I owned a 93 Ford (Pre-PSD) 7.3 that I bought used with 273,000 miles on it, that the previous owner ran ATF in every tank, and it seemed to do pretty well. It had never had new injectors or had the valve covers off. I bought this truck cheap and resold it to make some $$$ on it, but put 10K on it in the meantime and it ran like a top.

As for ATF not being a good lubricant, I beg to differ. I mean, it is what protects the gears in all of our automatic transmissions and whatnot. I am sure it does add lubricity properties to diesel fuel.

I doubt ATF ran through the fuel tank would hurt the injectors at all at that kind of dilution, and should help to lube them and keep the functioning properly.

that said, the major problem with adding ATF to fuel regularly is that it leaves a lot of ash when burned, that leaves residue in the combustion chamber, on the piston rings, and valves. That is kind of against the idea of it cleaning anything out. ATF has little in the way of detergency--it does contain dispersants which will do little in the fuel combustion process.

I don't advise the use nor use ATF in my fuel in any of my diesel engines, be it my Cummins, TDI, tractors, etc. I also would hesitate mightily before filling my fuel filter with it on a HPCR engine. But to run it through the fuel tank occasionally, even on a HPCR engine, would likely do very little harm, and the ash it did leave would be long gone prior to the next usage of ATF.

As for engine oil through the fuel tank--a lot of fleets burn off the used engine oil by mixing it in their fuel. I believe there is a maximum allowed percentage, but it is done, and with very little negative consequences. It too will help lube the fuel, and when mixed with fuel, doesn't really add all that much in the way of contaminants or debris. On big rigs, this used oil most likely has been passed through bypass filters anyways, so there isn't anything left in the oil large enough for your fuel filter to catch--which wouldn't plug it any faster than normal. Do I do it? No, and I won't. But will it kill these fuel systems in small quantities? I highly doubt it. We probably run worse junk through ours everyday and don't even realize it.

 

so by the original rationale, none of you will ever take your cummins to the dealership to have any service done.

...at Reno Dodge, it is standard practice, done by each of the 25+ techs there, to IN FACT fill new fuel filters with ATF every time they change it.


so..... even though we can thank Luke S for creating this thread, playing devils advocate and questioning the method, i can guarantee each and every one of you who read this thread, that we would have a VERY large amount of factual evidence supporting the fact that it is a BAD practice, if it actually was.

unfortunately, this is not the case. please, somebody show us EVEN ONE factual incident where mixing ATF with diesel has actually had a detrimental effect on your truck.... waiting...


this excludes friends of friends etc stories. i want to see pictures, or even one diagnosis of fuel system failure or internal damage caused by running ATF through a truck!!

 

Why is it Beagle1 always seems to find his way into most threads, even if it's by mentioning his occupation??

 

That is hard for me to believe. If you didn't know this all ready my family owns two new car dealerships, one of which is a Dodge-Chrysler-Jeep store, that I am a manager at. I can assure you, if Dodge and Cummins knew that Reno Dodge was pouring ATF into the fuel filters on HPCR engines somebody's head would be rolling at Reno Dodge. Let me get in touch with one of my factory contacts at Dodge and Cummins and get back to you with an official statement on pouring ATF into a HPCR engine.

 

I would like to hear what Cummins has to say about it too. I still think there will be no issue with it on 12v and 24v but I don't know about the HPCR.

In the end the best way to prime the filter would be to throw some fresh diesel in the filter.

 

I have made contact with Cummins and will be posting their official response once I get it. I agree with the second statement in you last post 100%.

 

With the 3 Gens., you don't have to "pour" anything in the filter bowl, to prime it. Just turn the key to the "on" position for 20-30 seconds, turn it off & then repeat this proceedure.

The fuel pump primes the filter bowl. This way, you don't have a chance of introducing any unfiltered "product" into the HPCR.

Joe F.(Buffalo)

 

Buffalo, thanks for saying that. With all this discussion I forgot to even mention that. You wouldn't need to "prime" with anything as it does that for itself.

 

I use to be a 1st generation, 1993 W250.Auto trans fliud was discussed on that forum back when and if I remember correctly was frowned upon then.Auto trans fliud has propertys in it designed for clutch matierial to grab and lock and also for lock up torque convertor material etc.It was mentioned how ATF would score and cause undo wear on injector interials etc.Maybe eons ago on BIG RIGS with large injectors with big bores and nozzels it was used with no harm,I don't know.But I never would have used it in my 93 W250 or any other small diesel.I also think this has been hashed out on BOB THE OIL GUY FORUM also.

 

Thanks Hounddog. You mentioned some things about ATF that I failed to think about. I am with you, I have two first gens and a third gen, and I wouldn't even run it through my 300,000 mile first gen. People talk about dooing it on old Detroit's and old 70's, 80's and even early 90's model diesel engines. But you are comparing apple's to oranges as far as I am concerned. This new HPCR fuel system will not take the crap we used to throw at those older engine's. Somebody says they ran there Ford 7.3 Non-turbo IDI for 200 and some odd thousand miles with it, big deal, that is like comparing a Dodge dynasty to a Chrysler 300C. I just don't get it? If you want to clean your injector's, why not use fuel injector cleaner? All the millions of $$$'s these addidtive companies spend on engineering things to do the job right, and then sell it for the same price or less than a jar of ATF, and we pour in ATF?

 

I am going to bow out of this discussion until I recieve an official statement from my contacts at Cummins to share with you guys. If it seems like I am angry about this I am not. I tell customers our position on these kinds of things everyday, but then I follow that up with "it is your truck and you can do whatever you want with it, I am not going to stop you, but this is what we as a dealer recomend". I just really hate to see some poor guy or kid who may be financed up to his eyeballs on one of these trucks pour in something that was not designed to be run through a HPCR fuel system. If he has fuel system problems and tries to get us to fix it under warranty, it may turn to a problem real quick. If we need some injectors, we don't just order injectors. They are a restricted part. Gotta call up the good old star hotline. We say, "hey we need some injectors", they say "do you see any signs of fuel contamination or tampering with the fuel system". That is their first question. Then we have to send the old one's back to them to examine. If they find traces of ATF in there, I can guarantee they will say "sorry, fuel contamination, this'll be customer pay". They don't give a dang what some diesel mechanic from the 70's said. Now maybe some of you guys can cough up the money to buy a new fuel rail or fuel injectors. But I'd guess there are more then a couple guys out there who might lose their truck if the had to cough up $3000 or so $$$'s on a non-warrantied repair?

Am I making any sense at all?????

 

ATF if I'm not mistaken has traces of zinc/calcium and some other items that are not as slick(some propertys in it are made to grab/hold and react to certain metals used in a auto trans) as one might believe.It also is not designed to withstand heat like motor oil or hold stuff in suspision.The reason the insides of a auto trans stays so clean is because nothing is introduced into it.Its a sealed system with no combustion after affects etc.All MODERN motor oils clean better then ATF.Decades back this was NOT the case.Lots of cleaners and lubes out there that do a MUCH better job then ATF for cleaning and lubing things.I read a lot about this and **** forgot much of what I read but the truth about ATF these days is it dosen't clean and lube things near as well as stuff thats designed to do just that.

 

luke please keep us posted on this.. i would never put atf in the fuel or gear oil in the tranny or blinker fluid in the piston return springs. but i am realy interested in what cummins has to say about all of this. thanks!

 

I know they are insimilar, but there is a school of thought that ATF in general is very detrimental to a diesel engine and fuel systems. This (my) personal experience disproves those theories.

I then go on to explain how I do not use ATF in our diesels, and do not recommend it when there are very good diesel specific additives out there.

I still stand by the opinion that it would do little if any harm to these fuel systems, especially when a bottle just goes into the fuel tank. The fuel filter priming is a little more dicey, but I still bet it wouldn't hurt anything. I wouldn't take the chance because there is no benefit to it, but it probably isn't anything to be spooking out about. I got a real bad tank of fuel in Nebraska one time that slimed up my filter and I had to drain the water out of the filter housing about ten times. My HPCR is still ticking, although I am sure it will die as soon as warranty is up. Stupid "technological advances."

 

I'm busted. Durn. I'd pour in just enough to keep the engine from dying and then run it up the street. Talk about a smoke trail. Did the same with Marvel Marvel Mystey Oil. Poured water down in there too. Not always warm or hot water...any old spigot water would work fine for us. Always left a nice black stain on the driveway from the exhaust pipe. Cleaned gasser engine innards like that for years. Never a problem. Wouldn't try it with todays engines though. Those intake openings or throttle body necks that lay down make it hard for the stuff to flow into the combustion chamber.