I know, I know, low post count Newb in desperate need of an already covered topic. Well here's my novel, thnx in advance for your patience.
Ok. 2002 LB7 5-speed Allison 1000. Banks 6-gun, full exh, and K+N... So no REAL upgrades. 150k,no load, and I drive like a grandma.
On the hiway yesterday getting up to speed, and tranny dropped out of gear and RPMs reved up. Pulled over and found nothing wrong. Another 20 mi, and once again out of gear, engine revs. This time I get a SES light. Tranny seems to degrade slowly. Little power to the wheels, no reverse, you know, limp mode.
Got home, truck off, cleared codes which were:
P0735 (gear 5 ratio incorrect)
P0840 (transmission fluid pressure sensor/switch A circuit malfunction)
P0700 (transmission control system malfunction)
And all back as if nothing happened.
In paranoia, I drained the pan straining the fluid, pulled the spin-on filter cut it in half, and dropped the pan. No clutch shavings, metal chunks, or signs of catastrophe; also fluid was deep red, and not burnt.
Normal silt on magnet:
I re-serviced with Valvoline full Synth Dextron lll, new filter, and assembled.
Drove to work today, slipped out on the way there, and once on the way back. I put it in tow/haul, and it didn't slip again.
I've searched this and other forums but am unable to find someone with this particular code combo. I need to tow my rock crawler 2hrs each way this weekend, so I need a direction to go in.
Leaning on it being an electrical issue rather than mechanical judging by what I'm seeing.
Any advise is muchly appreciated.
Ok. 2002 LB7 5-speed Allison 1000. Banks 6-gun, full exh, and K+N... So no REAL upgrades. 150k,no load, and I drive like a grandma.
On the hiway yesterday getting up to speed, and tranny dropped out of gear and RPMs reved up. Pulled over and found nothing wrong. Another 20 mi, and once again out of gear, engine revs. This time I get a SES light. Tranny seems to degrade slowly. Little power to the wheels, no reverse, you know, limp mode.
Got home, truck off, cleared codes which were:
P0735 (gear 5 ratio incorrect)
P0840 (transmission fluid pressure sensor/switch A circuit malfunction)
P0700 (transmission control system malfunction)
And all back as if nothing happened.
In paranoia, I drained the pan straining the fluid, pulled the spin-on filter cut it in half, and dropped the pan. No clutch shavings, metal chunks, or signs of catastrophe; also fluid was deep red, and not burnt.
Normal silt on magnet:
I re-serviced with Valvoline full Synth Dextron lll, new filter, and assembled.
Drove to work today, slipped out on the way there, and once on the way back. I put it in tow/haul, and it didn't slip again.
I've searched this and other forums but am unable to find someone with this particular code combo. I need to tow my rock crawler 2hrs each way this weekend, so I need a direction to go in.
Leaning on it being an electrical issue rather than mechanical judging by what I'm seeing.
Any advise is muchly appreciated.