Help!!! Fixing to have a blaze in my driveway

[Mike]

Mike L, I am getting a P0872 code continuously. I have checked "E" shift valve repeatedly, and the valve has not been stuck and moves freely each time I checked it. I have replaced E " on/off " shift solenoid and checked to make sure the psm is functional.

Should I check the C1 clutch pack? But then again, 3rd is working?????? I guess if limp mode 3rd is working.

This all came about after reinstalling the transmission after checking the flex plate. All was fine, but just had to do extra work for nothing.

Is there any chance the truck limps to 4th? If I drive the truck in limp mode, the truck rpm's reflect the same rpm's the truck showed while in 4th when the transmission was functional.

Thanks you.

 

[Mike]

If the truck is limping to 4th, this is the same thing that was happening that caused me to have my transmission rebuilt. Hmm.....

 

[duramaxin14]

O i pray someone can shine light on this i have the same exact problem. pulled tranny pan back off put new solenoids in it and still doing it

 

[Mike]

O i pray someone can shine light on this i have the same exact problem. pulled tranny pan back off put new solenoids in it and still doing it

Did you install the solenoid in the center spot in the valve body?

 

[duramaxin14]

not sure mike all i no is ever solenoid a allision has in the vb there all new

 

[BIG DIPPER]

It is the shift valve guys. I know it is hard to believe as it is free on the bench, but the valve sticks again after the valve body twists from being torqued.

 

[duramaxin14]

Big dipper if they are not sticking on the bench then how do u suggest not to get them to stick in the tranny clean the hole that there in or what? Also is the e shift vavle the long rod with the link pin on it that goes to your gear selector?? Also im not trying to be a smart ass so please forgive me if it sounds this way. I am just fed up with this shit and ready to light a macth to the truck.

 

[Mike]

Big dipper if they are not sticking on the bench then how do u suggest not to get them to stick in the tranny clean the hole that there in or what? Also is the e shift vavle the long rod with the link pin on it that goes to your gear selector?? Also im not trying to be a smart ass so please forgive me if it sounds this way. I am just fed up with this shit and ready to light a macth to the truck.

Kurt, I'll email you a picture from ALLDATA I have downloaded. It will have what you should check for.

 

[BIG DIPPER]

It twists when it gets torqued down.....think of honing an engine block and the use of torque plates whil doing it, same thinking applies here.

Actually, it has been claimed as a casting flaw. I have seen some do it and some don't although I now hone the bore on every trans I do.

 

[Mike]

It twists when it gets torqued down.....think of honing an engine block and the use of torque plates whil doing it, same thinking applies here.

Actually, it has been claimed as a casting flaw. I have seen some do it and some don't although I now hone the bore on every trans I do.

I have about every tool I don't need, but I wish I had a tool that I could use as a hone in a bore that small. I'll pull the pan and valve body again here in a minute and give it another shot. Thanks for the help, I do appreciate the advice. On one of the last checks, I even swapped the " E " and " D " on/off solenoids. Why is the trans taking off in 4th? Thanks again.

 

[BIG DIPPER]

Change the spin on. If it clears up after that, cut the filter open and have a look inside it.

 

[Mike]

Check your email Kurt.

 

[duramaxin14]

thanks new lb7 for the email. let me know if the e shit honning deal works out for you because i may be doing the same deal i dont believe the soionid screen would have anything to with it but well see thatnks again man

 

[LB7Diesel]

Might try a pencil wraped with some fine grit sand paper..Or grab the scrubby out of the kitchen sink and use the brillo stuff wraped around the pencil fit to size..Kinda like starting a fire Indian style..Just throwing out ideas, I've been drinking too so you might want to come up with your own idea!!

 

[Mike]

Might try a pencil wraped with some fine grit sand paper..Or grab the scrubby out of the kitchen sink and use the brillo stuff wraped around the pencil fit to size..Kinda like starting a fire Indian style..Just throwing out ideas, I've been drinking too so you might want to come up with your own idea!!

Thanks, I appreciate the thought and idea. I'm up for anything. Guess I'll have to invent a manual valve body for this darn thing. That's an idea

 

[Mike L.]

How tight are you guys torquing these things? They should not be any tighter than you can tighten with a nut driver. Valvebody must be clean; your hands must be clean and the valve must be clean. This shit is like surgery. All the bolts on the VB should be hand tight when bolted up to case then all bolts should be torqued on the case. P0872 can also mean a short in wiring harness or pinched wire going to trans.

 

[LBZ]

Mike (new2LB7) as you never took your valve body apart (right?) I would lean towards the harness too. 1 shorted wire or a pin that is bent or moves back in the plug when you plug it in can cause nightmares. You need to push and pull EVERY wire in EVERY plug to ensure this isn't the problem.

I've had it happen to me before in an ecm harness plug once - took forever to find it.

 

[duramaxin14]

mike that was my brother on earlier i figure u would no because he was calling u new 2 thanks for the info i will tear the vb down tommorw

 

[Mike]

How tight are you guys torquing these things? They should not be any tighter than you can tighten with a nut driver. Valvebody must be clean; your hands must be clean and the valve must be clean. This shit is like surgery. All the bolts on the VB should be hand tight when bolted up to case then all bolts should be torqued on the case. P0872 can also mean a short in wiring harness or pinched wire going to trans.

Thanks Mike L. I'll keep the tightening technique in mind. I could most definitely be guilty of over torquing the valve body, 109in/lbs is not a lot. Everything is very clean, including my hands and tools. I have gone through the steps, listed for this P0872 code, provided by ALLDATA concerning the shorted wiring. I'm up for anything and will certainly take you advice and use it. Thanks.

 

[Mike]

Mike (new2LB7) as you never took your valve body apart (right?) I would lean towards the harness too. 1 shorted wire or a pin that is bent or moves back in the plug when you plug it in can cause nightmares. You need to push and pull EVERY wire in EVERY plug to ensure this isn't the problem.

I've had it happen to me before in an ecm harness plug once - took forever to find it.

Yes, you are right Dale, I started having this trouble before I removed the valve body. I only removed the valve body to go through the trouble shooting steps provided by ALLDATA. I will certainly check the wiring. I checked the plugs when I bypassed the co-pilot wiring and did not find any bent pins, but will recheck.

Thanks Dale.