4wd randomly engages

gmtech4 · March 15, 2014

To be honest, it costs me less than half to replace the encoder ring than it is to have it scanned by a dealer. If I am wrong, then I still saved $55, since it can only be one other thing.

On the other hand, I refuse to pay $100 to simply find out what's broken on my vehicle. There is no reason with todays technology that you should need a multi-thousand dollar calculator to recieve system errors/faults. Not only that, but it allows mechanics to falsley state what is wrong with your vehicle. rather than you knowing directly before you visit. It really should be illegal in this day and age.

Imagine if Microsoft or Apple charged you $100 to display error codes on your computer or phone. There would be riots.

what tech would rip you off knowingly,,?,you got some clowns where you are then risking there jobs in some hill billy shops lol

as i said before telling a tech what to do because you found it on the internet is hilarious and dumb ,,,,,it takes all the countability out of the equation ,,,,,if it doesnt fix it its on you not them ,,,

"change my clutch ,its no good ,",,,,,tech says "so its the hydraulic slave cyl ,ya still want a new clutch "?

slippery slope is my opinion on that way of thinking thats all,

what ever floats your boat i guess

jcoast · March 16, 2014

Does anyone know how much the transfer case shift shaft turns or what direction to get into neutral? Is it a full turn or a fraction of one? I could not get it into neutral with the pushbuttons, so I replaced the encoder with it in 2-HI. Although, I did not have to turn the new encoder at all to make it fit in place of the old one, so I'm not sure if it's necessary to put the case in neutral.

Anyone I still have the same issue switching between modes, but I'm not sure if it will still randomly switch when driving with the new encoder.

Swamprelic · January 2, 2023

On 3/14/2014 at 8:04 PM, gmtech4 said:

what tech would rip you off knowingly,,?,you got some clowns where you are then risking there jobs in some hill billy shops lol

as i said before telling a tech what to do because you found it on the internet is hilarious and dumb ,,,,,it takes all the countability out of the equation ,,,,,if it doesnt fix it its on you not them ,,,

"change my clutch ,its no good ,",,,,,tech says "so its the hydraulic slave cyl ,ya still want a new clutch "?

slippery slope is my opinion on that way of thinking thats all,

what ever floats your boat i guess

Many many of them out there! More like what tech could you trust to get honest answer from!!!

StuSta · January 3, 2023

All of mine have done this at some point. I've found it helps myself to figure out if it's the actuator getting stubborn/sticky, or if the shift motor is a td unlocked or becoming defective.

What I do when it feels like the steering wheel wants to turn the rest of the way when turning slowly, or when you notice that odd wobble and sensitivity in the steering related to the room of the wheels, or worst casw when you hear a whirring sound and the front end shimmys super wildly and things become scary fast( motor mount that shares a connection with the front diff)

Couple things to try if it just doesn't feel right .

Put it into neutral, foot on brake and hold the 2wd and 4lo buttons simultaneously down for 10 or so seconds until the little red neutral I indictator light goes on. Gently shift to drive or re erase and it should not catch at all. DO NOT SHIFT TO PARK, if you are doing this with vehicle on, can so it with it off to but will most likely have to start it to know if it's truly clocked j to neutral. I've found that sometimes the force needed to rotate the shift shaft isn't quite enough by the encoder motor a d sometimes this results in the buttons flashing or not indicating a switch over although you felt or hear what sounded as such. Maybe a weak ground, weak battery+ idk but when you find it is not in neutral it is a sign that it wasn't where it was supposed to be, this is true often because neutral is easier to engage then going from 4lo to 2wd etc. I also find this occurs more often when using 4auto .

I've also found that reversing a few miles per hour then dropping trans into neutra while still rolling seems to help effectuate a shift between 4lo and 2hi vice versa.

Also yes of course, I've seen where the solder on the small pc board behind the buttons actually separates from itself on the rear portion it looks like the solder cracks apart essentially, not a difficult fix either .

Lastly if your doing an encoder motor. Do not, do NOT press the buttons or activate a shift with the motor not mated to the t/c. Just don't. Also before you pull the encoder motor, make certain to put it in the gear position that the new one comes in. Also it's often not a whole encoder deal that has failed. The small seal can fail and atf/gear oil gets into the small dial with the contacts and makes it pretty lame most times. One can replace a small portion of a motor jf this happens rather than dishing out a s putting a lesser quality aftermarket version all because of a seal failure etc.

I hope this helps . Also remember bolts come loose and alignment is important with engine/trans/trans case, as is that aluminum cast t.c. adapter that likes to crack over and over on so e trucks... Motor mounts trans mounts and tranny leaks are the 3 that you don't want to delay on or you may end up finding that it could lead to utter demise, dominoes effect etc. I have a 4x4 4l80e to deal with now because of a small tree stump dent on big 1 piece aluminum/s shook the bolts out of the bell housing . Ouch ! Took the case first then the trans when it happened again. Life's not quite been as grand since..

I hope this helps someone someday as it took me many years to feel l Understand how to keep an upper hand on these. These are peculiar trucks but once you deal with the same problem a few times on a few of them, you start to remember what it actually needs .

Edited January 3, 2023 by StuSta