Hello. Been doing some reading here and learned a lot, but would like to narrow this down. I found and printed moosehunt's thread to pore over.
My truck is a 12/92 Chev 2500 4wd 6.5 Turbo with Banks kit, 190K miles, owned 12 yrs, and have serviced it regularly.
Only repairs to date have been injector pump w/fsb new hydraulic head, injectors rebuilt, timing kit and water pump at 162k,
other than brakes, shocks, radiator, and a Pitman arm. I do need to pull the steering wheel and replace a bad wiper switch lead,
apparently. I’ve never had an auto tranny apart. Please excuse the detailed long post, as an attempt to give you enough info to
help.
First occurrence other than the idiot light flashing a very few times so fast I couldn’t tell which one on the highway was loss
of 3&4 when slowing to exit the freeway with a trailer on. After stopping to check, I continued to the job site. Borrowed a
Riley’s reader that day and got “vehicle not responding”. Put Sea Foam in, drove it around. Went to a tranny shop where I know
them to get it read but the light went out and it worked perfectly, including highway test, and no error codes would read.
Thought maybe I had cleaned a stuck valve or solenoid and drove it. Light came back on the next day and I only had 1 & 2. Ran
it back to the shop, the light went out, and it wouldn’t respond at first to the reader, then connected and no error codes, then
worked perfect on a freeway test run with the reader connected and trailer on. Dropped the pan, inspected for loose connections,
serviced. Absolutely clean and no metal. Some rear seal seepage showing but fluid not low at any time.
Went to the job site to load up to go 350 miles home over mountains. When I left the next day, the service light was on and I
only had 1&2 again. Prayed. 1 mile later it kicked in, and I made it home with only two brief flashes of the light and no
problems, with at least a ton of payload over mountain passes.
Pulled pass-through plug off case, found a little fluid, so cleaned pins w/ brass brush, coated with dielectric, then made
perfect 10-mile test run. Made it home from next job a week later last 20 miles in second gear, pulled plug again, cleaned, no
dielectric grease, problem remained intermittent, sometimes changing with engine off-time, even cycling the ignition, but no
constants. Got nearest dealer on phone. They want $390 I don’t have for an FSB retro-updated plug/ harness kit out of Memphis,
[24200161], claim they can no longer access the old factory service bulletin to see if the plug can cause this problem. Pulled,
inspected, cleaned remaining trans & transfer case plugs, still intermittent. Hauled necessary hay trailer and grain in 1&2 with
no problems, still intermittent 3&4, but less often when hot.
Found a local guy with a reader, got there with light on after several tries, (seems more likely after considerable
driving), “vehicle not responding”, no stored codes. He tried jumping the right pins for flash codes from his book and nothing.
He says it has to be electrical problems.
Had to haul trailer local again, so pulled the trans fuse on a downhill to see what gives. Light went out, defaulted to 2nd
second only. I thought it was supposed to “limp” in 3rd?
Shut off truck, plugged fuse back in, light went out, hauled trailer over 5 miles at 55 in fourth before it went “neutral” and
light came back on. Hauled hay home in 1&2. Nearest shop claims they can read it even if it won’t talk for $50 with their new
$2500 computer reader, charged me $20 to print some nearly illegible wiring diagrams off their computer service. I will cough it
up so long as they will agree not to charge me if they can’t read it, but need to see any error codes, and need more research
first, since apparently these can false solenoid codes from a bad ignition switch or PCM/ECM, and don’t want to be at their
mercy. I would also want them to read the thing on the road in 2-3 shift if possible. The first thing they said was “bad
intermediate seals” (rebuild), which may reference 2-4 servo assembly piston seals bad. Would that be intermittent? I have
since printed decent internal and external wiring diagrams from msgpio.com at a library, (don’t have internet), together with a
range reference chart for the solenoids, but lack a physical location diagram or photo for the solenoids to ID which is which, so
will keep looking. Suggestions?
My next step as soon as I can do without this thing for a couple of days is to drop the pan again, start checking resistance on
the plug and solenoid circuits, hopefully find a way (air?) to make sure they are good. Are these hard wired and if so what sort
of splices should I use? Can I jerk them, unplug the trans, and apply voltage to check operation individually without cutting
them loose? Is there a simple check to verify the pressure switch manifold circuits are good?
Can the 3rd accumulator ball and retainer assembly (check ball #7), stick intermittently, and would it get worse when hot? I’m
leaning toward electrical circuit problems or solenoids misfiring, but don’t want to take the wrong track through ignorance.
Advice, comments, questions welcome. We are in fly-over country, the nearest library is only open twice a week for half a day,
and no, the money isn’t even there for a rebuild, so please be patient. I was an ET and electrician when Moses was a baby, am a
decent troubleshooter by sectionalizing, but this control system is a maze without perfect maps and known physical locations of
components. Thanks kindly.
My truck is a 12/92 Chev 2500 4wd 6.5 Turbo with Banks kit, 190K miles, owned 12 yrs, and have serviced it regularly.
Only repairs to date have been injector pump w/fsb new hydraulic head, injectors rebuilt, timing kit and water pump at 162k,
other than brakes, shocks, radiator, and a Pitman arm. I do need to pull the steering wheel and replace a bad wiper switch lead,
apparently. I’ve never had an auto tranny apart. Please excuse the detailed long post, as an attempt to give you enough info to
help.
First occurrence other than the idiot light flashing a very few times so fast I couldn’t tell which one on the highway was loss
of 3&4 when slowing to exit the freeway with a trailer on. After stopping to check, I continued to the job site. Borrowed a
Riley’s reader that day and got “vehicle not responding”. Put Sea Foam in, drove it around. Went to a tranny shop where I know
them to get it read but the light went out and it worked perfectly, including highway test, and no error codes would read.
Thought maybe I had cleaned a stuck valve or solenoid and drove it. Light came back on the next day and I only had 1 & 2. Ran
it back to the shop, the light went out, and it wouldn’t respond at first to the reader, then connected and no error codes, then
worked perfect on a freeway test run with the reader connected and trailer on. Dropped the pan, inspected for loose connections,
serviced. Absolutely clean and no metal. Some rear seal seepage showing but fluid not low at any time.
Went to the job site to load up to go 350 miles home over mountains. When I left the next day, the service light was on and I
only had 1&2 again. Prayed. 1 mile later it kicked in, and I made it home with only two brief flashes of the light and no
problems, with at least a ton of payload over mountain passes.
Pulled pass-through plug off case, found a little fluid, so cleaned pins w/ brass brush, coated with dielectric, then made
perfect 10-mile test run. Made it home from next job a week later last 20 miles in second gear, pulled plug again, cleaned, no
dielectric grease, problem remained intermittent, sometimes changing with engine off-time, even cycling the ignition, but no
constants. Got nearest dealer on phone. They want $390 I don’t have for an FSB retro-updated plug/ harness kit out of Memphis,
[24200161], claim they can no longer access the old factory service bulletin to see if the plug can cause this problem. Pulled,
inspected, cleaned remaining trans & transfer case plugs, still intermittent. Hauled necessary hay trailer and grain in 1&2 with
no problems, still intermittent 3&4, but less often when hot.
Found a local guy with a reader, got there with light on after several tries, (seems more likely after considerable
driving), “vehicle not responding”, no stored codes. He tried jumping the right pins for flash codes from his book and nothing.
He says it has to be electrical problems.
Had to haul trailer local again, so pulled the trans fuse on a downhill to see what gives. Light went out, defaulted to 2nd
second only. I thought it was supposed to “limp” in 3rd?
Shut off truck, plugged fuse back in, light went out, hauled trailer over 5 miles at 55 in fourth before it went “neutral” and
light came back on. Hauled hay home in 1&2. Nearest shop claims they can read it even if it won’t talk for $50 with their new
$2500 computer reader, charged me $20 to print some nearly illegible wiring diagrams off their computer service. I will cough it
up so long as they will agree not to charge me if they can’t read it, but need to see any error codes, and need more research
first, since apparently these can false solenoid codes from a bad ignition switch or PCM/ECM, and don’t want to be at their
mercy. I would also want them to read the thing on the road in 2-3 shift if possible. The first thing they said was “bad
intermediate seals” (rebuild), which may reference 2-4 servo assembly piston seals bad. Would that be intermittent? I have
since printed decent internal and external wiring diagrams from msgpio.com at a library, (don’t have internet), together with a
range reference chart for the solenoids, but lack a physical location diagram or photo for the solenoids to ID which is which, so
will keep looking. Suggestions?
My next step as soon as I can do without this thing for a couple of days is to drop the pan again, start checking resistance on
the plug and solenoid circuits, hopefully find a way (air?) to make sure they are good. Are these hard wired and if so what sort
of splices should I use? Can I jerk them, unplug the trans, and apply voltage to check operation individually without cutting
them loose? Is there a simple check to verify the pressure switch manifold circuits are good?
Can the 3rd accumulator ball and retainer assembly (check ball #7), stick intermittently, and would it get worse when hot? I’m
leaning toward electrical circuit problems or solenoids misfiring, but don’t want to take the wrong track through ignorance.
Advice, comments, questions welcome. We are in fly-over country, the nearest library is only open twice a week for half a day,
and no, the money isn’t even there for a rebuild, so please be patient. I was an ET and electrician when Moses was a baby, am a
decent troubleshooter by sectionalizing, but this control system is a maze without perfect maps and known physical locations of
components. Thanks kindly.
