Hope you don't mind, but I think you might be one of the few people that can answer this since you build our trannys for a living.

My gut tells me my tranny is just fine, but it's doing something that has me a bit puzzled. Brand new, I did a few burnouts in a row and the 1-2 shift went mushy from 1k miles to about 12k miles. Chip or no chip. All other gears were fine. Then it cleared up for no apparent reason and is hitting hard again and has for the last 2k miles.

For the last 1k miles, my 2-3 shift has gone soft (like stock) for no apparent reason, but only at part throttle. If I give the truck 1/2" of pedal and hold it there from a light, 1-2 with the help of the line valve and chip is smacking hard, 2-3 feels stock and the 3-4 hits hard. Full throttle they all hit so hard it squalls the tires rather than chirping, so I don't think it's slipping and there's no unusual noises.

I'm baffled. Any ideas? It's almost like a piece of junk is floating around in the passages and plugging something intermittently. The 1-2 shift finally cleared it's throat after 11k miles and now 2-3 has it but not as badly because at least it chirps at full throttle. It really seems to work exceptionally well except for the one soft shift.

Thanks.

 

Could be a sticky "310" valve in the accumulator, the line mod boost valve you installed could be sticky or you may have glazed the clutches. It's real hard to diagnose without at least driving the truck ( and actually, I'm not real good without a test stand, occupational hazard). I'd keep track of what it does and when, and keep bugging the dealer if you think it's got a problem. I'd not mention the line mod valve, because if it's the problem they won't cover it under warranty. What kind of kit are you using? Did you just do the boost valve or did you tune the induvidual shift bores? I wouldn't be surprised if a line valve without doing the shift bores could make it a little squirrelly, the computer is figuring out how to shift it and the boost valve is tweaking line pressure without some compensation in the other bores, this may be confusing it. I've found that if you change the boost valve, you really have better results if you tune the bores with eihter shims or springs. ( my shift kit uses heavier springs).

E-mail me, we can get into more detail.

Hope it helps,

G
GBEvans@peoplepc.com