i was on the way home tonight in my 96 k1500 company truck it has a 4l60e which i really like its never given me no trouble and it has over 280k on the truck. it had a little over 200 when i got it. and the transmission was rebuilt at 170k but it went out with no warning tonight i was comeing up a hill and heard something break. it would slip really bad but then it would catch and go on but it got me home . well anyways what i am thinking about now is.. i have just bought a 205 and a 700r4 and a adapter that goes in the 700r4 .to put in my 79 k20 with 4;56 gears .it has the turbo 400 in it now but it really whines out with 35s so thats why i bought all this to make it drive better. but now i wonder if i should try going to a bigger lift and bigger tires to see if it will do better than swapping to an overdrive i have never had any trouble with the 400 so what do you guys think i should do? go with the od or try bigger tires?