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Discussion Starter #1
I posted a few days ago about a shifting issue and I now have figured out what’s going on. I have a 2.5L 3 Speed Auto that’s been doing something weird.

If I’m driving with the shifter in D and come to a place where I have to stop and back up, I move the shifter straight up into Reverse, back up and then move it back down into D and take off. But every time I do this my Jeep gets stuck in gear and will not shift up unless I pull over and put it in Park and then shift down into D.

Now if when I’m about to Reverse I put the shifter in Park first (before shifting into Reverse) this does not happen. Also if after using Reverse I put the shifter in park first (before shifting into Drive) it does not happen. So basically anytime I use reverse on my Jeep I have to start from Park, I cannot go straight from Drive into reverse and then drop down into Drive again without it getting stuck in first gear.

Am I crazy and don’t know how to use reverse on this damn thing? Is this normal or what?
 

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Does it start ok with the shifter in both Park and Neutral? If not perhaps your shifter cable has stretched and its length needs to be adjusted where it passes through its mounting bracket at the front of the transmission.
 

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Discussion Starter #3
Does it start ok with the shifter in both Park and Neutral? If not perhaps your shifter cable has stretched and its length needs to be adjusted where it passes through its mounting bracket at the front of the transmission.
I haven’t tried it in neutral but it starts pretty good in park. Would a stretched shifter cable have this issue with not up shifting after being in reverse?
 

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Discussion Starter #4
I just started it in Neutral and it seems to start up the same as in Park. I had thought maybe it was a computer issue like maybe the transmission still thinks it’s in Reverse gearing and won’t upshift when put in drive unless it’s reset in park but I’m no mechanic.
 

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I just started it in Neutral and it seems to start up the same as in Park. I had thought maybe it was a computer issue like maybe the transmission still thinks it’s in Reverse gearing and won’t upshift when put in drive unless it’s reset in park but I’m no mechanic.
It could just be the NSS (Neutral Safety Switch) which is an external switch mounted near the rear of the transmission. That could cause that issue too. Your computer has nothing to do with that transmission except for turning the Overdrive on & off as appropriate. Your transmission is not otherwise controlled by the computer.
 

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Discussion Starter #6
I just started it in Neutral and it seems to start up the same as in Park. I had thought maybe it was a computer issue like maybe the transmission still thinks it’s in Reverse gearing and won’t upshift when put in drive unless it’s reset in park but I’m no mechanic.
It could just be the NSS (Neutral Safety Switch) which is an external switch mounted near the rear of the transmission. That could cause that issue too. Your computer has nothing to do with that transmission except for turning the Overdrive on & off as appropriate. Your transmission is not otherwise controlled by the computer.
Thanks for the input Jerry! I’ll look into the shifter cable and the NSS and update the thread afterwards.
 

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Discussion Starter #7
I took it to my transmission shop here in town and they said they couldn’t get it to act up, they did say that my thermostat was stuck open and that could cause problems with the transmission not shifting correctly. So I’m gonna replace that and see what happens next, I’ll keep this thread updated for reference.
 

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Your shop is wrong, a thermostat that is stuck open causing the engine to run too cool would not affect your 30RH transmission since it is not computer controlled other than its lock-up torque converter. Its shifting is controlled purely by hydraulic means and a good transmission shop would have known that.
 

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Discussion Starter #9
Your shop is wrong, a thermostat that is stuck open causing the engine to run too cool would not affect your 30RH transmission since it is not computer controlled other than its lock-up torque converter. Its shifting is controlled purely by hydraulic means and a good transmission shop would have known that.
I just got it back from the shop and apparently there was no T stat in it at all. They said it was throwing a code P1281 and it was affecting the shifting. I’ve only had the Jeep for a couple of years and never checked it though I did notice that it ran cool. They put a T stat in it, cleared the code and sent me on my way. They checked the NSS and said it was working fine. I will be testing it out more this evening to see if I can get it to lock up in gear again but it has worked so far. I will be following up with more details as I have them. I believe you Jerry so I will be putting it through some tests tonight when I get a chance and report back.
 

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I would not go back to any transmission shop that claims a 30RH or 32RH's shifting is computer controlled or thinks a bad or missing thermostat would affect its shifting.
 

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Discussion Starter #11
I would not go back to any transmission shop that claims a 30RH or 32RH's shifting is computer controlled or thinks a bad or missing thermostat would affect its shifting.
You’re right it’s not working still. Just got back from a long test drive and it did it again. Sent them a video of it. I tried looking up tutorials online for replacing the NSS and adjusting the shifter cable but I couldn’t find anything. I have no problem attempting the repair myself especially after what happened and given your advice. Usually I can find something online to use as a guide but not this time.
 

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There's no adjustment needed after replacing the NSS switch.

How is your TV (kickdown) cable adjusted? It should be just taut/no slack but not pulling any at all until you step down on the gas pedal. It is adjusted at the throttle body where its cable passes through its mounting bracket.

Check your ATF level. Start the engine, pull the parking brake on, then shift to Neutral. The ATF must be at the full mark. Being even a little low/not at the full mark will cause shifting problems. The 30RH and 32RH can only have their ATF levels as described. Not in Park, not without the engine running.

If the ATF is low bring the level all the way up to Full. Add only ATF+4, no other type of ATF is correct. Nope, not even Mobil-1 ATF is correct.
 

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Discussion Starter #13
I drove the Jeep to get it up to temp, put it in N and checked the ATF fluid and it was in the “OK” cross pattern part of the dip stick so I added some ATF 4 to it and brought it up to full. Took it for a Drive. When I got home I shifted from D to R then back into D and it wouldn’t up shift past first again so it wasn’t the fluid level. I am planning on just buying a NSS and replacing it once I find a tutorial on how to do that. It looks like I have to drop the skid plate to get to it.
 

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Discussion Starter #14
There's no adjustment needed after replacing the NSS switch.

How is your TV (kickdown) cable adjusted? It should be just taut/no slack but not pulling any at all until you step down on the gas pedal. It is adjusted at the throttle body where its cable passes through its mounting bracket.

Check your ATF level. Start the engine, pull the parking brake on, then shift to Neutral. The ATF must be at the full mark. Being even a little low/not at the full mark will cause shifting problems. The 30RH and 32RH can only have their ATF levels as described. Not in Park, not without the engine running.

If the ATF is low bring the level all the way up to Full. Add only ATF+4, no other type of ATF is correct. Nope, not even Mobil-1 ATF is correct.
First of all Jerry I want to say thank you for your help with this and for continuing to respond to my thread and help walk me through this issue. After doing the ATF check you told me to do I decided to check the TV cable as you said. I’m no mechanic so I had to look up what the TV cable was on YouTube and how to adjust it and you were exactly right, it was the TV Cable that was loose and causing it to shift too quickly and apparently stopping the trans from upshifting after using Reverse. I pulled it out about an 1/8” so it was taught and holy crap it works! It’s shifting at about 25-2800 RPMs and now when I shift from R into D it is no longer stuck in first but is up shifting normally through all three gears! You figured out what a transmission shop couldn’t and it took me, a novice, about five minutes to fix, you are a damn genius! Thank you very much. At this point I’m not going to bother with replacing the NSS unless it acts up again but so far it’s working beautifully.
 

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Discussion Starter #16
Apparently I got it mostly fixed. Today I took it up a somewhat steep, paved canyon road, I got to the top, used Reverse and then dropped her straight into Drive to coast down. I coasted at about 25 MPH, it’s pretty steep and I could feel the RPMs picking up due to the engine braking kicking in. When I got to the bottom and went to take off it wouldn’t shift up out of first again. Had to pull over and put it in Park and then Drive again.

Now this is the thing, when I got home I popped it in and out of Reverse and Drive 5 times and it upshifted afterwards which it would NOT do before. It used to get stuck in first gear every time after using Reverse. So I know that adjusting the TV cable did something but for some reason that inclined road trip triggered the problem and I could feel it on the coast down. Talk about weird. I’m thinking maybe I need to adjust/pull out the TV cable a bit more. I don’t know. I know that the accelerator cable is a little loose there’s about 1/8” slack at the end on the throttle, see pic.

So problem is mostly gone but still happens when driving on steep terrain. I’m determined to figure this out now.
 

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