I've been having trouble out of my "bullet proof" transmission for awhile now. It has a suncoast billett triple disc convertor, suncoast valve body, extreme duty clutches, a billett flex plate, and a deep pan.

since day 1 of the rebuild it has had the following problems:
seems to jump between 1st and 2nd gear at about 15mph.
slips in 3rd gear during light throttle
shifts through all gears fine during wot, but seems to slip under light throttle

I have been back to the shop that built it 5 times since it was built 4 months ago, complaining about these things each time. Every time I was there the guy kept telling me something was wrong in the valve body and he kept playing with different springs.

I called him monday the 8th about bringing it back in, and once again he thought it was the valve body and told me to wait until thursday for him to get the parts in. well I was driving down the road wednesday with my bd set on stock trying to baby it until I could get it in the shop, and it went crazy in 3rd gear. It would shift 1-2nd fine then once it hit 3rd it would just slip, when I could get it through 3rd it was fine in 4th. So I called and the owner of the shop said he was going out of town and I wouldnt be able to bring it in until monday. So I kept being easy on it, and it seemed alot better, it still had the original problems, but 3rd gear was nothing like it did wednesday.

I dropped the truck off sunday night at the trans. shop and the owner called me monday saying that it was burnt up again.

is there any common problem that would cause these issues, or do you all think there may be something he is messing up on? or possibly a crack in the case?

I want to help him come up with ideas, because when I get it back I'd like for it to be right this time

 

Sounds like the VB to me. I had kinda the same problem with my Allison after I had it built. I had a new VB from suncoast installed and the trans worked perfect.

 

I just noticed that you have the suncoast VB. Have you called suncoast and talked to them about it. When I was having problems I gave them a call and we got it figured out. Good luck

 

let us know what you find out.

 

The trans giy called me today and siad that there were some problems with the valve body, so suncoast is sending a new valve body that is supposed to be set up to help with the 121212 shift and apply more pressure

 

I hope that fixes your problems nothing sucks more than a tranny that doesnt work right.