Trans fluid does nothing for you, besides gunk up your combustion chamber in high doses. People have stretched this myth so bad that I have heard some people say they can run their truck on straight ATF.
Yes, your truck will run on ATF. Where it stemmed from is when some guys change their fuel filters, and have no diesel to fill their filter bowl, they will use ATF instead. Running ATF as an additive does nothing for you. Yes, it does have better lubricity than diesel, especially ULSD, however it does not burn completely, leaving your combustion chamber dirty. Your better off running a diesel additive like Amsoil or Lucas or the like every oil change to help keep your fuel system clean. ULSD will not harm your fuel system. Yes it does lack sulfur, which is a main lubricating ingredient, however it is not low enough to cause any damage in any fuel system. If your fuel system failed right after you switched to ULSD, then it was on its way out anyways

 

Ultra low sulphur diesel is practically an abrassive on systems that were never designed to run on it. I know several farmers are starting to run a quart or two of new trans fluid to a tank of diesel to add some lubrication to the system. If not the injectors and pump can pretty much wear out in as little as a few years, in one case a set of injectors only lasted about 8 months and we still aren't sure how they wore out that fast.

ATF will clean an engine squeaky clean inside if you don't over do it. I ran a quart per tank for a few tanks after I got my rich condition fixed to get all the carbon cleaned out. When I swapped heads shortly there after I didn't have even a trace of carbon buildup anywhere.

 

i knew a native in saskatchewan that used to put old whiskey and moonshine in his gaspot truck....


.... two weeks later he needed another truck. I think the government bought his new used truck!!!

 

Actually, when I used to service some of the desiels when I was in college at my old shop, when changing the fuel filter we would fill it up the tranny fluid, mainly to prime it and clean it...

 

There are some truckers that will run used oil and used ATF through filters to get any contamination ( water or metal) out and mix it with full tanks of diesel... just to use it up and not just throw it away..

It doesnt hurt or help.. but its a way to dispose of used oil.
Some of these trucks are pushing a million miles and some more.. a few of them are still on the first set of injectors and pumps..

 

It can be ran, but like evrything - with moderation and it needs to be well filtered

 

you'd be suprised how many of the big truckin company's do this...U.S. Express, CRST, Werner...my buddy's used to put it in there 04 and 05 cummins as well

 

in the old diesels like the 12 valves 24 valves 7.3 and 6.9 powerstrokes and old 6.5 chcy's it is good to run a little bit of tranny fluid but not much and it doesnt make any more smoke at least none the trucks i have seen with it do

 

I would not recommend blending diesel with ATF fluid to save a few bucks. I would love to hear the discussion between a customer and service manager taking his truck to the dealer to be fixed, especially under warranty, and trying to justify why it is ok to run that type of untested/unregulated fuel.

 

As stated above if your running an older diesel engine, you are probably OK to put it in your tank. People have done it for years.

But on the newer engines like my 03 Cummins with the new age injection systems, I wouldn't. Our injectors and injection pumps have very tight tolerances and run at very high pressures. The slightest bit of contamination could plug a hole or cause binding between parts.

With today's newer tranny fluids, they have more and more friction modifiers and additives that are supposed to prevent slippage in the tranny--NOT what you want in the tight tolerances of your fuel system.

Also, you may not know exactly where the oil came from if you are running used tranny oil. Tiny pieces of metal can get through your filter and into your tank. They can also cause erosion in the fuel system with the high pressure's that it runs--could be up to 26,000 psi.

I run a pint of ashless 2 cycle oil in every tank. It should help with the loss of lubricity with the usld and is made to burn.

I would probably run it in an old beater, but not my 10K engine.

Randy