Need help with transmission

[jeepjerk]

1993 jeep grand cherokee LT 4wd, 4.0ltr 6cyl engine

Just the other day while backing the jeep out of the garage something really strange happened to my transmission.

Seems like all the shift points moved.

Park is now reverse. But locked of course and the engine dies.

Reverse is now neutral and neutral is now drive.

Can someone tell me what happened here?

I didn't try to drive the car because I thought I would damage the trany further.

Anyone have anything I can try?

[jeepjerk]

guess no one here has ever seen this problem

[fredjacksonsan]

When you say it seems like it's locked, that's bad to me. How many miles and what engine?

[jeepjerk]

Hi Fred
Seems all the shifter positions have shifted.

When the shifter is in the park position it normally locks the transmission right?

Park should be a neutral like position normally.

But now when I put the transmission into park it locks the transmission like it should in park but for some reason its in reverse and it can't move so it kills the engine.

I've checked the cable both bottom and top and it has not slipped and moves the transmission lever(arm?) its full throw.

It's got to be something internal that has broken or slipped to cause this slip in detent positions.

I guess I'm going to have to go to the local dealer and put myself in the mercy of those clowns

[fredjacksonsan]

Again, how many miles on? If it's over 200k then it might be time for a rebuild. Did the problem start suddenly or gradually?

I've read a lot about the NSS (neutral safety switch) in the Cherokee section. Apparently when it gets dirty it can send incorrect signals and cause issues like what you're experiencing. Check the Cherokee section, there are several threads where people cleaned their NSS to get back on the road.

If that's not it then I'd agree it might be time for service.

[jeepjerk]

yes it is over 200k

would the nss switch cause park to be reverse

reverse to be neutral

and neutral to be drive?

[jeepjerk]

yes the problem happened suddenly. When I backed out of the garage it was acting normally. By the time I tried put in park at the front door it killed the engine.
I couldn't figure out what happened.
I tried to start it in park, it turned over but seemed like the starter was under great load.
Then I put it into neutral and tried to start. It started and just took off. It had started in drive because it thought it was in neutral. Then I shifted around and found that reverse now acted like neutral.
Could a screwed up NSS switch cause this?
Does this transmission shift electronically?
Does anyone know exactly which transmission is in this car?

[fredjacksonsan]

Originally Posted by jeepjerk

yes it is over 200k

would the nss switch cause park to be reverse

reverse to be neutral

and neutral to be drive?

With this and your following post, it sounds like there might be multiple problems. The NSS won't cause the gears to be different, that's usually a linkage issue. But the NSS malfunctioning will allow you to start in something other than Park or Neutral.

[jeepjerk]

I just re verified everything.

You cannot start the engine anywhere but park and neutral. Like it should.

But since park is now reverse it doesn't want to turn over there.

The engine will turn over in neutral but since this is now drive or some forward gear
the car wants to move forward when you crank and will take off if it starts.

I looked under the shifter console and everything looks connected and in place.

Is there any adjustment in the cable that goes from the shifter and the transmission?
Could something have slipped here and be causing this?

Like I said before the lever where the cable attached to the transmission seems to be going it's full throw. But since I don't know how far it went before this happened I am not sure.

Is there anything I can try here before I have it towed to the dealer????

[fredjacksonsan]

I have to say that I'm out of ideas. I've never encountered something like this, unless the transmission needed a rebuild.

[jeepjerk]

Someone told me the linkage has slipped and to adjust it. The linkage is a cable and I don't see that it has slipped.
In a couple days I will have it towed to the stealership.

[jeepjerk]

I decided to drive the jeep a little today. We are on a farm so I have plenty of fields to drive around on.

I started it in neutral. It won't start in park because I think in some gear there. The parking pawl is engaged though and it can't move.

At first neutral seemed like neutral, but then after a few seconds it started to go forward in neutral.

Ok so I put it into drive. It shifted through first and second.

Then I got up the nerve to try it on the gravel road.
The transmission shifted through all the forward gears normally.
I tried down shifting using 2 and 1. All seemed normal.

But there still is no reverse in the "R" position. It almost seems like another forward gear, but not. Sometimes it will bog the engine in reverse and then lets up????

So maybe all this will give someone some more clues.

thanks

[theFREAKnasty82]

check the shifter linkage at the transmission itself. Either have someone inside the vehicle holding the brake and remove the linkage off the ballstud on the transmission and shift it yourself. You could also jack up the wheels off the ground and do the same thing, just make sure you put it in N before going in or out of R or D. It sounds like your linkage is off/out of adjustment.

[fredjacksonsan]

The more I hear, the more I'm thinking rebuild. If the problems were always the same it could be the linkage; but since things change....

[jeepjerk]

Yes I'm thinking rebuild or replace myself.

What's confusing me is that why are all the forward gears working so well?

Probably if I knew more about the inner workings of the auto trans I would be more clear.

Give me an old manual trans any day.