PDA

View Full Version : Automatic Transmission Fluid



PeterAC
23rd June 2009, 04:21 PM
I have now heard of two uses for ATF. One was for an injection/ valve clean by adding to the startup fuel and the other is to use as an engine crankcase cleaner by topping up engine oil just prior to changing the engine oil. It gives a more thoroughclean out of engine? Are there other uses, do they work, and what is it about ATF that allows it to do these jobs?

Peter<><

PeterAC
23rd June 2009, 07:36 PM
Oh yeah, make that three uses, I happen to have it in my gearbox too:)

Peter<><

yorta2
23rd June 2009, 10:23 PM
Dave I can't agree with you on leaving sludge build-up in engines, particularly for older diesels and those (such as older Toyota Surfs) that produce large amounts of ash. Try using a flushing agent (like CEM's product or even Nulon) and see just how much extra oil you get from your first oil drain - quite a lot more than normal, even taking into account the additional fluid that you added as a flush. And it will be much dirtier too. Long term buildup of sludge will cause diesel engines to 'expire' much earlier than a clean engine. Also, the buildup under piston skirts (stained dark brown) provides an 'insulating layer' that reduces the cooling effect of oil as it is sprayed under the pistons, thus making the engine run just that bit warmer - not always a good thing.

ATF might assist in such flushing, but I wouldn't guarantee its effectiveness as a lubricant in a diesel engine. CEM is about the best you can get. Have a read of this:
Cost Effective Maintenance - Home (http://www.costeffective.com.au/) and click on the 1992 Landcruiser story, for a good idea of what I am talking about. However, whichever commercial flushing agent you choose, follow their instructions closely. My engine runs better and cooler since flushing it, and I did it on a couple of drains - e.g., flush/drain, then 5000km later, just drain, then next 5000km, flush/drain - it did wonders. Oh, and the oil stays browner for longer after a flush too.

Alga
24th June 2009, 09:38 AM
ATF has a multitude of purposes, it's designed to clean, cool, lubricate, transmits force and pressure, inhibit varnish build-up and protect the transmission. Most contain combinations of rust preventatives, anti-foam additives, detergents, dispersant's, anti-wear additives, anti-oxidation compounds, surfactants, cold-flow improver's, high-temperature thickeners, gasket conditioners, and petroleum dye. ATF and hydraulic oil, a close relative of ATF undergo the same high heats and pressures.

Sludge build up occurs in very combustion engine, they rely upon the production of carbon and other toxic gases to operate, so must by pure physics create residue build up under the pressure and explosives forces they operate under. Racing car engines are always pulled down cleaned and rebuilt after racing and if you believe the ad's on their cars, they use many additives and cleansers for their engines.

I've used straight ATF in the fuel system in the same way you use nulon or liquid moly, by introducing it straight into the fuel system. We used it on a Datsun 720 which had never had a thing done to it in over 253000 klms spent on a farm, had the oil changed about twice and was running terribly that we bought cheap at an auction. We put a litre of ATF through the system and flushed the engine with it as well, at the time we had no access to degreasers or flushes, but plenty of ATF and hydraulic fluid on the property. I sold that a few years ago locally and it is still running round the country side.

As Yorta2 says, flushing your engine keeps the oil cleaner for longer and after 500000 klms my engine runs well, but a bit gutless and has been flushed regularly, so it seems to work for me and others who operate this way. I'll be interested in what the engine looks like when we pull it down early next year, may even take some photo's an post them as te results of 250000+ on WVO and 250000 on dino.

yorta2
24th June 2009, 07:46 PM
Thanks Alga. I have also used ATF after a fuel filter change. I fill the filter housing with ATF (not necessarily new stuff), drive the car for a few kms like I stole it then, by that time, I feel the injectors have been cleaned enough to get me through until the next filter change. On the other hand, I have found that using B100 has kept my injectors clean anyway, but I wonder if the ATF is assisting, and so won't change my habit.

PeterAC
14th July 2009, 03:13 PM
Alga and yorta2 I believe that more is not always better, therefore, is there any reason from your experience a benefit in using ATF as in a blend to act as a cleaner or as a stand alone fuel (such as waste motor oil). I am curious if there are benefits. If so I'll try to track down waste ATF filter it and use and see what happens. At worst I'll track the waste ATF to use as the system cleaner every 5000kms. As a system cleaner would waste ATF be sufficient or best to use new ATF. What are others experience.

Peter<><

Alga
15th July 2009, 12:37 AM
Peter, used ATF like other used oils, normally have lost their additives and replaced them with contaminants. Filtering will remove the contaminants, but not replace the required additives. I see no reason why you can't burn used ATF and other oils in the engine after filtering, that doesn't require additives to do the job but to clean the fuel system and particularly the injectors, you require additives designed to do that. ATF has them all and at much cheaper prices than commercial cleaners.

As to the benefits, my hj60 has done over 250k on veg and over 500k over all. It's never had the injectors or pump touched and there's a noticeable difference after I put a litre through it, either straight or blended in the starter tank. Straight works best.

PeterAC
15th July 2009, 09:51 AM
Thanks Alga

Peter<><