Did you check to see if one of the shifter rods didn't come loose and and the pin fall out. If I remember each shift rail has 3 positions and maybe the one shift rail came loose , my twin stick has a front wheel drive only how else would you be able to move the front end over unless it had that option?

 

If one of these pins no1 fell out or rusted away you could get that.

 

Um, no - you could not. There is no contingency for FWD high in the D300 as the OP stated. This means that no failure in the external shifting mechanism would cause FWD high.

This means the case will need to come out. Hopefully its just an issue with one of the shifting forks, but be prepared for a bench rebuild (or find an operational case for $100 and swap it in)

 

Correct me if I'm wrong, but isn't that one of the reasons for installing the twin sticks? The ability to shift the front into high and the rear in neutral, which would essentially be front wheel drive high.

 

I always thought the ability to have FWD Low was the reason. And the ability to pop the front out of Low into Neutral if you have a front locker and want to make a tight turn on the trail.

 

I always thought the ability to have FWD Low was the reason. And the ability to pop the front out of Low into Neutral if you have a front locker and want to make a tight turn on the trail.

There's numerous reasons to opt for twin sticks, as your's are good too. I'm just confused because earlier posts were claiming that FWD high wasn't a choice, but it would be with a twin stick. I could see the benefit of this if you hit a really bad patch of icy pavement going uphill. You could switch into FWD high and pull yourself up it. But as you mentioned, I'd see your scenarios happening more often.

Anyway, OP, I think if your linkage is bad, like BagusJeep mentioned, I could see this causing your issue. Keep us updated!

 

Open it up and look inside but verify the pins are there on your way. The grinding makes me think internal problem..... Unless a linkage pin failed like bagus said and the t-case was shifting at a bad time causing the grinding.

 

Open it up and look inside but verify the pins are there on your way. The grinding makes me think internal problem..... Unless a linkage pin failed like bagus said and the t-case was shifting at a bad time causing the grinding.

I agree. The grinding is definitely a concern. Verify the linkage is good, and if it is, then you're most likely looking at some bench work.

 

Anything's possible in an old CJ, but the D300 is very strong so fingers crossed it is something simple.

 

RamblingCJ and Pacfanweb - The reason for a twin stick is two fold. #1 is (as Pacfanweb stated) the ability to easily disengage the front axle if you do not have a selectable locker and need a tight turn. The other reason is in order to do front digs which can get you out of a jam if you are in a bad situation (or sometimes just save you from having to make a 12 point turn).

Both of these situations are for use on the trials, in 4WD LOW situations. The detents on the shift rails of the dana 300 will not allow the case to shift into 2WD high - trust me, I have tried. Twin stick or single stick, you just cannot do it if everything is in working order. Even in the situation on having twin stick with both sticks in 4wd high and you attempt to pull the rear axle stick into neutral the front axle stick will come with it (basically bringing the t-case into neutral).

In conclusion - there is 100% chance that there is something going on inside the TC that should not be. It *may* be possible to get RWD high back by playing with the shift rails but if you were to successfully get RWD high back I would not attempt to cycle into 4WD high (or any other t-case configuration) else you will be right back where you started.

 

Thanks guys. I am out of town with the Jeep (FL for 7 weeks using it as my daily driver) so 95% of my tools are in MI and the RV park would scream if I started tearing down my TC here even if I had the tools. Bottom line, I took it to a tranny shop, they took it apart and yes something was broken. I will find out more when I pick it up in few days. I am guessing it was a delayed result of either:

1. My 0-60 test when I blew the driveshaft U-joint straps at 53 MPH at 6 grand on the tach
2. The contamination of the TC oil with ATF due to a bad input shaft seal.
3. Low TC oil level due to some loose bolts on the bottom inspection plate from an earlier tranny rebuild and the shop (in MI) resealing the TC.
4. Hey, it is 27 years old and had never been taken apart.

 

RamblingCJ and Pacfanweb - The reason for a twin stick is two fold. #1 is (as Pacfanweb stated) the ability to easily disengage the front axle if you do not have a selectable locker and need a tight turn. The other reason is in order to do front digs which can get you out of a jam if you are in a bad situation (or sometimes just save you from having to make a 12 point turn).

Both of these situations are for use on the trials, in 4WD LOW situations. The detents on the shift rails of the dana 300 will not allow the case to shift into 2WD high - trust me, I have tried. Twin stick or single stick, you just cannot do it if everything is in working order. Even in the situation on having twin stick with both sticks in 4wd high and you attempt to pull the rear axle stick into neutral the front axle stick will come with it (basically bringing the t-case into neutral).

In conclusion - there is 100% chance that there is something going on inside the TC that should not be. It *may* be possible to get RWD high back by playing with the shift rails but if you were to successfully get RWD high back I would not attempt to cycle into 4WD high (or any other t-case configuration) else you will be right back where you started.

Thanks for clarifying that!

 

Thanks guys. I am out of town with the Jeep (FL for 7 weeks using it as my daily driver) so 95% of my tools are in MI and the RV park would scream if I started tearing down my TC here even if I had the tools. Bottom line, I took it to a tranny shop, they took it apart and yes something was broken. I will find out more when I pick it up in few days. I am guessing it was a delayed result of either:

1. My 0-60 test when I blew the driveshaft U-joint straps at 53 MPH at 6 grand on the tach
2. The contamination of the TC oil with ATF due to a bad input shaft seal.
3. Low TC oil level due to some loose bolts on the bottom inspection plate from an earlier tranny rebuild and the shop (in MI) resealing the TC.
4. Hey, it is 27 years old and had never been taken apart.

Ouch! I've thrown one, but not at that speed. I bet that was pretty loud! I hope it didn't mess the bottom of the tub up too much!

Hope they get ya fixed up and road worthy quickly so you can enjoy it with the weather down there!

 

The blown DS beat up the fiberglass tub pretty bad along with my brand new SS Magnaflow muffler. Here is my saga: http://www.jeepforum.com/forum/f8/stupid-me-1432411/

Just picked it up from the tranny shop. A detent screw had worked itself loose and jammed up the shift mechanism. Good news was no big parts bill, bad news was $1100 in labor.

 

just picked it up from the tranny shop. A detent screw had worked itself loose and jammed up the shift mechanism. Good news was no big parts bill, bad news was $1100 in labor.

ouch