I just picked up a '73 f250 390/at.

I noticed a giant white smoke cloud coming from it when I came to a stop. Take off and its fine, sitting also. I came down a hill and when I hit the brakes at the bottom it billowed smoke again. And not just a little smoke. Like James Bond smoke screen! I can't see cars through that smoke.

Any ideas what might do that? Seems to be when I brake hard or come to a stop at the bottom of a hill or something.

 

over filled with oil, oil galley holes clogged in the heads and the PCV sucking oil?


These are things I've seen happen.

 

Its on the high end of full for the oil. But wouldn't that blow out a blume of blue smoke if it was oil?

 

Double check your trans modulator isnt ruptured and sucking ATF through the vacuum line. Not sure if brake fluid would cause that much smoke, but since you said its when you brake hard- pop the top off the master cylinder and check the level. Pull the vac hose off the brake booster and inspect for fluid. You could have a master cylinder leaking at the back, and its sucking the brake fluid through the booster.

 

It seems to like to do it when its pointing down a hill. I came to a stop on a hill just a bit ago and after about a minute it started blowing smoke from out the bottom. I'm not sure where its even coming from, I don't think its from the exhaust even.
Sure is a ton of smoke though!