had same problem with my 75 Laguna when i bought it an trailored it home from N.Y. , anything over 45mph and the trailor would start fishtailing severely ....after abought 50 miles of that nonsence i got to a place to refuel the truck and unbuckled the Laguna an brought it as far forward on the trailor as i could and was smooth sailin the rest of the 200 miles home .
