So I recently had a local guy build up my transmission with the Suncoast gmax 3 and I had him replace almost everything else in the process. We got the trans back in and started it up and it's now throwing codes p0751 p0843 and p0877 while it's in park. When shifted it then throws codes p0761 and p0762. However all the solenoids are new as well as the pressure switch. Anyone have any ideas. I thought about getting a new tcm bc I'm not sure what else to try at this Point
New Suncoast build throwing codes p0751, p0843, p0877
- Thread starter Alaney
- Start date
Don't you think you should try and fix your trans before you start giving others advice?
Man, you guys can get catty here... lol.
Was anything I said out of line? I'm just trying to be helpful, since I've done a lot of research this topic recently. Suggesting looking for clues in the wiring and fluid seems like a relatively benign thing to do.
I like cats.
Now that you've shared your new found research on the subject; what are you going to tell him to do next?
Now that you've shared your new found research on the subject; what are you going to tell him to do next?
Well, after that, I probably would have said "maybe Mike L will chime in"...
The obvious thing is to take it back to the builder, but if he wanted to do that, he wouldn't have asked for help.
If you twisted my arm, and made me show my ignorance... I would say that it's odd that it is saying a valve is stuck closed and open at the same time. That's what makes me think it could be electrical (or maybe some leaking between passages in the vb).
So, my logic would flow like this:
If the external harness and nsbu check out, I would say check the fluid level. If that's okay, take the pan off and check that the internal filter is still in place, there are no problems with the internal harness, the new psa operates correctly, and the new solenoids ohm out correctly.
If there's junk in the pan already, it's likely there are really stuck valves. In which case, the builder probably did something(s) wrong.
If everything looks okay, I'd suggest removing the vb, cleaning everything, checking the fit of all the valves, and checking the halves for straightness. Also make sure everything was assembled correctly.
If it's none of that, then I would consider the TCM swap... I guess you could do that before pulling the pan, and return the TCM if it didn't help. I just don't think it fits with the story.
Edit: after reading back through that, it is pretty general, and could probably be used to diagnose almost any valve body related codes... but that's what you get when you ask someone without years of experience with the allison.
The obvious thing is to take it back to the builder, but if he wanted to do that, he wouldn't have asked for help.
If you twisted my arm, and made me show my ignorance... I would say that it's odd that it is saying a valve is stuck closed and open at the same time. That's what makes me think it could be electrical (or maybe some leaking between passages in the vb).
So, my logic would flow like this:
If the external harness and nsbu check out, I would say check the fluid level. If that's okay, take the pan off and check that the internal filter is still in place, there are no problems with the internal harness, the new psa operates correctly, and the new solenoids ohm out correctly.
If there's junk in the pan already, it's likely there are really stuck valves. In which case, the builder probably did something(s) wrong.
If everything looks okay, I'd suggest removing the vb, cleaning everything, checking the fit of all the valves, and checking the halves for straightness. Also make sure everything was assembled correctly.
If it's none of that, then I would consider the TCM swap... I guess you could do that before pulling the pan, and return the TCM if it didn't help. I just don't think it fits with the story.
Edit: after reading back through that, it is pretty general, and could probably be used to diagnose almost any valve body related codes... but that's what you get when you ask someone without years of experience with the allison.
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Come on... you gotta tell me if I was close...I like cats.
Now that you've shared your new found research on the subject; what are you going to tell him to do next?
What's the worst that could happen? Mike L responds and makes me look like a fool? I'm okay with that; at least I will have learned something.
If this were real life, we would probably all be sharing some beers having a productive conversation, and probably slinging a lot of bullshit, but because it's the Internet everyone takes everything way too seriously.
I wish i could help ya bud but im still learning too. I'd say you have a internal issue. My question is, you paid some someone to build it and they cant figure it out? They shouldn't be calling themselves a builder... I get that everyone has to start somewhere but your customer shouldn't have to be on the forums trying to figure out whats wrong, if anything he should be on here asking.
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I do not want anyone to look like a fool. When I have questions or needs, I do some research and hire a professional to do what I can't do. I know what my limitations are.
This is real life and people need some answers. I realize that you want to help, but you haven't fixed your own trans yet.
Fix your trans and come back here and we will take you more seriously. What you posted was right out of the Allison book. That's fine, but remember the tests start now after what you posted. After some ones so called build ( clutch pack not a build ); we have no idea what was or wasn't done properly and all the printed tests fly out the window. There are no codes for installing something wrong. Most of the new guys here installed kits themselves and will not admit it and want answers. No help for that.
Very well said. I know you guys probably get jaded by all the new folks showing up asking questions about some mysterious codes on a trans from a no name 'builder'.
I certainly don't mean to intrude or rub anyone the wrong way... was just trying to help field some of the easier up front diagnosis suggestions. I will refrain from doing so.
I think I've derailed OPs post pretty badly, though. Any news on the problem?