trans fluid in the crankcase

can someone educate me on this? what does it do... and so on.

Are you talking about the idea of putting ATF in the crankcase to serve as an egine flush ? Bad Idea !

Is the trans fluid there on purpose? Found it mixed in? Running it only on it? Or using it like Marvel Mystery oil? Details, my man, it's all in the details.

Spinoff thread. Katy mentioned doing it to clean out sludge, here; http://grassrootsmotorsports.com/forum/off-topic-discussion/how-can-some-people-not-care-about-thier-car-rant/35385/page1/

Will wait for her to chime in, but I think that was intended as a flush for a motor with no load on it and a bunch of crud in the crankcase.

There are two very strong schools of thoughts on this: On a high mileage vehicle adding a cleaning fluid to the oil will get the crap out of it, clean up the oil galleries, and is good for it. Add, run for about an hour or so, then drain and put in new oil.

Other side says, by removing that crud, you will now open up, get rid of the "stuff" that is keeping the engine's seals from leaking.

About the only addative I'd add to the oil is Seafoam, as many on this forum have used it with good results. Quieted lifters, raised oil pressure....cleaned out junk in the engine. Haven't tried it, don't know first hand.

I think KATB's experience is a bit unique, in that the car was so beat to begin with, there was little to lose. That's her experience, and as the saying goes, your results may vary.

BUT, as a rule, I'd say, no. Not a good idea. If you want to clean out the interior, I think the majority would say, go with the Seafoam, and read the directions. Adding straight trans fluid to an engine with no existing problems is not a good idea. My 2 cents.

I've heard the same thing about adding seafoam to the oil, so far I've only done it via vacuum booster and the rest into the gas tank. This is pertinent to my interests.

i have used seafoam.. but when she said that i had just never heard of it before and was wondering about it.

Friend of mine added it to his gasoline, and it did clean up the crap in the fuel system to where it did make a surprising diference. Idling vs. not idling at stop lights.

WAY,WAY back in the day, I added a quart of "engine cleaning fluid" (it was probably kerosene) to the engine in my '67 Spitfire. Ran it for 20 min, then drained out all kinds of crap. That was in '76. So, take it as you will.

I do know of a few current posters whose lifters eiither became much quieter or no longer made any noise after a day of running Seaforam then chaning the oil.

I prefer to use a quality synthetic oil instead of messing about with de-gunkers. Synthetic oils have better/more detergents that the regular dino oil, I figure if you just use synthetic you don't have to worry about crud build up. Plus if you have an oil cooler, you would have to drain that seperately to ensure you have entirely removed the cleaning agent from the crankcase.

I have never done anything other than full rebuilds or regular additive free oil changes. Ever. I would really really really be scared of anything else.

My main fear would be of putting too much crap in the pan, where it could clog up the pickup screen. Often times, a gunky engine will stay running just fine for many miles.

Never had a problem using ATF as a flush.

It's just 5 or 10 weight oil with friction modifiers.

-disclaimer-

I've only ever used it in pre-1980s engines to free up ticking lifters.

Wait until you're a quart low, add a quart of ATF, drive to work for a week, drain and do a proper oil change.

On every engine I've used it on, it wouldn't have done any damage that wasn't done already.

Shawn

i dont trust seafoam in the crankcase.... also atf due to its additives is really good at keeping things suspended untill you drain it. thus any metal shavings in the motor (a motor run hard with 1 qt of oil in it is bound to have some from rings or cams) get suspended and removed before they cause harm. atleast thats the theory behind it. i know its always done a great job of cleaning things for me. even once used it through 3 time after time to clean a 1mz toyota motor that had enough sludge in it that you couldnt see the cams when you removed the valve cover. atf is also fantastic through a vaccum line to free stuck compression rings. (tho personally ill keep useing good old h20 for that stuff sounds crazy but try it) i dont tend to spend money on thinks like seafoam cause there are better things out there.

i used to have a can of GM engine crankcase cleaner around- it was a 1 quart steel can like oil used to come in back in the odlen days... i never used it and never had a spout to open it, but it always had an aroma around it that smelled suspiciously like Kerosene to me..

Before Seafoam and ATF there was Kerosene (the mechanics all purpose cleaner).

kerosene works well. im sure seafoam does too. but my dad told me atf so i stick to it. very few things he has said have proven to be wrong. he was just a shadetree mechanic but all his lil tricks ive used and they have all made my customers happy,

fastbmw wrote: Synthetic oils have better/more detergents that the regular dino oil, I figure if you just use synthetic you don't have to worry about crud build up.

That is a common myth. They actually have less "detergent." Their ability to dissolve more gunk comes from the fact that they have less stuff dissolved in the base oil to start with... The same reason distilled water will dissolve more salt than tap water.

The ATF thing doesn't hurt, but it doesn't really help either. Many think that ATF is a wonderful cleaner because of how long it stays red in a transmission and how clean transmission parts tend to be. But that's backwards... if it were so good at cleaning, it would get cruddy faster. ATF stays so nice and rosy red for so long because it doesn't have to deal with nearly as much as engine oil does. Engine oil gets constant high levels of blowby gasses, carbon from combustion, and water from combustion.

IMHO, the best thing to do is use a quart of Kerosene or Diesel fuel. Dump it in the crankcase, idle for 20 minutes. Don't blip the throttle, don't drive it, do not pass go or collect $200. You will have significantly reduced the viscosity of the oil and you don't want any additional pressure on the bearings than idle. Drain for a long time... like pull the plug and go watch an episode of Lost. If you have an external oil cooler, loosen the lines and let them drain as well.

Refill and drive. If you don't want to go with the extra draining, just keep an eagle eye on your oil pressure gauge and drive gently until its been up to temp a few times to evaporate any remaining solvent. I've done this probably a dozen times. I admit, I haven't done it on more exotic engines. I did it in the M20 in my E30, a couple LT1s, an LS1, and a couple other random aging vehicles.

... and oohhhh, the junk that came out of them

curtis73 wrote:

fastbmw wrote: Synthetic oils have better/more detergents that the regular dino oil, I figure if you just use synthetic you don't have to worry about crud build up.

That is a common myth. They actually have less "detergent." Their ability to dissolve more gunk comes from the fact that they have less stuff dissolved in the base oil to start with...

According to the Valvoline website

SynPower is designed with extra levels of detergent and antioxidant to provide outstanding deposit and heat protection. (answer #6 http://www.valvoline.com/faqs/motor-oil/full-synthetic-motor-oil/)

I don't know if that's true for all synthetic brands or not. But it seems like an uphill battle to determine what is true or not true when it comes to all motor oils. For all we know they are breeding dinosaurs in a lab and then grinding them up to make motor oil....

I've done the atf (Dexron) flushes in engines off and on over the years. Can't say I've ever observed anything impressive from them.

+1 for using ATF as an engine flush with good results. i've done it several times, but never on anything "new" (which in my book is anything less than 20 years old). IDK whether the valvetrain quieted down because the ATF cleaned up the crap inside the lifters and pushrods or because the ATF cleaned up the block passages that feed them. doesn't matter to me. what matters is that the valvetrain noise went away. i know a guy who used 2 qts kerosene and 2 qts Dexron2 and ran the engine at 3k rpm for about 30 minutes to "unstick the rings". that did not work, but it also didn't hurt the engine as far as we could tell. he went to jail a few months later, and was driving that car when arrested so it lived for at least those few months.

atf will unstick the oil rings..... it will not help with stuck compression rings.... not in the crankcase at all. .... best thing i know for that is marvel down spark plug holes. and let sit for a day or 2. then start motor and run water through intake the high expansion rate of the water when it evaporates will free the rings and destroy carbon buildup.

don't know if it's atf based or kerosene based.. but I've cleaned out old Suby engines .... quieted noisy lifters with NAPA branded block flush.... worked pretty well....

ATF can also be used to clean out diesel fuel systems. I wouldn't use it in the newer ones but I had a 95 Golf TD that I used it on and it helped.

The red dye is bad in a diesel because it resembles the dye they use in "off-road" or fram diesel. They occasionally swab tanks of commercial trucks, but I have never heard of them checking cars (at least up here).

ATF has litle or no detergents. So it doesn'f really clean. Running some really lite motor oil would work better. Back in the day when we didn't have the quality oils that we have today. Engines ould get noisy hydraulic lifters. I gave them the Bardahl treatment, worked every time. I had one that ran so bad that he thought he would have to have major engine work. Bardahl did the trick. So, if you want to clean your engine, use an engine flush.