Got stuck in 4 L0, how can I prevent it?

[Rob_B]

Alright, I couldn't sleep last night so I had teh "brilliant" idea of going through some mud. It wasn't anything bad, but I put it in 4 Lo because I hadn't used it in a while, it engaged fine. There was hardly any mud and when I went to leave I put it in Neutral and in 4 Hi and it wouldn't shift. Restarted, tried a bunch of time's to no avail. Luckily my house was halfa mile away, so I limped it home, and taped the t-case motor w/ a hammer and I got it to switch. Also by the time I got home my OD off light was flashing again, but that hasn't happened sense I got it out of 4 Lo.

Basically I wanna know if there's anything that caused this, or is there anything I can do to prevent it from happening again? The only thing I can think of is change the t-case fluid, and maybe grease the where the motor engages.

Also I haven't changed any fluids other than oil and tranny, so if I change the t-case this weekend, should I do the differential's too, and how hard will it be? I'm fairy mechanically inclined, I just have never changed t-case fluid b4.

 

[Lifted95X]

Put it in 4HI, then reverse...and drive back slowly for about 20-30 feet. That usually does it for me.

 

[Rob_B]

I tried it again this afternoon, this time it wouldn't go into 4 Lo. I tried rocking it back and forth some, backing up a bit, restarting it, even put it in neutral and let it coast for a while. Something's messed up. The only thing I can think of is to check and clean all the t-case wiring.

My owner's manual say's something about lubricating the t-case pivot bolt and connecting pins. I'll try to check that out this weekend, do you guy's have any other idea's? Thanks

 

[Xplodor]

My electronic shift motor went bad 6 months after I bought my truck new. Check into that.

 

[mikeh]

I had that problem once. I tried everything. Stopped the truck. Backed it up. Turned it off and on. It finally popped back out and ran fine. My solution was to never switch it to 4low again

I just changed the Xfer case fluid this weekend after 82K for the first time. The fluid looked brand new that came out of it. It's really easy. You just need some type of pump to put it back in. Regular Mercon transmission fluid is what is recommended not the Merc V stuff that is in the transmission. It only takes 1.3 quarts but I spilled so much I used a full 2 quarts.

mikeh

 

[Rob_B]

Thanx, I'll just avoid goin anywhere where I'll need 4 Lo . This has brought up another question, since my 4 Hi works fine, does this mean the shift motor does nothing when I switch from 4 auto to 4 Hi?

I also think my motor was replaced once already, so if it's bad already I'm not going to fix it as long as 4 Hi works and it doesn't trip the computer.

 

[oso_polar]

Our t-case should be the same, so the shift motor only have two positions, 4Hi---N-------4Lo, well three, but it never stop at Neutral, if you put in Neutral the truck will not go anywhere...

So... maybe you will have to clean your shift motor, is not that hard, I did mine about two months ago, but that was not my problem... If 4Hi is engagind, then the electromagnetic clucht should be working, because the shift motor doesn't have to move... but if the 4Lo isn't engaging, then the shift motor is not working...

If you want to check this, just crawl under your truck and get someone to shift the 4x4 swicht, if you hear something, then the problem could be the t-case...

Dead Link Removed You will find some cool info about cleaning the shift motor, not from a new gen, but I think the motor is the same, I found it just after I finish mine... Please don't do this if you don't have the tools or some minor skills on mechanicals...

 

[TPLYNCH]

Try resetting the computer by disconnecting the battery for ~30 Minutes before you start tearing the shift motor apart. Sometimes the motor loses track of where it is, and resetting the computer will fix. Also works when it is stuck in 4-lo. Would have tried that before using the BFH. If computer reset doesn't work, take out the shift motor. I have a feeling you may have broken one of the magnets inside when you banged it. Someone else on the board had that happen to them......

 

[Rob_B]

Thanx for the info. I'll look into cleaning the shift motor when I change the transfer case fluid.

Mikeh, what kind of pump did u use to get the fluid in? I can't think of any pump small enough that'd work. I'm studying to be an engineer, maybe I'll jus hafta get creatve.

 

[mikeh]

Rob,

I used one of those suction pump things that they sell at Autozone (or any place) for $10 bucks. It looks a little like a grease gun. You just suck it up into the gun and then stick it in the diff and squirt it back out.

Turkey baster takes about 2 hours . But don't tell the wife.

mikeh

 

[Rob_B]

To clarify, I didn't beat it w/ a BFH, I jus gave it a couple small taps to loosen it up w/ vibrations through the housing. I doubt I broke anything that wasn't already busted. I remember reading a post a while back about tapping the motor to free it up. It was after midnight when it happened, and I my only goal was to get it out of 4 Lo b4 I had to suffer the consequences in the morning.

I'm not going to replace the shift motor if it's bad, since the 4 Hi will still work. I'm pretty sure it was replaced the week I bought it (they replaced the motor, but that wasn't the problem, they might have put the old one back in , it did look pretty shiny when I was under there "adjusting" it though).

 

[TPLYNCH]

You're right. That is one of the fixes. If it doesn't work after resetting the computer, then try cleaning the contacts on the shift motor. When you're doing that, you should be able to see if something is in fact broken. Heres a link to instructions for cleaning the motor. Dead Link Removed

 

[socky3850]

I agree with TPLYNCH. Reset the computer. This same thing happended to me the last time that I was offroad. I was stuck in 4Low. I disconected my battery cable for a while. When I reconnected the battery, I started the truck and moved the selector switch and it came out of 4Low. This has happended to me twice in 92K miles and it was usually when I had spun my wheels for some reason.

 

[Rob_B]

Thanx, I'll try resetting my computer later. I'll let u know if that fixed it or not.

 

[Rob_B]

ok, I've been kinda busy lately w/ finals and stuff, so I haven't been able to get into my shift motor yet. I played around w/ it, and when I go through the process of putting it in 4 lo, the light came on but when I backed it up and drove it around the gearing seemed to be the same when I held it in 1st gear, so I don't think it's engaged in 4 lo when the light is on. I had tried it a couple time's b4 that and resetting the computer to get it out of 4 lo, which did take the light off. So could have resetting the computer misaligned the shifter so it isn't lined up where the computer thinks it is, causing my problems?

I do have mechanical ability, and plenty of toy's (a.k.a. tools) but I'm not sure if I want to tear the motor out yet. I jus kinda want some reassurance that my t-case will be fine IF the motor is out of whack, but in 4 auto/hi. If there's any chance that the motor could get bumped or work it's way towards 4 lo I'll tear it apart and fix it, or try to. Not having 4 lo will probably keep me from wheeling my Ex anymore cause all wheeling it does is breaks stuff.