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Okay, so I was drove about 35miles this evening and when I was parking at my moms house, my truck shifted fine and firm into reverse and then it felt soft when I put it back in drive. I parked, let the truck sit for about 4hours, and went for a little drive to grab some food. When I got in, it shifted fine and felt firm. I made it about 5miles, and leaving a stop sign, the truck felt like it was still in 3rd, like it had gone into limp mode, so I got up to speed, and it kicked into O/D just fine, and down shifted out, when I used the O/D off switch. Coming to the next sign I tried manual downshifting my trans, 2nd gear no shift at around 5mph it still hadn't shifted into first so I tried to do it manually and the tires locked up. I put the truck in neutral and shifted it into drive and the shift felt soft again. It still felt firm going into Reverse though. I pulled it all the way back to 1st and nothing, it didn't feel like it engaged at all. I took my foot off the brake, let it roll forward and it locked up and held itself as if it were in park.

I turned the truck off and back on, and it worked fine, only to repeat the pattern 2 miles down the road. If I shut it off, it goes back to normal for a while, even if I take it all the way up into third, it will still shift back out, then it just decides it doesn't want to. As a result my trans temp is now getting quite hot around town because its doing this.

Anybody have any ideas? Sticking valve in the valvebody? Fluid level is fine, the fluid and filter are brand new as of 2 days ago, and have 150miles on them. I'll be calling DTT first thing on monday to see what we can figure out. I'm getting kind of tired of this though.
Sean
 

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Discussion Starter #2
I had forgotten to check codes, but just ran out and looked and I'm pulling a P1763 Gov. pressure sensor voltage too high.
So does that mean that My gov. pressure is too high and telling my PCM to go into limp mode, or is the voltage running to the sensor too high?
Sean
 

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I was pulling a P1763 on my 98.5. It was the governer pressure being set too high. So I just took off some governer pressure and it fixed the problem. You need like 1 PSI of gov pressure for every MPH.

I'm guessing you have the same problem. Your sensors are probably fine. That's been the case on all the trucks I've worked on that have had this problem. It seems like every shift kit I put in runs into that problem.

That's why I've been on a mission trying to figure out how to get the computer to think it's not getting as much gov. pressure.
 

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This file is the closest I've gotten. Their might be a transducer you can buy to correct this problem too. I would almost recommend trying to fix it electronicly so you get that added pressure. I've tried farting around with a variable resistors on varies wires coming out of the tranny with no luck. If you figure it out how to fix it losing your pressure. Let me be the first to know.

Just out of curiosity put a guage on your governer port and tell me what it reads.
 

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Discussion Starter #5
Phily 911 said:
Just out of curiosity put a guage on your governer port and tell me what it reads.
I tried putting a gauge on it earlier, after switching the electronics over, but I couldn't get it to read. It was a brand new gauge too. Any tips on bleeding them? I'm assuming that that is what my problem was.

Also, how do I adjust my gov. pressure? Thanks.
Sean
 

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to do the gov pressure you have to put a resistor inline to make it read differently. Or you can actually reduce the line pressure on the side of the valve body if it is over where it should be.
 

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sstockton said:
I tried putting a gauge on it earlier, after switching the electronics over, but I couldn't get it to read. It was a brand new gauge too. Any tips on bleeding them? I'm assuming that that is what my problem was.

Also, how do I adjust my gov. pressure? Thanks.
Sean
On the drivers side of your v/b there is a hex screw, you'll need a allen wrench cut down to fit in there. Shouldn't need bleed. I'll scan you a pick of a transmission that points it out where you need to tap into.

StrokeThisGoat said:
to do the gov pressure you have to put a resistor inline to make it read differently.
It wasn't that easy last time I tried, which I'm sure Sean is about to find out.
 

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Discussion Starter #8
When I talked to the guys at DTT they told me the port on the rear of the trans on the passenger side facing out sideways. There are two back there, and its the higher one. My gauge wouldn't even register, so I figured that there was air in the line getting compressed and not allowing it to read. I'll try again though.

Is it possible that it is too low and that is my problem? Hence it not reading. but you'd think it would come up at some point even if it was low. Maybe I got a bad gauge. I'll give it a try again and see where that gets me.
Sean
 

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Discussion Starter #10
Yup, thats the one I'm using, but I'm not getting any reading. So I don't know whats up. Maybe my gauge is broken or something, but I can't get it to give me a reading.
Any suggestions?
Sean
 

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Not even anything at 55MPH? If not your guage is broke. I'm not sure the truck is going anywhere without governer pressure reaching that port. You are going to want to figure out why your guage isn't reading there. I don't know if they do something different on the high performance cases that would some how cause that test port not to read. But I doubt it. That's pretty much the only port I know what it should be reading. It's also the most critical port as well. Any other port would be used for fine tuning which I don't know how to do.
 

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Discussion Starter #12
I'll try again when I get home. I had to install new electronics in it, one of them being the gov. pressure sensor, to get everything to work right. When I did that the trans wasn't shifting out of 1st. Thats when I got the gauge and tested and nothing. I pulled the pan and that sensor had popped out, because I didn't have the right bracket. I got the new bracket from dodge, installed it, put the gauge back on that port and the truck drove fine, but still no reading, and I took it all the way up. Thats what makes me think that there is a gauge problem. So I'll check again and I'm having my buddy bring his over so we can test with it.

On another note, I took the truck out this morning, and the same thing happened almost right away. However, I found that If I come to a stop, I can put the truck in Neutral, then manually downshift to 1st and manually run up through the gears and get them all. So I'm not affraid to make the 35mile trip back home, because I have a way to get all my gears, so I'm not leaving stop signs in 3rd.

Then I ran into the store really quick, came back out, and for the last 15miles, its been down shifting fine on its own. The fact that I did replace that sensor and that it seems to be an intermittent problem leads me to believe it may be electronic not the pressure itself. However I'll still through a gauge on there and see if I can't get a reading.
Sean
 

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sstockton said:
On another note, I took the truck out this morning, and the same thing happened almost right away. However, I found that If I come to a stop, I can put the truck in Neutral, then manually downshift to 1st and manually run up through the gears and get them all. So I'm not affraid to make the 35mile trip back home, because I have a way to get all my gears, so I'm not leaving stop signs in 3rd.
Interesting, I wish I would have tried that.

sstockton said:
Then I ran into the store really quick, came back out, and for the last 15miles, its been down shifting fine on its own.
Mine would do that too.
 
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