What else can go wrong. Range shift inhibited

[03spoolindmax]

Well it's been pretty cold here in michigan lately. For the past few weeks trans has been acting funny. It started. About 2 weeks ago when I left my house to go to work. 2-3 and 4-5 shifts will feel like there going into neutral between shifts. It did it for about a day or two the. Went away and was shifting perfect. Until yesterday it started to do it again and then would go away. I stopped by hsp to check the progress on my twin kit and when I left I put it into reverse and it felt kind of funny. Put it in drive and it was stuck in 3rd gear. Pulled into a parking lot and hooked up the scanner. I can't remember the code off the top of my head but I believe it had to do with solenoid b. I cleared the code. I put the truck in neutral and high idled it to help warm it up. Put it into gear and trans was fine. The 2-3 and 4-5 shift flare was back but went away by the time I got to work. Went to leave work and let it run for about 10 minutes. Put it in reverse and it was fine. Put it in drive and it also went into gear. Went to pull out and started driving. Put it In 4wd and went to take off and it felt like it was in neutral. Put it back in 2wd and it was stuck in 3rd gear. So I pulled off into a lot to check it out. Hooked up the scanner and had an incorrect 3rd gear ratio code. Shut the truck off and restarted. When putting it In reverse or drive truck felt like it would go into gear but would not move. Range shift inhibited kept popping up. Got under the truck and saw some fluid on the ground near the driver side coming from above the NSBU switch. It has never leaked until now. Checked fluid level and it was fine. After about a half hour I decided to play around with 4wd. Shifted into 4 lo and got the truck to finally move. Put it back in 2wd and limped it home.

Now here's the info on the trans. I built it about 2.5 years ago. Has a gmax 5 kit and MLG converter. Has around 30k on it and has shifted great until about 2 weeks ago when it got really cold. The trans was originally in my 03 and now is in my 05. Truck is stock with no programmer just has the built trans. Sorry for the long post. I just wanted to give as much info as possible. I'm going to dig into it more in the morning and see if I can pull some codes out of it.

 

[Kappa9012]

is this a different truck thank your signature??? probably need to see what the codes are

 

[03spoolindmax]

Same truck as sig just haven't installed the twin kit or got the tunes yet. Like I had mentioned it had an incorrect 3rd gear ratio and a solenoid b code. Both codes were at different times but not together. It happened kind of fast and I didn't have time to write them down. Cops showed up and thought I was breaking into a place :roflmao: until he found out I work for the city and fix his car. Then he was cool and chatted with me for a few.

 

[03spoolindmax]

Just went out to the truck and pulled the codes. It now has an p0731 incorrect 1st gear ratio and p0746 pressure control solenoid a performance/stuff off. Every time it throws codes it's always something different.

 

[03spoolindmax]

Cleared the codes and took it for a ride. Had 1st and 2nd then went to neutral when trying to shift into 3rd. Locked in 3rd as limp mode. Pulled the codes again and had p0746 pop back up. I'm going to check the fluid level in the morning and see where it's at. Not what I had planned on dealing with this weekend.

 

[TheBac]

Yeah, dealing with anything outside the last few weeks has been, um, interesting....to say the least. Thick fluid flow in low temps would be my guess.

 

[Mike L.]

I would be looking at a transfer case problem or speed sensor problem. It is rare for the Allison to throw a P0731 code which would indicate bad C1 clutches or TC neutralizing on take off. What ever the malfunction is; it's happening in different gears and different times and that's why you are seeing different codes.

 

[03spoolindmax]

Thanks mike for the input. Ill dig into it and see what I can find. I find it hard to believe I toasted a built trans in a stock truck while driving normal.

 

[03spoolindmax]

Well I started the truck and let it idle in neutral for a little bit checked the fluid and it was low. Added about 2 quarts and let it warm up. Drove it around the block and shifted great. Right before I get it. Bam truck goes into neutral and then locks itself in what seemed like 4th or 5th. Was very sluggish and couldn't get Rpms to go past 1200. Got it home and hooked up the scanner. Now it's throwing p0733 incorrect 3rd gear ratio. I'm going to get it in the garage here shortly and check into the t case like mike had mentioned.

 

[03spoolindmax]

Had some things to take care of so didn't get a chance to dig into the problem. I'm gonna get a new spin on filter and also drop the pan tomorrow and check it out. I'll also inspect the tcase, sensor & reluctor wheel. If I can't find anything I guess I'll be calling mike Monday about a new trans kit. First head gaskets go this week and now this. By the time I'm finished ill basically have a new truck :roflmao:

 

[03spoolindmax]

Got a chance to look at the truck. Removed the spin on filter and fluid looked brand new. Magnet had a very slight amount of material on it and that's it. Could see trans fluid leaking from on top of the trans. Looked to be coming from the vent. Cleaned it all off. Removed the NSBU switch which was covered in fluid cleaned it off and cleaned off the connector also. Removed the rear output speed sensor and checked the reluctor wheel. No play in the wheel and drive shaft going into t case was tight with no play. Put in a new speed sensor. Checked fluid level and took it for a drive. It went into gear but still felt like it was going into neutral between the 2-3 shift. Was able to get it to 4th gear once. Just decided to park it. Starting to seem like bad c3 clutches. I'm just gonna pick up a local stock trans and replace it for now. Then tear into this trans and find out what's going on.

 

[1brokekid]

Mine did this, especially when it was cold, but it was just low on fluid. Mine leaked from the cooler, replaced that and now I have no issues.


Sent from my iPhone using Tapatalk

 

[03spoolindmax]

Mine doesn't have any leaks. I'm pretty sure I fried the c3 clutches. I'll find out when I take it apart.

 

[Mike L.]

Mine doesn't have any leaks. I'm pretty sure I fried the c3 clutches. I'll find out when I take it apart.

Look further. Never seen bad C3 code P0731. Bad C1, plugged internal filter, or transfer case.

 

[03spoolindmax]

I replaced internal and external filters. NSBU and ignition switch. When I dropped the pan everything looked good with slight clutch material but nothing excessive. Only code I get now is p0746 solenoid a performance stuck off. Seems to only act up and shift flare on a 2-3 and 4-5 shift and same with a 4-3 downshift. If I throttle it while in the middle of a downshift it'll throw the code sometimes. Only thing is other times it'll shift perfect. I did remove the connector off the back off the trans. Saw slight trans fluid in it. Sprayed it off and used dielectric grease. It was late at night and the Allision dealer wasn't open to get a new internal harness or I would of replaced it.