'90 Suburban. 350/th400/241. Driving down the interstate with a heavy trailer. Smoke comes pouring out from underneath. Looks like a fluid leak. starts from just at the back of the engine. Looks to be coming from the drivers side only. Reddish in color (Trans Fluid?). Does not appear to be coming from the bottom of the trans, looks like its higher up. Hit the Y-pipe which caused the smoke.