02 ccsb 4x4 lb7 only mods is pretty much the ppe xcelerator. Truck will run fine and shift smooth then out of nowhere not even driving it hard get stuck in 3rd gear, will not shift down from 3rd or up. The shift indicator doesn't blink or anything, reverse still works. Usually when it does it I can just reset the trans with the ppe then get back to Rollin and it does fine, today going to work when I started the truck it was stuck in third, and I tried resetting the trans, and put it back to stock tuning, and still stuck in 3rd, cycled key on and off several times and still stuck so I drove to work doing 30mph then when I left work it shifted through every gear fine. What is this??
Lb7 limp mode or...
- Thread starter BrystonLb7
- Start date
Time to look at getting the tranny rebuild.. How many miles is on it.maybe this post is nicer
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I think your trans is toast, how long have you had the ppe on the truck and on what tune have you been running it?
Aright thanks I was just trying to make sure it wasn't the NSBU or solenoid or a valve sticking before I rebuild it. 288k on the truck, had the ppe on for about 3k miles and ran it mostly on the 90 horse tune sometimes the 120. But gee now I know who's kit I won't be buying!
Aright thanks I was just trying to make sure it wasn't the NSBU or solenoid or a valve sticking before I rebuild it. 288k on the truck, had the ppe on for about 3k miles and ran it mostly on the 90 horse tune sometimes the 120. But gee now I know who's kit I won't be buying!
Wishful thinking
If it's been said 100 times its been said a 1000 times that anything at or near an additional 100 HP added to the Allison transmission in stock condition will result in slipping clutches and the lose of 5 th gear and limping the transmission. That is why some throw a little sarcasm out as everyone should know by now.
Had the same thing happen to me on the highway. stuck in 4th and shut it off and it ran fine but would go into limp mode if I used level 5. I was told that too much slip in the torque converter will do this to protect tranny and will start to slip easier and easier every time However I just knew that too much torque would do this so I don't go past level 3 no more till I build a new tranny. Hope this helps and don't quote me I'm no expert just telling you of my experience and since then I used level 3 on edge juice w/attitude no more limp mode.
Anyone tell me what this is in the tranny? I got another used one so I can save up to build mine, should I go ahead and upgrade the torque converter when putting the new one in or is that not something that usually goes out in these?
Yes you should replace the Tq. converter. You should also flush the cooler lines and cooler before putting it back together.
If the trans is slipping (code such as P0735), then your clutches are toast. Its the clutch packs inside the trans.
When your trans gets built better clutchpacks are installed along with mods to increase pressure to them. There are some other things as well that each builder does on their own like the super secret turbo encabulator mod, or the Mike L. canuter valve shim, but the main thing is better clutch packs and more pressure.
Yes you will want an upgraded converter and as the other Mike said make sure to flush the lines.
The slip is usually in the clutch packs not in the converter lockup clutch. But yes limp home can be a protection mode triggered by many things, one of them being "Incorrect Gear Ratio" aka slip.
To clarify, my trans is toast, so I bought a used tranny in good shape to put in it, and was wondering if before i put the new one in if it'll be worth it to go ahead and upgrade the TC before installing and maybe a shift kit. Can't afford a full build right now
If you don't do anything this transmission will be toast also if you put the power to it . Do you know the history on this used unit? Might have wear already.
You should replace the TC anyway with a triple.If it were me and I could not afford a full build up I would at least put fresh clutches (stock from Allison) in it and a Transgo kit. Just don't turn the power up!
Aright thanks I was just trying to make sure it wasn't the NSBU or solenoid or a valve sticking before I rebuild it. 288k on the truck, had the ppe on for about 3k miles and ran it mostly on the 90 horse tune sometimes the 120. But gee now I know who's kit I won't be buying!
Come on man. Mike has helped countless people on here and other forums. You should know your trans can't take 120hp over stock!
I'm gonna try and skate the fine line on my 09, but I've already talked to mike and know what's, eventually going to happen.
You've got 288k on there, it's time for a full rebuild. How many miles on the used unit??
Seriously need some questions answered.
First I got the "new" used tranny in and it's throwing the code 0872 one ppe which I know is the E valve stuck code. And going straight from 1st when you start rolling to 3rd in about 3 feet. Limp. So I was planning on taking the valve body out of my old tranny and putting it in the "new" one. Should be okay right? And when getting the vb out the old tranny is it okay for the tranny to sit on the bell housing while removing or will something inside jack up of done that way?
And next. I ran the codes on my ppe and got the 0872 code. Then also ran codes with a bullydog I had sitting around and got the 0700 and 0872 codes. Limp and e valve. Anything to be worried about?
And lastly everytime I run the dtc's on my ppe it gives me the codes then keep scrolling and it starts giving alot of weird codes like, 484D, 5258, 5E64, 6A70, 767C, 8288, 8E94, 9aa0, A6ac and alot more. Any help is appreciated!! And sorry to
Mike L. Didnt know you were the allison god when I got on here thought you were just another smartass.
First I got the "new" used tranny in and it's throwing the code 0872 one ppe which I know is the E valve stuck code. And going straight from 1st when you start rolling to 3rd in about 3 feet. Limp. So I was planning on taking the valve body out of my old tranny and putting it in the "new" one. Should be okay right? And when getting the vb out the old tranny is it okay for the tranny to sit on the bell housing while removing or will something inside jack up of done that way?
And next. I ran the codes on my ppe and got the 0872 code. Then also ran codes with a bullydog I had sitting around and got the 0700 and 0872 codes. Limp and e valve. Anything to be worried about?
And lastly everytime I run the dtc's on my ppe it gives me the codes then keep scrolling and it starts giving alot of weird codes like, 484D, 5258, 5E64, 6A70, 767C, 8288, 8E94, 9aa0, A6ac and alot more. Any help is appreciated!! And sorry to
Mike L. Didnt know you were the allison god when I got on here thought you were just another smartass.
P0700 just means the TCM requested a MIL. Many cheap scanners pull that up but cant read the actual TCM codes. You can read up on the E shift valve sticking, lots of info out there on that topic.
Standing the trans on the bell housing and then removing valve body will not harm anything.
Sent from my SCH-R970 using Tapatalk
Standing the trans on the bell housing and then removing valve body will not harm anything.
Sent from my SCH-R970 using Tapatalk