check your motor mounts

[beardeddummy]

I had a motor mount give up the battle and it busted my transmission case. so a 35 dollar part can save you a transmission rebuild

 

[BerHntr]

I guess I've gotten lucky, the passenger side mount in mine has been broken for a while now. Motor kind of tilts under load only in reverse. I had a Mazda b2300 for my first truck and when I got it both mounts were broken, the shifter would slap the passengers knee if I took off to fast