One way oil
#16
Tech Rookie

which country are you from ?
#17

Another for ATF
#18

I just use plain old machine oil, 10wt specifically. I've never had a OWB in a nitro car transmission slip except if it was spun too fast and the centrifugal force caused the pinch rollers to pull away from the driveshaft, which is not the oil's fault. The pinch rollers and the driveshaft are both hardened steel, so pretty much any petroleum oil will be good enough to prevent galling.
ATF will work fine, but ATF's primary distinction is it gets sticky when squeezed into a microscopic film, and that isn't really applicable to OWBs. (ATF gets used in a lot of places where its primary distinction isn't useful, actually; it's one of those "magic" substances that some people use on everything.) Unlike the friction plates and bands in an automatic transmission, the OWB's pinch rollers have a very small contact area with the driveshaft, and the torque applied to the OWB jams the pinch rollers against the driveshaft so hard the oil film is penetrated; the OWB is held in-place by metal-on-metal contact. The oil is only needed to prevent galling when the OWB is freewheeling. You could, in fact, run the OWB dry, and in certain specific cases where I can't risk even the slightest oil contamination on nearby parts, I have done so.
ATF will work fine, but ATF's primary distinction is it gets sticky when squeezed into a microscopic film, and that isn't really applicable to OWBs. (ATF gets used in a lot of places where its primary distinction isn't useful, actually; it's one of those "magic" substances that some people use on everything.) Unlike the friction plates and bands in an automatic transmission, the OWB's pinch rollers have a very small contact area with the driveshaft, and the torque applied to the OWB jams the pinch rollers against the driveshaft so hard the oil film is penetrated; the OWB is held in-place by metal-on-metal contact. The oil is only needed to prevent galling when the OWB is freewheeling. You could, in fact, run the OWB dry, and in certain specific cases where I can't risk even the slightest oil contamination on nearby parts, I have done so.
#19

Hudy one way oil, but you need to make sure that the support bearings of the two speed are in good working order and shimmed properly...