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Ok, so I got rid of my 24V with headaches, and apparently picked up a 12V with someone else's headaches.. So, out of the frying pan, into the fire.I've been working out some kinks on this '97. I test drove it last friday, and from what I recall, it seemed to be fine.. Unless I didn't notice it (my fault for lack of due-diligence.)At any rate, the issue (for this thread) is the transmission.Story goes: 2 owners ago, dude bought a Jasper trans, installed it, killed it, warrantied it, killed that one, warrantied it, killed it, then Jasper said "this is your last one."so he pulled the 5spd from this '97, installed the Jasper auto in it, and stuck the 5 speed into the truck that he was using to kill transmissions.However, he did a ____-poor job, and sold it to last owner, who killed the poorly/improperly incomplete install in short order. So he took it to a diesel trans guy in MD, who rebuilt the Jasper trans using triple disc TC, red clutches, kevlar bands, HD valve body, etc. (parts from HTS Diesel).Installed a PCM (to replace a non-existant one) and rewired everything, so to speak, or so the story goes.Fast forward to me.. ( I don't need any "I told you so" type stuff, because I know. Believe me, I know.. One word: Wife. )I drove it home last friday, and all seemed well, although I did notice it seemed to rev a little higher to get it moving.. Granted, I'm new to autos, as my '01 was a manual, and the '96 before that, was manual, so I'm somewhat rusty on how they perform/react. Thought maybe the TC had a little higher stall.Last night, my 7 y.o. daughter wanted to ride around the block in the new dually.. Wish granted. That's when I noticed that something wasn't quite right... No low/1st gear engagement. Neither with shifter in D, or if I manually drop it to L (1), nothing, nada.. it seems to stay in 2nd gear or so.. I will add that if in D, at a stop, let off the brake and the truck starts to creep forward.. give a little throttle and drop it into 2nd, it feels to almost 'drop' a gear, as the forward progress seems to be a more positive engagement, but still no 1st. Driving 30mph, slow prepare for a stop sign, drop lever to 2, it downshifts.. drop to 1 from like 10mph, no gear change/drop occurs.. it stays in 2nd..TC lockup and such works, and with the 4.10s, 60-65mph yeilds about 1900-2000rpm.The Coolant Temp Sensor circuit is fubar somewhere, as is the tach in the I/C. The tach does read through the scan gauge, however, so the Crank Position Sensor seems to be operational.I was told this trans has a 3/36 warranty, but getting that info is proving to be a tad on the tough side..Trans looks fresh, complete with gray paint, Jasper stickers, etc., so it was apparently rebuilt in the Jasper case.Help. I need to troubleshoot this as inexpensively as I can, for obvious reasons.

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I pulled a switch assembly from a JY truck, so the proper switch (dash-mounted) is installed. Now, that isn't to say that something is just wrong with the switch, itself..

But, did the JY switch work right??? If you wanted to be able to lock out O/D you could just put a switch to ground on the PCM.....
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But, did the JY switch work right??? If you wanted to be able to lock out O/D you could just put a switch to ground on the PCM.....

I had that, before, with the butchered harness. The OE switch works correctly but the indicator, as to whether or not it is enabled, does not. Sent from my SPH-L710 using Tapatalk 2

Is this thread ever going to die :banghead::banghead::mad::ahhh::ahhh: is this thing fixed or what!

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If you read it, you'd see that it still has issues. Sent from my SPH-L710 using Tapatalk 2

Good info here, Just bought me 01 2500 the tranny in mine works great so far, I have built a few 727s ( older mopar trannys ) the 47re externally looks similar to the 727 and iv pulled the pan and it looks about the same as the 727 so if I ever have a issue I will probably rebuild it myself, the manual valve body will eliminate all issuses with shifting but you will be having to shift into gear yourself and a manual vb will have increased line pressures and hard hitting shifts and a longer lasting tranny, I am going to check with John Cope @ Cope Racing Transmissions hes a mopar tranny builder and ask him about any mods for the 47re, and like the 727s and 904s the 47re looks like it still uses the throttle pressure for shift points, I hated the throttle kick down on older trannys so id always use a transpak or manual vb, the way they worked is the more you pull the lever or cable the higher the line psi and higher rpm and harder the shift, the less the the pull on cable or lever ( lower line psi ) the faster the shift will occur and softer, im not an expert but hope this helps

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The 47re line pressure works the same way with the tv cable. Sent from my SPH-L710 using Tapatalk 2

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So, after swapping the harness and pcm, I remembered, today, that I still had the jumper in the TCC relay spot for the TCC toggle switch.. So I pulled over, removed the jumper, and re-installed the relay. Guess what? Problems.... :cry:Trans takes off in 3rd gear. Swapped relays with horn one (I think), same issue. Pulled the relay, re-installed the jumper, trans is back to normal..I'm really starting to think I'll be needing to pull this trans this year for a rebuild or swap... This is getting old.. No, it's already gotten old..

Rick, did you by chance shut the key off then restart it with the relay in? The reason I ask is because the PCM on mine needs to be reset when it goes into limp.

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Rick, did you by chance shut the key off then restart it with the relay in? The reason I ask is because the PCM on mine needs to be reset when it goes into limp.

Yes sir, I sure did. I shut the truck off, replaced the jumper with the relay, then restarted the truck. When I put the jumper back in, I started the truck and it started off "normally"..
  • 2 weeks later...

Ever figure anything out on it?

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Only issue remaining is the OD engagement. It's really early. Maybe it's the tps I dont know. Ill try to do some more testing this long weekend. Sent from my SPH-L710 using Tapatalk 2

At what speed does your trans shift into O/D? Mine is at 47MPH with 'normal' throttle. Keep in mind that your PCM only looks at the TPS and the speed sensor on the side of the transmission to determine the proper gear. If you need a TPS NAPA has them and I am sure that other parts stores will have them too. NAPA TPS AutoZone TPS

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with the tv cable adjusted where it is, the trans shifts 1-2 @ about 1700rpm, then 2-3 again at around 1700rpm, then OD immediately after the 2-3 shift, then feels like is "slips", since the OD shift is so early. If I put the TCC relay in and remove the jumper, it seems to take off in limp mode. Bear in mind that this is the same with 2 different PCMs.

That just doesn't make a bunch of sense. Have you tried tightening the TV cable a little? I had a car that I changed the transmission in and until the TV cable was set right it would shift way early. I still don't understand the jumper issue though.......

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That just doesn't make a bunch of sense. Have you tried tightening the TV cable a little? I had a car that I changed the transmission in and until the TV cable was set right it would shift way early. I still don't understand the jumper issue though.......

Yeah I hear ya. 1-3 shifts fine, its only the OD thats the problem. Sent from my SPH-L710 using Tapatalk 2

Here is a suggestion. Try scanning the computer for codes. My '96 had a code for the transmission stored when I first got it and didn't light the check engine light. You may have a solenoid screwing up on you. Also maybe try sending Dave Goerend an email. www.goerends.com I just went to that site and found something that may be of interest. Read this for some more info on shifting: http://www.goerend.com/index.cfm?Page_name=VBA%20Purpose

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Here is a suggestion. Try scanning the computer for codes. My '96 had a code for the transmission stored when I first got it and didn't light the check engine light. You may have a solenoid screwing up on you. Also maybe try sending Dave Goerend an email. www.goerends.com I just went to that site and found something that may be of interest. Read this for some more info on shifting: http://www.goerend.com/index.cfm?Page_name=VBA%20Purpose

[h=1]What is the purpose of the VBA Goerend Transmission[/h] Valve Body Assistant (VBA) The VBA is a voltage limiter that limits the voltage returning from the transmission governor pressure sensor. The computer sends a 5 volt reference signal to the governor pressure sensor inside the trans and monitors the returning signal to determine what governor pressure is, the computer also monitors the output shaft speed sensor. After looking at the speed sensor and determining what gear the trans should be in, the computer will vary the ground circuit on the governor pressure solenoid and the governor pressure to the shift valves will go up or down as needed. The computer checks the returning voltage from the governor pressure sensor to see that the governor pressure is correct. The original valve body will only produce about 110 psi max, and the governor pressure sensor will return about 4 out of 5 volts back to the computer and the computer will read this 4 volts as prox 110 psi.

Your new valve body will produce about 175 psi so now the governor pressure sensor will return almost 5 volts back to the computer. Because the computer is programmed to only see about 110 psi it now thinks the sensor is shorted out when it sees over 4 volts returning to it.

The VBA is on the return side of the circuit and dumps any excess voltage over 4 volts to ground so the computer will not see it. This keeps the computer from going to limp mode.

Limp mode is when the computer takes all voltage away from the trans and now the trans will start out in 3rd gear only, during limp mode the trans will start in 3rd gear. If you pull the shifter to 2nd it will go to 2nd but it will not go to 1st.

If you want to get to 1st gear wile in limp mode you must stop and shift to neutral for about 5 seconds and then quickly all the way to 1st, and then upshift manually.

If I put the TCC relay in, this is exactly how my trans acts..

Maybe you need a governor pressure sensor?

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Maybe you need a governor pressure sensor?

I may try that, although I replaced it last fall with a Borg Warner HD one and a new pressure sensor.. Sent from my SPH-L710 using Tapatalk 2

Have you looked into testing the OD shift out, using a potentiometer wired into the TPS switch? Might help with the troubleshooting, having it locked at a set resistance, off a potentiometer, as opposed to letting the trans try and figure it out on its own... I can't view the link, since I'm still at work, but this might be the right thread, to show you what I'm talking about... http://www.dieseltruckresource.com/dev/installing-potentiometer-place-tps-t142641.html