorcycle hydraulic timing chain adjusters would benefit from this. They start not adjusting so well and certain oil changes have been known to fix or improve this. I would think just letting the bike idle for 20 minutes would be enough and I wouldn't want to run the thing on the street.

That said I've had the adjusters making noise now and then for a good 30,000 miles and nothing actually happens beyond an annoying noise so I'll probably just let this go.