My Kroil substitute (and I do have Kroil in the shop) is a 50/50 mix of atf and acetone. Acetone is available from most paint stores as well as WalMart.

I've seen a comparison test on the rust freeing properties of all the major fluids including Kroil, Rislone, MMO, WD-40, and all the rest.

The atf/acetone won. The comparison I recall used fasteners that were sprayed with a corrosive, allowed to rust tightly, then treated with the magic elixirs and loosened with a torque wrench. There was also a soak time element.


RonR


1951 3600 with Clark flatbed, T5, 4.10 rear
1970 340 Duster
1990 5.0 V8 Miata (1990 Mustang Gt Drivetrain)
1964 CJ5