i will give a little background. my name is jonathan and i am new to this forum. i am currently in iraq but will be home in a month. i have set myself up a little project but ran into quite a snag. alright i have a 1965 Chevrolet K20 3/4 ton 4x4. i am going to swap the entire drivetrain. i am installing a 6.6L duramax turbodiesel, new transfer case, two new axles ( probably dana 60 front and dana 80 rear with 3.54 or 3.73 gearing) and new transmission.
i have run into a tranny issue and need some help from people who know. my LB7 will put out 520 ft lbs without modification. it has a turbo so i am sure it is doing more than that already. the ZF S6-650 transmission that i originally wanted for this truck can only handle 520 ft lbs. so i need a later model zf that can handle this or a similar 6 speed that can cover up to 750 torque that i will probably be putting out someday in the near future after this build. i am also trying to figure out if i can floor mount controls for an allison. it needs to be floor mount. not sure which way to go with this. dont know alot about trannies used for high torque motors. if anyone could help i would appreciate it very much. thanks
Jonathan

I am one of the few that has manged to over power a ZF6. Trust me they will handle far more than 520ftlbs. ;) My puller uses the stock ZF6 that came with it. I did manage to break it try to sled pull in high range. But this is not common. To make the kind of power needed to out right break one you will need a built motor. So if you plan on running a tuned stock engine all you will need is a upgraded clutch and you should be fine.:cool:

PS Thank You for your service to our country!

JOHNBOY is correct. They can handle alot of abuse and alot of added power. All you need is a very good clutch to hold the power.
I want to say thanks second for your service to our country!!

Dan

Glad to see ya made it over Jonathan. These guys will reinforce what we have already talked about. SoGrand is the guy you need to PM about ZF6's and parts.

WOW thanks for the info now i dont have to change my plans. that is a wonderful weight off my back. i want to thank all of you on behalf of every soldier marine sailor and airmen here in iraq for all your support and for giving us a true reason to fight the battles we fight. the only other thing i need to know about the tranny is where to get a refurbished ZF S6-650 and a manual transfer case for it. but preferrably without core charge as i dont have a zf to give them in return. just an old 4speed granny low out of the K20.
also the max torque i will mod this motor to anywhere in the next five to ten years will be 750 ft lbs. so what is a good clutch/torque converter to get for that? that isnt super expensive. thanks again guys
Jonathan

Southbend clutch all the way!

ok thanks i will check it out. how am i gonna choose what clutch i need for it? i wont be pushing more then 750 ft lbs for a long time. and i wont be doing that til after this build when i can afford a programmer so it will be a couple years. i am just not sure what stall speed and all that stuff that i am gonna need for this motor and tranny. thanks
Jonathan

no stall to worry about on a standard. Getting a clutch should be pretty straight forward

alright thanks alot. i am looking into them now. thanks
Jonathan