Big smoke: is my engine sucking auto trans fluid?
 

The other day I made a 400 miles trip with my heavily loaded 3.5. I noted that when I was pressing on the gas pedal to keep my speed while driving up hill on a mountainous highway I had a big whitish smoke after a certain point. Smoke disappeared when I was easing on the gas pedal. I first thought I blew a head gasket but coolant liquid is fine as well as engine oil. Only the transmission started being noisier and it was missing between one third and half of a quart when I checked the level. Is it possible for my engine to suck auto trans fluid? If yes, is it an easy fix? How do I do that?

Thanks!

gasket leak can be small, yet whitish smoke still seen, ie water level change
inperceivable. recommend that you have a leakdown test performed.

well, being the fact that your transmission fluid, has no connection what so ever, to your engine, it's pretty impossible for your engine to be "sucking" any fluid from your trans. The transmissin cooler lines, both run from the trans, to either the internal cooler, in your radiator, or to their own seperate cooler unit.
If your car is blowing white smoke under accelleration, it sound more to me like you do in fact have some sort of a headgasket leak. Most likely, you have antifreeze, escaping directly into one or more of your combustion chambers. The result would be the white smoke, no change in oil quality, or pressure. A very slight loss in your coolant level, due to the fact that the system is pressurized, and only a few drops escape at a time, into the combustion chamber. As far as your loss in trans fluid is concerned, It seems you have some sort of leak, completely unrelated to the smoke issue. If it were as simple as trans fluid dripping onto the exhaust pipes, the smoke would be a brown or dark purple sort of color. I deal with this stuff everyday. I've seen it many times before, and made all the repairs.

Why do people hide the kind of car they have but want an answer to a question about said car?
Paul

Actually if your vacuum at the transmission fails because a membrane broke (I am guessing the modulator) you will get transmission fluid sucked in the engine. My 2 cents.

My 2 cents added to yours.

I had the same problem with a 380 engine. Mechanic nearly had the heads off before he thought of the transmission vacuum modulator valve.
Great globs of white smoke emitted from exhaust caused by transmission fluid being sucked into the manifold.

Thanks all.

pmckechnie: telling you this is a '62 220 W111 Coupe that originally came with a manual trans would certainly have added more confusion as it is now equipped with a Djet 3.5 M116 engine and a three speed auto trans that I believe was even not the type originally mated with that 3.5 engine.

a bad vacuum modulator valve was also mentioned to me on another forum. I am really not conversant with auto transmissions. Is there a way to test if this is the culprit? Is it an easy fix? Below is a picture of what I believe may be that valve as there is a pipe attached to it. I that expensive?