RandomHero

iTrader: (24)

well I was working on my tune and my problem just turned from bad to worse.

I got a P0757 which is a shift solenoid stuck on code and I cleared it because I had had one before and read it was just due to the higher stalling torque converter(SS3600).

So I get onto the highway normal and then do a quick WOT run and then my truck never shifts. Now I have nothing even at part throttle. I have 1 and 2 and it will go into 3 with no pressure on it, but I have no 4th and lockup.

This is sickening because I have a 7 hour drive in a week and I don't have time if it's something big.

Does anyone have anything to offer? The fluid doesn't smell burnt and I'm fixing to pull the pan to see if there is anything in it.

built408

iTrader: (10)

3-4 clutches are burnt. There is no point in pulling the pan, it's just a waste of time. The whole trans will have to come out and be rebuilt.

RandomHero

iTrader: (24)

I sure hope it isn't that. When I had the trans built the 3-4 clutch packs were replaced.

I had had a slight issue on the 2-3 shift before but never a problem with 4th gear.

Would pulling the pan show anything?

trever1t

iTrader: (14)

wow that sucks to hear Mark

chevrolet all the way

iTrader: (24)

might as well pull it out. built 408 is right. thats gonna be the problem. how many miles are on the trans?

RandomHero

iTrader: (24)

About 15k miles. I'm really at a loss on this thing. I've never had one single problem with 4th gear, and then boom. I had planned on doing a 4l80e swap, but i don't have enough time at this point. I just need a quick fix and then it's 4l80e swap time.

RandomHero

iTrader: (24)

Here's the update:

I pulled the pan and there isn't a single shaving in it. It looks great. The fluid is dark red, but not bad at all IMO. It doesn't smell burnt.

The only reason I'm thinking it's a wiring issue is because I've had solenoid codes often in the past(not just the P0757). I know that is common with higher stalling converters.

Is there any physical way to tell if there is a 3-4 clutch pack problem rather than a solenoid issue?

BlackGMC

iTrader: (31)

Can you command it to lockup or go into 4th with EFI live?

charcold-bowtie

iTrader: (10)

I know that code will through you into a third gear hold limp mode. But it doesnt sound like that.


sucks to hear.

RandomHero

iTrader: (24)

I'll have to try tomorrow, but I'm still not totally sold on the 3-4 pack being burnt up. It is definitely one of my two theories, but I'm still not ruling out the solenoids being the culprit.

Here is a list of what was installed:


sleeved input drum
new band
8 B/W high-energy clutches in 3-4 pack
beast shell w/bearing
B/W 29 element sprag
4L65 low roller clutch
Transgo HD-2 shift kit
Corvette Servo
Bushing kit
B/W clutches
Seal & gasket kit
accumulator pistons

I'm forgetting a few things, but basically those clutches have less than 20k on them and I've never had an issue with them.

The solenoids have over 120k miles which is why I'm curious as to if they went out.