Hello, I'm a new member. Has anyone ever heard of taking automatic transmission fluid and running it though the engine for a bit to clean the insides of the motor. This "Good Ol Boy" said he used this trick for years and it works great. Anybody ever tried it? Or heard of such a thing?

dylan1952

 

Yep.. thats old way of doing it.. with today oils you souldnt need to do this.. But if you think you need to..
1. Drain all the engine Oil.
2. fill to proper oil level with new tranny fiuld
3. start and run at only Idle( No revving at all)
4. run no more than 5 mins ( Unless it starts over heating.. STUT DOWN RIGHT AWAY!!)
5. Drain and replace oil filter and engine with with a good 5-30w or 10-40w engine oil..
6. Start and idle for 5 more mins and than your ready to go..

 

Madathlon has it right. We use to use this method on cars where the engine was really gummed and sludged up (the old Pennzoil was good for doing that). I wouldn't recommend doing it to a engine that's still in good condition. I always had a fear of having transmission fluid still in the engine. I don't believe you can get all the transmission fluid out by doing an oil change. As far as I know, transmission fluid does not have lubricating properties for the bearings and actually is corrosive. The only thing I'd add to Madathlon list is changing the filter again with the new old, just to make sure. Filters are cheap insurance. They have engine flush at parts stores, but I don't recommend that either. Theres too many rubber seals etc in an engine that sometimes don't agree and expand or swell with anything else but regular motor oil.

 

Hi Dylan & All,
I had a sticking lifter problem on a 4 cylinder engine in my escort a few months back. I also had concerns about running with xmission fluid, as it just sounded crazy. However, some research on the internet revealed that the transmission fluid has more detergent in it & some of my buddies with lots of automotive background swore by it. I drained a quart out of the engine, added a quart of automatic transmission fluid & ran it for 550 miles (I was on a road trip & couldn't change oil at 500 miles). After about 250/300 miles, I no longer had a sticking lifter. It worked great for me.
I thought about running longer than 550 miles, but was also concerned about loosening up too much crud, so I called it good. The oil that I drained looked like synthetic oil, it was soooooooo black. Hope this helps.
Regards,
Jon

 

Yes ATF is a cootie bob way of cleaning an engine. The big problem with trying to clean a sludged up engine like this is it may do too good a job! That is start loosening the sludge and soon a chunk plugs an oil passage or the filter resulting in a fried engine. If your engine is that sludged keep changing the oil and filter fequently until you have the $ and time to pull the engine apart and have the block and heads boiled out.
If you have just a small amount of sludge and/or varnish just use a high quality synthetic oil and filter and let the oil do the work over time.

PS: if your engine isn't sludged up it ain't broke, so don't try fixin it! There is no need to use any additives homebrewed or off the shelf if you change the oil regularly. Used oil should come out black, shows it's doing it's job!!!

 

Howdy,

I'm not convinced that one should use hydraulic fluids as engine oil. ATF/hydraulic fluids are VERY light and will exhibit very low oil pressures in a well worn engine.

I don't think you can say that it has more "detergent" than motor oils per se' Oil doesn't actually use "detergent" like we think. It's actually a dispersant.....meaning that it will suspend the solid contaminents so they can be picked up by the filter and/or be drained when the oil is changed. The older oils did not have dispersants like today and filters did not catch particles as small as they do today. With lighter oils you can design filters that catch smaller chunks! (There were bypass filters in the old days that worked great! and now too btw)

Hydraulic oils and ATF DO lubricate. It's the only lubrication in an automatic trans or a hydraulic pump/motor. They have to lubricate certain metal to metal contacts like brass/aluminum etc and they have to do at very high pressures (up to 4000 or more PSI)

For a pretty good discussion on oils and hydraulic fluids go here:

http://www.lubrizol.com/ReadyReference/DrivelineLubricants/14-atf/default.asp


Lubrication theory:

http://www.lubrizol.com/LubeTheory/theory.asp


By adding ATF to your oil you are just thinning it out. You can do that with other petroleum products. You could add diesel, kerosene, gasolene, ATF, hydraulic fluid, Marvel Mystery Oil (mostly Kerosene) etc.


Back in the "old" days radial aircraft engines had an oil thinning system for using just before shutdown in very cold climates. AV oil 100 and 120 (50wt and 60wt) are like grease at very cold temps. If you couldn't pre-heat the engine before starting you would use the thinning system.

This entailed allowing a small amount of avgas to be injected into the oil before shutdown. Presumably you would allow the engine to run for a short period of time after dumping in the gas to mix it into the oil throughly.

I don't remember the exact procedure but it seems you would look for a certain drop in oil pressure to decide if you put in enough gasoline.

If you didn't put in enough, it would evaporate before the engine cooled down and you'd be in the same boat the next morning!

If there was enough though you'd have thin oil at startup the next morning and after the engine warmed up completely all the gasoline would evaporate out.

I am not suggesting that anyone try this! With the oil breathers we have in old engines we would have a lot of gasolene vapor in the engine compartment that would be a REAL fire hazard!


You could probably get away with Diesel or Kerosene (which the oil flushers probably contain anyway)

I have flushed engines in the past by using light oil. Like 10W or 20W oil. but using a 5w-30 or 10w-30 or a 15w-40 oil does basically the same.

The oils now are pretty complex chemicals. They have very effective dispersants and don't require aftermarket additives (read "snake oils")

And they're mostly the same. Oil refiners don't usually make the additive packages in todays oils....companies like Lubrizol, Shell Chemical, Castrol, and others make the additives that go in ALL the retail oils on the market.
Buy any brand and you might be getting Base stocks from Quakerstate and additives from Lubrizol.

The best thing you can do is change the oil and filter frequently.

Several years ago Consumer reports found that oil in passenger cars driven daily can go about 6000 miles before changing oil and filter. The auto manufacturers are not in "cahoots" with the oil companies like some think....otherwise they would not be increasing the oil drain intervals. (VW reccommends 10,000 miles between oil changes in the VW TDI) Detroit Diesel had 100,000 mile oil change intervals on some trucks and the industry is talking about 2 oil changes over the lifetime of some cars in the future.

The only people who "want" to change your oil is the oil change people!!


What a long rant! My only point is that one should not use anecdotal or testamonial evidence (an oxymoran?) here. Just because someone uses "Whizbang Dino Slick" oil (or additive) and his truck doesn't burn oil does not mean that stuff prevents oil consumption! (remember the Slick 50 fiasco?...another snake oil!)


Just change it either every 5000 miles or less and every 6 months or so which ever comes first!


Ok ok ..I'll get to the original question. this has been said by many other people besides me.

If you have a very old engine, that ran most of it life with older non-"detergent" oil, and it's not had the oil changed frequently over it's life, and it has a LOT of sludge in it, you run the risk of dislodging some of that sludge during a thin (modern) oil/solvent flush and that stuff might not get picked up by the oil screen or filter.

This could plug critical oil passages like supply passages to main and rod bearings. This of course could cause you to spin a bearing causing catastophic damage. BOOM, CRUNCH, $$$$







Whew!



Cheers,


Rick

 

I'm with the rest of the guys here: Using ATF is the old way of cleaning out a cruddy engine, and I wouldn't recommend it for all of the reasons they cite, or at least I would never use ATF only in the crankcase.

I was about five, or thereabouts, when I first learned about that technique. Our old '57 Ford wagon had been giving us some trouble, and Dad was buying oil by the case for it. One night we stopped, for what reason I don't know, and Dad checked the oil. He came around to the back, opened the tailgate, and asked me to hand him a quart of oil. After telling him that there was only transmission fluid he decided I HAD to be wrong (after all, I was just a kid), he insisted I give him a can of "oil." The next thing I heard was "D***, it IS transmission fluid! Well, H***, I guess it'll just clean the engine out."

I think the car was using too much oil at the time for the one can of transmission fluid in the crankcase to be an issue. However, Dad was a bit more careful after that when he bought oil. Since the car had a standard transmission, we carried that case of ATF around until Dad found somebody that could use it.

 

Just food for thought

Had a Stang with a 351W, 90,000 miles and a loud lifter. addad a quart of ATF when I needed to add oil and the noise went away. changed the oil a day of driving later and drove it another 20,000 before selling it.

I have actually heard from old timers of running an engine on Kerosene, SCARY!!!

 

My Oh My, Alot of feedback on that question. Thanks everyone for their feedback If nothing else some interesting thoughts and stories. Thanks,dylan1952

 

My dad used trans fluid to clean the inside of the engine on a 66 T-Bird. It worked real well, it cleaned the pistons up so well, it started using oil. he commented a month later when tearing it down for a rebuild that he had never seen an engine so clean inside.

Moral to this story "If it's not broke don't fix it" unless you are prepaired to fix it.

 

One thing about this place, you ask a question and you'll probably get a lot more answers than you likely wanted to hear! There's a great deal of knowlege and experience floating around this place waiting to be shared. LOL!

 

I'll add my data point. I had a 400 V8 (non-Ford) that I let sit for about a year; it had about 140K miles behind it. When I tried to get it running, it ran very rough, did not want to idle, and backfired flames through the carb. It seemed to me that one or more valves were sticking. I heated a quart of ATF on the stove top, pulled both valve covers, and applied the ATF to the top of the head with a paint brush, using the whole quart. After I buttoned it up, if fired right off and ran great. I got it up to temp, drained the oil, and added new oil and a filter. Never ran better.

 

I remember, as a kid, seeing many people pour ATF into a slightly reved engine's carb to clean the valves etc...smoked the place up good but never seemed to hurt anything. I also remember an older man, back in the early sixties, filling his 58 buick's gas tank half full of kerosene and topping it off with gasoline. He did this on a regular basis.

 

a couple of quarts of diesel or kerosene in your oil(b4 u change it) will work good too

 

Like said above, the worst thing that can happen is that (kerosene, ATF, MMO, etc) will work and knock the stuff loose. My neighbor put a can of Motor Flush in his Grand Am, ran it an hour, then changed the oil. A week later it threw a rod or two on total loss of oil pressure. The screen was totally plugged.