ATF in Oil

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Personally iv never done it. And I wouldn't suggest it either. Back in the day when motor oils where non detergent ATF had high levels of detergent and it was used to help clean engines. Was it the best option then? Not really Best option now? No chance There are many good cleaners out there that cost just as much as ATF why not try those?
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Its not a good idea . Modern atf only contains about 10% of the detergent potency of modern api sn motor oils. The atf would actually dilute new oil. If we are talking about adding it to an oil burner that was low on oil, then why not it would refresh the additive package but could change the viscosity sincere most atfs are pretty low on that range. That being said topping off with the correct oil is the better choice.
Don't believe everything you see on TV.Just because somebody says something (like disconnecting the alternator while its running) doesn't mean its true or correct.Means they are incorrect.
Like most urban legends, this one might have some basis in fact. Way back in the day, some ATF formualtions contained whale oil, an ester. Since esters are highly polar and the motor oils of the day had little detergency, these ATFs might have had a cleaning effect. I wouldn't use ATF with any modern oil and anticipate that it'll do anything positive. Having said that, you can find a few posts on the site in which members swear that they've used ATF as a cleaner with good results.
This probably had its place back in the days of low detergent oils, but todays oils dont have that problem. No need for ATF in motor oil. Use Pennzoil if something needs to be cleaned up.
I have heard of this aswell, but like said above there are allot more detergents in modern oils so it does not seam to necessary. I used to hear "old school" mechanics talk about this. It seams to me kerosene would work better (if you must !), I used to hear about this allot also. I have seen it done and it was scary the amount of [censored] that came out of early 70's 440 RV motor !
Originally Posted By: bobbob
On an episode of Car Chasers they put some ATF in with the oil claiming it will reduce sludge. Has anyone heard of it and have you tried it? Thanks
I've used ATF in the oil before. It didn't reduce the amount of sludge. It just reduced the amount of ATF I had in my stash. You can try it if you're dying to find out the truth, but as everyone else has mentioned, don't bother. Regards, JC.
Lubrizol is one of the major manufacturers of additives to lubricant blenders (along with Chevron Oronite, Infineum (ExxonMobil & Royal Dutch Shell), Afton, few others). Here is the list of ingredients in the additive package they sell to ATF makers: Dispersants... Sludge & varnish control Antioxidants... Prohibit oxidation Antiwear... Planetary gear, bushing, thrust washer protection Friction modifier... Modify clutch plate and band friction Corrosion inhibitor... Prevent corrosion and rust Seal swell agent... Prevent loss of fluid via seals Viscosity Improver... Reduce rate of change of viscosity Pour Point Depressant... Improve low temperature fluidity Foam inhibitor... Foam control Red dye... Identification Note--NO detergents.
Yes, in my opinion it will clean up an engine. I had a ford with inline 6 cyl that had a couple of hyd lifters that were sticking and hammering away. Had a friend and also a mechanic tell me to add some atf to the oil, so I did and those lifters got quiet and worked fine for about a year. Eventually they started getting sticky again so I pulled the cyl head and replaced them.
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