Help! 4wd will not engage

Hi everyone,

Sorry if this thread has already been created, but couldn't find my particular issue. Also a point to note, I am supposed to be heading to Moab in a little over 4 days, so time is not my friend.

My 2004 is having some trouble shifting into 4hi. When pressing the button, I can hear the actuator (will be having a friend help me check if it is moving tonight), but the button continues to blink and no 4hi. This has happened to me once or twice before, but in those situations I just tried it the next day and it worked. However, that was not the case today. I know you are supposed to engage it once a month, but I cannot remember if I did that for the past 2 months or so.

Could my actuator be bad? Or could all the parts just not be properly lubed? Any advice/input much appreciated.

 

I think 4HI needs to be engaged while moving for it to engage fully.

4LO can be engaged stationary?

@Professional Hand Model will have more info.

 

Are you rolling your wheels while engaging. Another trick is slightly tapping on the Actuator while engaging (at stop in Park please), then drive and try.

 

@Professional Hand Model Yep, rolling my wheels while engaging. I will try the tap trick!

 

It was recently suggested in another thread that you should also grease your 4x4 drive shaft or do both while you're at it. That shouldn't keep it from engaging but it can't hurt.

 

Update: Think I may have found the issue.
I'm 90% sure that is actuator vacuum line. Which I think is supposed to be in that hole? Anyone ever put one of these back in?

 

Yeah. Thats an easy one. Clean off the nipple up high and slip the hose back on. Mine did this a long time ago and I put it back with no problem.

 

Might as well check your other Actuator. Check all your engine bay vacuum hoses under the hood as well. Swirl your breathers etc.

 

I can hear movement in the transfer case actuator, but not the front actuator. Also, is the nipple on the front actuator supposed to be the same as the nipple on the transfer case actuator? (Size, location etc.) kinda seems like mine has broke off

 

I can’t remember for sure, but seems like they were both the same. Take pics of both and post them up so we can see.

 

Picture of Front Diff actuator:

 

Picture of T-case Actuator:

 

Where is the nipple?

 

Well that’s my issue. I don’t see it on the front actuator. But on the T-case actuator you can see the hose connected

 

I’m too lazy right now to crawl under my truck and confirm stuff. I’ll look on my FSM and see what I can find.

 

Sweet, thank you. Another question that might be helpful. When normally shifting into 4hi, does the front actuator make noise?

 

The front is electrically operated and not by vacuum. I’m tired, but almost certain their is another actuator with a hose in addition to the Transfer Case. Can’t help much farther than this as mine has never been a problem other than a hose slippage.

 

Yes. The 4Hi makes a noise. The 4Lo has a noise, as well. 4Lo is a deeper clunk.

 

Just to clarify some confusion, that rubber hose is nothing more than a drain line/vent. No vacuum involved. My suggestion would be to get the truck completely off the ground and see if the T-case actuator is engaging when you select 4hi with the vehicle in drive. You should be able to look under the truck and see the forward drive shaft spin when the T-case actuator is engaged. If the A.A.D. actuator is the problem, you'll get the front shaft to spin after hitting the button, but the front axle won't engage, and front wheels won't spin.

If the front shaft isn't spinning, then the culprit is the T-case actuator.

hope that helps.

 

Dope. Ended up hitting it with a hammer, and it worked haha. Thanks so much for your help @Professional Hand Model, next time you happen to be in Bozeman Montana, you know who to hit up for a beer

 

You should probably remove the case and see is the contacts are still in good shape. Lots of them get corroded and work intermittently.

 

Beware of opening these assys up as there are lots of things that will slip out of place and you’ll not know how to put them back.

 

Where does the hose drain from and where does the other end drain to?

 

Ive read about one guy taking apart his actuator, cleaning off the contacts and re-applying electrical grease to fix a similar issue. It gets pretty gnarly inside with age and lack of use.

 

Ye. I’ve probably seen that one, as well. Looks like lots can go wrong in there.