Transfer case slips out of gear..

[Jason Mills]

I appreciate your suggestions Frank. I am appreciating C.D. and Charles suggestions as well, as I was under the immediate belief that I was about to learn how to rebuild a transfer case, just three short days ago. It is amazing and wonderful how input from people through a computer screen can change the path that I have been thinking and open me up to new options. and help me to consider all of what may be actually a fairly simple repair, once the diagnosis has been nailed down.

Just now as I was reading your post, I had the realization that there is another transfer case in my stockpile. Why not go compare the operation of the shift levers on that, as see if they are any different?

In regards to your suggestion about driving the truck with out the shift levers attached, I will in fact try it. Yesterday after adjusting the shift levers and finding no real change, (as I can see the lever start to creep backwards with in 20 feet or less of starting to climb an incline) I allowed the truck to roll back down the hill and this time kept my hand on the lever.. it still wanted to push out of gear.. so I made the assumption that it is in fact the detent spring.

furthermore I am under the personal assumption that the detent springs cannot be accessed with out dropping the transfer case. If I am wrong in that belief, some one is invited to correct me.

Tomorrow evening I will dig out the original transfer case and observe the sounds and effort it takes to move the shift levers.. still it has not been in use since the truck was on the road which according to the last inspection sticker was 1979... It has quite a bit of back lash between the gears so I assumed the presently installed one was in better shape.

I will report my observations.

[Charles Talbert]

The plugs securing the detent balls and springs can be easily accessed with the case in place. Try this fix first as all can be replaced in only a few minutes.

One other factor with this is possible wear on the "V" groove edges that the balls engage in the shaft. They will get worn in the path where the balls travel as the shaft moves back and forth, eventually wear will become severe enough to allow the balls easy entry and release from the detent groove, thus slipping out of gear.

Another issue can be extreme wear on the splines of the input shaft and the sliding hi-lo speed gear that slides on it. When wear becomes excessive here, the sliding gear is allowed to wobble around on the shaft instead of being held in a true alignment. As it moves around, it will eventually force the gearing out of engagement. If this is happening, the spring pressure on the ball is not sufficient to hold the shifter shaft into engagement. To repair this problem, the e-brake unit must be pulled from the case and can be done without pulling the case from the frame. If I was going that far though, I would go ahead and pull the case for a complete teardown, cleaning, inspection, and a total rebuild. Most likely if things are worn to this extent, other issues are lurking also.

[Cheyenne Dave]

My bad. I was wrong in my first description. It has been 6 or more years since I had paid any attention to which lever does what (it has been a long time since the truck was together enough to not be called a pile of parts).

so to start over, when driving the truck up a hill or any type or incline the forward-most transfer case shift lever pushes backwards until the transfer case slips out of gear.. adjusting the shift levers does make the detents more noticeable, but it does not seem to help the shifter rail to stay in gear.

If the forward t-case lever (hi-lo selector) is slipping back PAST the rear lever (2wd-4wd selector), you have the additional problem of severely worn lever bushings and likely wear in the pivot shaft they ride on. These levers should not be able to by-pass one another.

I suspect this could be aggravating the problem, as well as your ears!

C.D.

[Jason Mills]

Months later

I have ended up pulling the transfer case out of the truck. After a fair amount of effort, and not being able to remove the screw/plug that holds the detent springs in place, I decided to take it off the transfer case off the truck and..... There was a small pebble stuck in the grove around one of the detent spring holding screws.. so the socket was not able to do it's job.

While it is out, I have made the decision to replace the seals and gaskets, and give it a cleaning. As the two rear output shafts were leaking. amazing the amount of muddy looking oil that is inside the case.. now to decide if it needs new bearings due to the lack of oil changes over the years.

[Gordon Maney]

How about taking some photos and writing something for us for the magazine? It is a great topic.

[Jason Mills]

How about taking some photos and writing something for us for the magazine? It is a great topic.

I am almost curious as to how that might turn out.. have you got any guidance to help narrow the topic down a little bit, at least to get me past the first sentence(s)?

[Gordon Maney]

Yes, let me post on that later today. I am processing mail right now for the issue that mails Monday.

Thanks for asking!

[Charles Talbert]

I have ended up pulling the transfer case out of the truck. After a fair amount of effort, and not being able to remove the screw/plug that holds the detent springs in place, I decided to take it off the transfer case off the truck and..... There was a small pebble stuck in the grove around one of the detent spring holding screws.. so the socket was not able to do it's job.

While it is out, I have made the decision to replace the seals and gaskets, and give it a cleaning. As the two rear output shafts were leaking. amazing the amount of muddy looking oil that is inside the case.. now to decide if it needs new bearings due to the lack of oil changes over the years.

If the oil is discolored or milky/muddy looking. Take some good advice, tear it down completely, clean everything thoroughly, check every piece thoroughly, if it's out of spec, replace it. Muddy looking oil is a very good indicator that water is mixed with the oil. Most likely you will have rust pitting on gear teeth, seal wear surfaces, and bearings. We see worse damage in t/cases from just what you have described than any other single factor. Not going through it now while it's out would not be a wise decision.

[Gordon Maney]

Thoughts regarding a beginning.

Do you have a digital camera? Try a few photos in your shop or garage. It could be a photo of your bench vise or the wheel on the truck. Just try a few and see how you do. Send them to me for comment, if you like. We want at least a few good photos.

Have your camera set to produce the highest resolution [largest size] images possible. Once you get good at taking a picture of your bench vise, you are ready to go on to the transfer case and parts.



Don't worry about how to start or how to finish what you write, or how to say it. Just tell me what you are doing, pretend you are just talking. Get the ideas down. Don't labor over a beginning for now. Just write what you are doing. In a way we know the beginning. You bought a truck.

If I get an incomplete sentence I can edit that. If I get a paragraph that need to be rearranged, I can edit that.



Do what you know you can do, which is simply tell me about it, what you did, what was difficult, interesting, challenging, and how you learned.


Talk about what you did and why.

Just talk to me....

[Jason Mills]

If the oil is discolored or milky/muddy looking. Take some good advice, tear it down completely, clean everything thoroughly, check every piece thoroughly, if it's out of spec, replace it. Muddy looking oil is a very good indicator that water is mixed with the oil. Most likely you will have rust pitting on gear teeth, seal wear surfaces, and bearings. We see worse damage in t/cases from just what you have described than any other single factor. Not going through it now while it's out would not be a wise decision.

I am in agreement, and pretty much came to that decision all ready. It is just about all apart, and I will start cleaning this weekend. In fact the inside does not look as bad as I expected, some of the bearings/races look worn and I am not sure of, at which point some wear becomes too much wear. Still there is no rust that I have seen so far.. which is a relief.

[Charles Talbert]

I am in agreement, and pretty much came to that decision all ready. It is just about all apart, and I will start cleaning this weekend. In fact the inside does not look as bad as I expected, some of the bearings/races look worn and I am not sure of, at which point some wear becomes too much wear. Still there is no rust that I have seen so far.. which is a relief.

No rust is a good thing. If bearings are worn to the point that you can see it upon visual inspection, they need to be replaced. Transfer cases require very specific set up in relation to bearing preload specs, etc. If you don't have the correct shim packs and instructions, obtain all this before you start. It would be a shame to have a catastrophic failure due to an improper set up. Another good point, they run great on Royal Purple straight 50 weight engine oil as the lube. These cases tend to run on the warm side, the Royal Purple will give you noticably cooler running temps, and it offers far greater protection on cold starts.

[Jason Mills]

No rust is a good thing. If bearings are worn to the point that you can see it upon visual inspection, they need to be replaced. Transfer cases require very specific set up in relation to bearing preload specs, etc. If you don't have the correct shim packs and instructions, obtain all this before you start. It would be a shame to have a catastrophic failure due to an improper set up. Another good point, they run great on Royal Purple straight 50 weight engine oil as the lube. These cases tend to run on the warm side, the Royal Purple will give you noticably cooler running temps, and it offers far greater protection on cold starts.

In that case I need to go on looking for shim packs, and bearings.. and the occasional pointer from those who know, as I will be in the deep end of the learning pool. Let the adventure begin!

[Jason Mills]

These cases tend to run on the warm side, the Royal Purple will give you noticably cooler running temps, and it offers far greater protection on cold starts.

Charles,

Do rebuilt transfer cases require a "break in" and flush of gear oil before switching to Royal Purple? (or not, because the gears are all ready having a wear pattern ?)

[Charles Talbert]

Charles,

Do rebuilt transfer cases require a "break in" and flush of gear oil before switching to Royal Purple? (or not, because the gears are all ready having a wear pattern ?)

If you were replacing everything in the case with new, a break-in procedure would be advisable. Wear patterns are already established, they will be changed somewhat with the new bearing set-ups and again if you have to replace any gears. This is typical, just install the 50 weight Royal Purple, drive moderately without any heavy loading on several 10 - 20 mile runs letting the box cool down between runs. After a couple of hundred miles you should be good to go. Installing a magnetic drain plug will capture small particles that are floating around.

[Jason Mills]

Installing a magnetic drain plug will capture small particles that are floating around.

I had no idea such a thing exists, although now that you say it, it makes good sense. Anyway, the break in procedure is a little ways off..