I WAS GOING DOWN 105, TO GET FROM CONROE TO PORTER, WHEN I CHANGED LANES TO GET NEAR AN EXIT TO GO THROUGH BACK ROADS THE TRUCK ALL OF A SUDDEN SHOT DOWN TO 42 OR 43, CAUSING SOMEONE BEHIND ME TO TRY TO AVOID HITTING ME, HE AVOIDED MOST OF THE TRUCK BUT HIT MY BUMPER ON THE RIGHT SIDE PUSHING IT INTO THE BED A LITTLE, I DIDN'T KNOW WHAT WAS GOING ON SO I SLAMMED ON THE BREAKS CAUSING THE BELTS TO TIGHTEN UP. HE GOT OUT TO HELP ME AND WE GOT MY TRUCK TOWED, HE ASSUMED IT WAS THE TRANSMISSION LOCKING UP. ONCE BACK IN HOUSTON I WAS TOLD THE TRANSMISSION WAS FINE AND IT WAS A FREAK ACCIDENT.