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DTC 68 - Transmission Component Slipping

Good evening. Quick update: I've tried to clear codes via the brake pedal/ gas pedal method and the pull the fuse(s) for 10+ seconds to no avail. Still shows code 68 without even starting the truck.Frustrating here....Mark
 
I was just thinking about you.

Pretty sure the brake pedal trick wont work on our trucks.




Edit, just looked at my wiring diagram. Constant 12v comes in on "A12" @ the TCM, it looks like it has a fusible link tied to the power distribution block.

You could unhook it @ the P-block or unhook the batts(pain in the Arse). You could also put a toggle switch on that "A12" wire if you didn't mind splicing one in, that would cut down on parasitic loss while the truck was parked for long periods also.
 
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midniteplowboyy said:
I was just thinking about you.

Pretty sure the brake pedal trick wont work on our trucks, try pulling fuses, ECM, TCM or anything else you can think of that might feed power to it. It will be a fuse thats hot with the key off. The only fuse in the engine compartment at the power distribution block is for the fuel pump correct, I cant remember.

I think if you pull the right fuse it will kill the check engine light, key on engine off.
Click to expand...

Agreed, I was told after the initial test to clear that the pedal moves will not work on our year which is why the fuse test came up. I only noticed one fuse in the lower dash that had the ecm/?? letters associated with it and pulled it, never tried turning the key on to test it that way. Maybe I can get off work a bit early tomorrow to try that. I'm ready to pull all of them just for S & G to see if it will help. I believe you are correct about the fuse block under the hood but have not had a chance to check but that thought had crossed my mind as well.
 
midniteplowboyy said:
I was just thinking about you.

Pretty sure the brake pedal trick wont work on our trucks.




Edit, just looked at my wiring diagram. Constant 12v comes in on "A12" @ the TCM, it looks like it has a fusible link tied to the power distribution block.

You could unhook it @ the P-block or unhook the batts(pain in the Arse). You could also put a toggle switch on that "A12" wire if you didn't mind splicing one in, that would cut down on parasitic loss while the truck was parked for long periods also.
Click to expand...

I might just pull the batt cables this weekend if we don't get the snow they are talking about. That may be the easiest and quickest way to check the codes again. As for sitting for long periods,,,,only when shes down. When I'm working and driving her, I usually put 50 to 100 miles per day on her. Part of the reason I went to Amsoil as I was tired of changing the oil so often... lol
 
Think it would be easier to disconnect at the power distribution block. Do you know anyone with an old snap-on scanner you can borrow, it'll clear your codes and it would help you find your problem.
 
midniteplowboyy said:
Think it would be easier to disconnect at the power distribution block. Do you know anyone with an old snap-on scanner you can borrow, it'll clear your codes and it would help you find your problem.
Click to expand...
Unfortunately not. I wish I did but I'm more in the the "if your home breaks, I can fix it" mode rather than the automotive field. I do what I can to some aspect but in all reality, it scares the crap out of me. I don't like to screw things up, especially in my money maker. I always look at the situation that it is cheaper to have the right person fix it when they know what they are doing as I know, I charge extra for having to go in and fix someone elses screw-ups.
I'll probably just pull the battery cables, that way I can properly repair the wires that were improperly spliced by either GMC or the tranny shop.
Hopefully this weekend but may not be as I may have to work a bit longer on Saturday due to extra trips in my little back up Ranger.

Mark
 
5/16 wrench 1 bolt passenger side positive bat wire. Watch the underhood light when it goes off stop loosening the bolt. Wait 10 seconds and tighten the bolt back up.

Cake and the bolt doesn't come out. Fusible links are fragile at this age.
 
Evening gents,Just a quick update: I pulled all cables off the batteries today since I had a little bit of daylight left and some 40 degree weather and cleared codes.I checked them prior to starting it and then after driving it. No codes yet. I have not taken her on the highway yet but will try to tomorrow when we are supposed to hit 44 degrees to see if I have OD. Fingers crossed. I checked the other blue wire on the back of the tcm while batts were disconnected and they had a better splice than the blue wire from the tps. I resealed it and plugged the harnesses back in then reconnected the batts. Started her up(after checking for codes) and then tooke her for a ride. Checked for codes after the ride and still none. I did cloud a street on the way down to the gas station to add some fuel. I do need to get used to the new tranny as I had the high energy rebuild set installed as well as the triple disk converter. It seems to make a difference when shifting. It will shift differently when hard on the pedal and different when driving normally. Shifts on higher rpm when dropping the hammer. She shifts smooth both ways, just at different times. I would assume the shift kit has something to do with that as well. I hope and pray that this has solved the issue and once I clean and check all the grounds, she will be good to go for a long time again. I just need to get the IP turned up and install the FTB to get more fuel.Thank you for all of your help and I will keep you posted on tomorrows test drive. Mark
 
Glad you got it going. Atleast it aint so bad when you lose OD with the 3.42 gears, just a little slower than the 4.10 guys in OD.

When I was getting DTC68 I still had 4.10's, that sucks, I left my snap-on scanner plugged in for three months so I could clear the code when it tripped while driving.
 
midniteplowboyy said:
Glad you got it going. Atleast it aint so bad when you lose OD with the 3.42 gears, just a little slower than the 4.10 guys in OD.

When I was getting DTC68 I still had 4.10's, that sucks, I left my snap-on scanner plugged in for three months so I could clear the code when it tripped while driving.
Click to expand...

Thanks but no excitement yet. It runs fine in D and the tach rolls down when letting off the pedal like it should but still no OD and when driven in the OD mode the tach will just fall to idle as soon as I let off no matter the speed I'm travleing.I'm just frustrated and pulled the 68 again after being on the highway for one exit run with the same issue from the beginning, no OD and high RPMs.I just need to get my head out of it for the weekend. I just made life harder on my Ranger wreck as I needed to finish a debris hauling job tomorrow in the snow and it would have been nice to have my baby back. (frustrated!)
 
kimagine said:
Thanks but no excitement yet. It runs fine in D and the tach rolls down when letting off the pedal like it should but still no OD and when driven in the OD mode the tach will just fall to idle as soon as I let off no matter the speed I'm travleing.I'm just frustrated and pulled the 68 again after being on the highway for one exit run with the same issue from the beginning, no OD and high RPMs.I just need to get my head out of it for the weekend. I just made life harder on my Ranger wreck as I needed to finish a debris hauling job tomorrow in the snow and it would have been nice to have my baby back. (frustrated!)
Click to expand...

Oh heck, I quoted the wrong post you sent but, I believe you understand my point. Sorry about that....Have a great weekend.Mark
 
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