Ok I am working on a truck that my buddy used to own. It has a stg 4 suncoast old kit and my old 1057 in it. Here's where I'm at. The truck will go into reverse fine, but when engaged into forward gears the tranny locks up like its stuck in 2 gears. It has no codes set currently, only abs light is on. Before the truck was brought to me the owner pulled codes with a little handheld hobby from harbor freight and he was able to get a p0751, p0756, c342d, c3064, c2174, and p0843. With efi live scan tool I can activate 1st gear and the wheels will take off spinning. DIC is flashing shift range inhibited. I can activate all gears and TCC with efi live but as soon as I deactivate it it locks back up. I'm pulling pan as we speak to ohm solenoids and was going to pull valve body and check trim valves to see if they are stuck and clean thoroughly. Anyone else have any ideas? I'm stumped by the abs light with no code.
Allison 6sp: Reverse good, no forward gears, no codes!
- Thread starter BigDMax05
- Start date
Has anyone ever had a clutch pack stick engaged? The story I just got from this guy is he was leaving a gas through an intersection, light went yellow he floored the go pedal, spun tires, drove about another 6 blocks and said the truck felt like it was bogged down. Went home parked it for lunch and went to get back in it and it wouldn't go. I have disassembled the vb and its straight nasty inside. The mesh screens over the sol's A + B were both caked with what looks like clutch material. Inside the vb there are gunky deposits in the corners and transitions. Dirtiest one I've taken apart. The fluid I drained is burnt bad and pretty hazy. I'm thinking that a clutch pack is stuck engaged cause like I said up top it will go backwards but in forward gears it acts like 2 opposing clutches are engaged.
C3 would have to be stuck for reverse to work and no others. BUT you said it will move when commanded with EFI, so it might be ok....? Either way, sounds like the vb needs a little TLC.
well I cleaned the vb and reassembled. no stuck trim valves and all solenoids ohm'd out good. changed little cone filter (old one was full of clutch material). Gonna go ahead and pull tranny this week and see whats going on. ill post up my findings later on.
Yes I know, but it brings to question why the wheels spin when commanded by EFI DVT controls.
I assume your commanding 1st gear but is it really first gear or is it in limp mode and just rolling ? I have had this happen to me before where the clutches or steels warped ,lost all clearance could not release so they were tied up (stuck engaged).
Bad enough that trying to go from forward and reverse with mild go peddle pressure the rear tires would chirp!
Your transmission and torque convertor and cooler and valvebody is going to need a heavy flushing out of debris! Anything left behind can muck up the valvebody giving you fits.
Bad enough that trying to go from forward and reverse with mild go peddle pressure the rear tires would chirp!
Your transmission and torque convertor and cooler and valvebody is going to need a heavy flushing out of debris! Anything left behind can muck up the valvebody giving you fits.
I had c1 welded together. Would go forward in drive and reverse(obviously hard to do so) and would try and drive threw the park pin. Valvebody was a mess, but in hopes I cleaned it and replaced all solinoids, same thing. Finally dropped tranny and wasn't much left haha. Stock clutches doing a brakestand with a dually. Last brakestand I have done with an Allison I think haha.
Edit: only nice thing about the whole pack stuck together it was surprisingly easy to remove from splines. Nothing like warped packs atleast.
Edit: only nice thing about the whole pack stuck together it was surprisingly easy to remove from splines. Nothing like warped packs atleast.
I believe it was rolling limp mode like you suggest. Shift range inhibit on the DIC! The converter is getting sent back and rebuilt. I am going to sell him a 1056 and my suncoast out of my dually for times sake. He has been w/o truck for a couple of months.