My 89 Sub pulls hard to the left when hard braking when I am towing and it does not seem to matter the size or weight of what I am towing. It did it the first time when I was towing 55Willys Jeep back from Mary's peak. The trailer was really heavy and I had a lot of tongue weight. But we both about crapped ourselves when I had to brake hard and we did an automatic lane change in the process. Then today I am towing a Honda Foreman Quad on my lightweight ATV trailer and out of the mountains it starts pulling hard left everytime I touch the brakes. WTF is going on? I have done emergency braking proceedures while not towing to test the brakes and it stops straight as an arrow.