Problem with 4wd

[Pitch22]

The other day I tried to use 4wd while driving in the snow. I turned the switch to 4wd and I can hear the high pitched motor noise but my front wheels r not engaging. However wen I use A4wd the front kicks in when I spin my back tires and then ill turn the switch to 4wd and the front wheels stay engaged. Also wen I turn it to 4wd and the front tires do not engage, I spin my back tires and I hear like a clicking or grinding noise coming from the front end. Does anybody know what the reason could be for my 4wd not working properly? Any input is appreciated. Thanks

[TBYODA]

First how many miles, year, maintenance history, etc? This will help us help you, more the veterans here than I.
Second with the TB off move the selector switch back and forth for 2wd to 4wLo about 100 times, this will clean the contacts in the switch to insure good signals are passing through. Are any flashing lights on the switch when you move it to different position, do you have service 4wd light on? IDK but from your discretion sounds like your disconnect could be damaged.

Required reading
http://www.offroadtb.com/articles/tech- ... wd-system/

http://www.offroadtb.com/articles/tech- ... isconnect/

http://www.offroadtb.com/articles/tech- ... operation/

[The Roadie]

Clicking is very often correlated with a disconnect collar problem.

[Pitch22]

Its a 2005 TB with 113000 mi. Iv never had any problems with it. 4wd worked great last winter and this is the first time iv tried it since last winter. There are no service 4wd lights on. Everything seems to be working fine but the front wheels just wont engage.

[Pitch22]

If its a disconnect problem about how much will it be to get it fixed?

[TBYODA]

If its a disconnect problem about how much will it be to get it fixed?

There are pretty pricy.

http://www.rockauto.com/catalog/x,carco ... type,14757

http://www.amazon.com/ATP-111001-Front- ... automotive

[Trail X]

Based on your description, I'll agree, disconnect - or - the encoder motor lock. Sometimes hard to tell. Check the tripod of the passenger side CV axle, and see if you can move it up or down in the housing. If you can move it more than 1/16", you might have a toasted disconnect. Aftermarket units can be had for around 250 if I recall correctly. One's made by ATP.

[Pitch22]

I forgot to mention. Sometimes, but very rarely, my front wheels do engage when I switch to 4wd. This is normally not the case though. If it were a disconnect problem would it still sometimes work? Or would it never work?

[Trail X]

There are various stages of disconnect degradation. Normally, it doesn't just all of the sudden stop working, because we aren't really breaking things. The wear is just severe, and over time it goes from intermittently working, to rarely working, to never working.

If you can, please read and then run through the flowchart on this page: http://www.offroadtb.com/articles/tech- ... wd-system/ The process generally helps us narrow down your issue. The key is understanding if the front driveshaft/propshaft is spinning with the front passenger side wheel or not.

[Pitch22]

Could the problem be the encoder motor? Im am hearing a high pitched noise but I think there is supposed to a lower pitched noise that im not hearing.

[The Roadie]

The lower pitched noise is very distinct because it happens in EVERY mode transition. The high pitched noise from the front axle actuator only happens in 2HI->A4WD and A4WD->2HI transitions. And you can change modes with the ignition on but the engine not running to make it easier to hear.

The encoder motor or its solenoid brake could have a problem, but almost always, the position feedback sensor will report a failure to move back to the TCCM, and then the target mode light flashes on the mode selector switch. (Target being the mode you're trying to change INTO.)

[Trail X]

Do the flowchart.

Bill, we've had a few of the locks fail, and that does not seem to report back to the TCCM when that slips. The issue is that the TCCM demands the position in 4WD mode, locks it down, and forgets about it. The motor then slips, and the TCCM doesn't notice. It's easy to diagnose this, because A4WD will work fine, but 4WD will not. At this point Dalton just needs to do the flowchart, and also listen near the transfer case with the engine off for the motor to spool.

[The Roadie]

The issue is that the TCCM demands the position in 4WD mode, locks it down, and forgets about it.

Well, it wouldn't forget about it if *I* had written the code.



Yah, I haven't had that failure yet, and I keep forgetting about those that do. Maybe somebody should update MY memory management code.

[TBYODA]

Well, it wouldn't forget about it if *I* had written the code.

Bill if you wrote the "code" the SUV would do not do a 1/10 of the of the dumb it does. That I have read about.

Maybe somebody should update MY memory management code.

hahahahahaha

[djthumper]

Maybe somebody should update MY memory management code.

I think those upgrade parts are End of Life.

[Pitch22]

So yesterday i got under my truck and tried to move the cv axle to see if my disconnect is bad. I couldn't get anything to move at all. I did notice a 360 degree spatter of grease around the rubber boot on the cv axle. This is on both the driver and passenger side. I did get my truck lifted about a month ago and from what iv read i think that is the reason for the grease. Would the leaking grease have anything to do with my 4wd not working properly?

[Trail X]

Not likely, but possibly. Did you run through the full 4wd diagnostic flowchart?

[DirtyBacon04]

I agree with James, i'd be hard pressed to believe that ,based off your description of the issue, it'd be related to grease slinging from CV. Pop open that disco and take a gander. take a big sniff, too. I'm sure it'll smell wonderful.

[Pitch22]

I took my truck in to get a wheel bearing changed and the mechanic said both the front wheels are hard to turn because of the angle the CV is at due to the lift. He also noticed the grease coming out of the cv boot. He said ill ruin the CV's if i don't lower it back down. He also said if the grease would stay in the boot it would be fine. What are some ways to seal the boot better so grease doesn't leak? Thanks alot for the help guys.

[Trail X]

4" hose clamp will seal it.