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H3 in limp mode AND stuck in 4HI after tcase shiftfork, range fork, shift rod rplcmt
Hummer H3For the Hummer driver who wants the rugged look and off road capabilities of the Hummer, but in a smaller size and with a more fuel economy friendly engine.
H3 in limp mode AND stuck in 4HI after tcase shiftfork, range fork, shift rod rplcmt
H3 in limp mode AND stuck in 4HI after tcase shiftfork, range fork, shift rod rplcmt
Hey guys. I have a 2007 H3 hummer I just replaced the transfer case plastic to metal shift forks, the range fork and shift rod inside the tcase. After putting the tcase back on and then the encoder motor and battery, the hummer is now in limp mode. It’s also stuck in 4HI and won’t go into 4HI lock or 4LO. Any suggestions of where to start troubleshooting this? Do you guys think it’s the encoder motor that now needs replaced or is it something like I need to fry out the ecm or clean the TB or something. Any and all sugg appreciated. Thanks!
Are we to assume you did the work correctly and kept all the Planetary Gear marks lined up if you pulled the gears?
To do the basic shift fork replacement, the culprit is the Lock Shift Fork (not the Hi/Lo Fork) and you can replace that keeping all the gears in place. Example leave the gears alone thread by CWC Goodbye plastic
Are we to assume you did the work correctly and kept all the Planetary Gear marks lined up if you pulled the gears?
To do the basic shift fork replacement, the culprit is the Lock Shift Fork (not the Hi/Lo Fork) and you can replace that keeping all the gears in place. Example leave the gears alone thread by CWC Goodbye plastic
This unfortunately was not a basic shift fork replacement. There was extensive damage done by a body shop that didn’t know what they were doing when putting on an encoder motor for me and broke several parts inside the tcase. However, we went through it with a fine tooth comb and replaced whatever needed replacing. All the gears were obviously lined up and we made sure everything worked properly inside the tcase before even putting it back on the hummer. This is the first time the hummer has gone into gear since it originally broke down a while ago. It took us a ton of work and time and money which is why it’s been a while but now it just goes into limp mode when turned on. I never replaced the encoder motor again after the shop replaced it and I’m wondering if bc they put the encoder motor on when it wasn’t the encoder motor and it was the shift fork if the tcase destroyed that encoder motor that’s on it even though it was a new encoder motor bc the shift fork issue hadn’t been rectified yet….
To diagnose the shift encoder motor remove from Tcase, leave plugged in and see if it will change position.
If it works, then your issue is the Tcase internals.
The encoder motor just turns a square peg to the degree you select with the dash T Case buttons. You could try a new one if you want, but I would test the current one and its harness connector. Easy stuff first.
Never heard of the plastic shift fork doing any damage other than failing to function, ie. deflect or jump out of slide collar grove.
If the timing marks on the planetary gears are not lined up, you will have issues similar to yours......... or worse.
H3 in limp mode AND stuck in 4HI after tcase shiftfork, range fork, shift rod rplcmt
Originally Posted by DrSatanPro
This unfortunately was not a basic shift fork replacement. There was extensive damage done by a body shop that didn’t know what they were doing when putting on an encoder motor for me and broke several parts inside the tcase. However, we went through it with a fine tooth comb and replaced whatever needed replacing. All the gears were obviously lined up and we made sure everything worked properly inside the tcase before even putting it back on the hummer. This is the first time the hummer has gone into gear since it originally broke down a while ago. It took us a ton of work and time and money which is why it’s been a while but now it just goes into limp mode when turned on. I never replaced the encoder motor again after the shop replaced it and I’m wondering if bc they put the encoder motor on when it wasn’t the encoder motor and it was the shift fork if the tcase destroyed that encoder motor that’s on it even though it was a new encoder motor bc the shift fork issue hadn’t been rectified yet….
Bu11Fvk'nSh!t! ONLY 1 Way to install the encoder motor!
"Limp mode" would not be caused by a transfer case error, stab sys on the dash could cause it.
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Answers for Frequently Asked Questions on Functions:
No codes are being thrown zero zip. That’s why I’m so confused.
You may need a better scanner that will read ABS fault codes.
Every time I have seen STABSYS faults it has been ABS related. With an ABS related fault you are not able to switch Tcase modes unless you do it manually.
H3 in limp mode AND stuck in 4HI after tcase shiftfork, range fork, shift rod rplcmt
