With a performance rebuild how much power can the 4 speed auto in our trucks hold? What would have to be done to make it live behind a motor putting out 800-900 crank horsepower? Is this even an option for this transmission or would a C6 and a gear vendors splitter unit be better? Sorry have alot of questions about this trans. Thanks for any input.

John..
2000 Silver Lightning

 

They can handle a lot, but 800-900 crank HP is more than I would try without SERIOUS modifications, way beyond what a do it yourselfer should try.

G

 

Papabear,

It is strong enough to take over 550HP on the ground and nearly 700Lbs of TQ on the ground for the life of the truck up to a month ago when the 1-2 clutch pack went out. In that time it has taken several 1.7x 60's. But when you pound something that hard, for that long, something is going to break. One thing we did do was put a deep 4x4 pan on it and a 2800 GBW tranny cooler on it. Keeping these things cool will help the life of em.

 

So Factory_Tech, all I have to do is change the front clutch pack and a line mod valve to ensure my trans will live happy behind a chipped/filter/pulley blower motor? Your opinon is greatly appreciated.

 

Factory_Tech,

I do not have a problem having serious modifications done to the transmission. I just need a company or to know what parts will make this transmission last behind that type of power. I have checked some transmission places like level 10 and only see rebuild packages but before I start calling I would like to know more about what it is going to take.

Lightning Boy,

What kind of mods do you have to put 550hp and 700ft-lbs to the ground? And at this power level have you had any problems with the rear end? Thanks for any information you can provide.

Thanks,
John..
2000 Silver Lightning

 

Papabear,
I do build some modded transmissions, but I'd pass on doing this one not because it cn't be done, it can (try Level 10, or Jet) but just because if I built anything for that kind of power I would have to do it on an "as is" basis and I don't want the resposibility to tell you the truth. It's just more than I ussually do and I have no way of testing things which I think would make it way to experimental for me to feel comfortable charging someone something to the tune of $3,000-4,000 dollars for. I hope you find someone, try the ones I mentioned above, they just have a lot more resources to test (and warrent) a box of that level.

Good luck,

G

Gator,
it's not exactly that simple, but doing a box for a chip, filter and pulley is a much more straightforward application, and I do build things that will handle that. You can start for under $500 and do a complete box for about $2,000 plus shipping. I'm not promoting my own work here, several people and places can do this and I encourage you to look around, but if you want one, contact Sal and I'm sure we can work something out.

 

I'm pushing right at 400 RWHP and have tore my transmission out thrise. The sad part is that it's not like a light switch, it just doesn't happen at any given point.... like clock work. But it builds up to the point where you just sit there smelling something going wrong or you'll hear and feel it.

Either way, now I have an extra 4 quart transmission oil pan, 30,000 GTW transmision cooler, and a $600 level 10 extra plate rebuild kit.

So far so good. So to answer your question after trashing 3 stock transmissions as well as talking to un-modded owners, the stock transmission can handle about ~ 330 RWHP without trouble. This assumption isn't taking into consideration that the chippers are upping the transmission line pressure, so this could be the limmiting factor why some are having problems, but that's only a guess on my part and not a fact.