transfer case acting up!

[dirty anton]

having some weird issues with transfer case. while on a trip to the green ridge forest last week in 4 lo james d noticed the front wheels wouldn't grab.but when the front end came off the ground, the front wheel would spin then not grab when back on the ground. could not get up a rocky hill. then i put it in auto and it crawled right on up no problem. also when getting in truck after it sits a while, i turn on truck and the transfer case puts itself in neutral, and i have to set it back to 2 wheel drive to go....now things i have done recently: i have replaced all fluids in late summer,transfer case, both diffs, and just rebuilt front disconnect (every thing looked good just replaced bearings and seals). any ideas?.....thanx.

[Trail X]

Now that I think about it, it's possible that your encoder motor lockout has failed. It's an electronic clutch that locks the encoder motor in place. It's possible that, for instance, it's locking 4WD into the proper location, but the lock is not engaging, so the encoder motor is just slipping out of hard lock (I don't believe it's readjusted after being set).

Or your clutches are toast - but that doesn't really explain the Neutral thing - the encoder clutch possibly explains that.

Otherwise, very confusing.

You did say that you have a new TCCM, right?

[dirty anton]

yea a new tccm as of last spring and a clean bill of health from a chevy dealer where a friend of a friend works. took the truck to them last year because tc was going to neutral while driving. dealer said there was a short in wiring said was fixed, now the tc does the neutral shift when starting after a long break. just trying to avoid the dealer if i can, but have never pulled apart a tc.

[Trail X]

The encoder and encoder lock are external to the case and can be pulled without opening the case.

Have you read through the following article? Transfer Case Tech: The NVG 226 (NP8) Theory of Operation
It may not solve your issue, but it does clear up the operation of the case, which might help you locate the issue.

[dirty anton]

yea i have read that several times, good read! i just may have to pull the encoder and check it out.

[Trail X]

http://forums.trailvoy.com/showthread.p ... se+neutral

Sounds similar, if you can get past the terrible posting grammar and spelling. See the last post - he said his encoder motor brake went bad and wouldn't hold the pressure on the clutches. I believe that's your issue. Could still be wrong.

[dirty anton]

wow does sound very similar! also what Roadie said was spot on as far as wheel spin in air vs on ground. deffinatly going to pull motor and see what can of worms pops out! thanks for the research james i have bin googling it all morning and only finding partial info.

[dirty anton]

well i replaced the transfer case shifter motor and the problems gone!! 4 wheel is back!! and the neutral shifting on its own is gone!! easier than installing an alternator. 4 bolts and an electrical harness. fingers crossed this is it! found one on ebay made by dorman 162 shipped. i guess these wear out enough for outside companies to manufacture them. glad cause chevy wants way way more for this. thanx again james and everyone this site is a wealth of info. has saved me a whole lot!

[Mooseknuckle]

Nice! all is still good?

[dirty anton]

yea everything is working great! the neutral problem was here and there for about a year then recently almost everytime i would start the truck. past couple days(since replacing the shifter motor) has bin acting normal. no issues at all! thanx for asking!

[Mooseknuckle]

Good I'm glad its back to normal working condition.