ATF & Acetone --- homemade penetrant

When concocting the homemade penetrant, does it matter what automatic transmission fluid is used? I've read that Ford transmissions can get damaged by the wrong ATF, but I don't know if the same holds true for GM cars. I'm thinking that if the GM fluid attacks the ford transmission parts, it might be more aggressive towards stuck bolts than the ford atf stuff. ???
I already have some ford fluid, but I'll get the gm if it matters. Thanks.

Any would work Marty, All tranny fluids are similar high detergent.
But I have been using Marvels Mystery Oil & Lacquer thinner for 40 years. Just another variation!
I always have had a 5 Gal. pail of wash lacquer thinner in the garage. Only draw back is if you mix a lot and it sits the lacquer thinner will evaporate out. I also use this mix when I hone cylinders.
Another old timer fix years ago was to put some lacquer thinner into your tranny if it had a seal leak. The thinner would swell the seals

Thanks. instead of making a large batch, I blended a small amount in an old Stabil container.
When doing the front forks, I use lacquer thinner as a rinse before doing the complete disassembly --- it makes the job less messy, especially if the fork oil is old old old.

Some ATF can dissolve aluminum, some can blow up transmission. I have read a story about some car, it evaporated with all passengers and tires. Nothing was left , just some dark spot on pavement. So you better read label on ATF bottle. :laugh:

I've thought about doing this what do you mix it at 50/50 ?

yes 50/50 mix. I swear by the stuff now