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47re Not downshifting into first

21K views 19 replies 10 participants last post by  Dynamic 
#1 ·
I know there's pages on this issue but I still have some unanswered questions. I had my tranny mildly built about a year ago. Fresh everything... I know that this issue involves the governor pressure solenoid going bad. My problem is that my transmission has all new parts, would this still be the cause? It started doing this a couple months ago but only every now and then. Now it does it every time I come to a stop. :banghead:
 
#5 ·
I know that often when a transmission is built with an upgraded valve body or shift kit the line pressures are jacked way up. This causes a computer problem as the new better higher line pressure is seen as a failure of an electronic part.

Perhaps you need one of these. Even if that is not the case at least you can read and see if the problem sounds like what they are trying to solve.
DTT VOLTAGE REGULATOR

I believe there is also a way to add a resistor inside the transmission to change the voltage to something the PCM can accept. Perhaps that was done and the resistor has gone bad?

Read this. It may be of help.
http://www.cumminsforum.com/forum/9...-47re-transmission-troubleshooting-chart.html
 
#6 ·
#1 stop driving it. had this prob and had to rebuild my trans and i was not happy.. i have dtt parts in mine shift kit and i also have the dtt voltage regulator in my truck and it works great. you have to set the regulator to a set voltage i believe its between 12.4 and 12.7... if ya get it the instructions come with it.
 
#7 ·
Well I can't just not drive it, it's my only vehicle. I have to manually shift it into first so hopefully that won't hurt it too much... Anyways I'm going to look into that voltage regulator. Where does it install? Thanks.
 
#8 ·
I recently researched this myself because I just drove home a new to me '96 dually and it was never leaving 3rd gear. Does the truck shift into OD? Does the converter lock up? If it doesn't, then you might be lacking electrical power to you trans. Obviously if the TCC locks up or it shifts into overdrive then you have power but maybe not everywhere it is needed.
 
#10 ·
i am also wondering where the voltage regulator will instill also, since i am having the same exact problems as the op mine will through a code every so often for high line pressure.
 
#11 ·
Pretty sure it gets spiced into the harness between the sensor and PCM. I'd doubt it goes inside the pan. Could probably go anywhere between the PCM and trans. It is probably a step down converter. Meaning it offsets the signal out of the pressure transducer down by some amount but still keeps it proportional to the line pressure. Making the PCM think the pressures are normal but still variable.
 
#13 ·
I put my voltage regulator on the top, back inside part of the fender where it is protected by the hood. To install it you have to cut a wire (feels bad but works good). Then a couple of soldered connections and a good wire to ground and it is done. It does include instructions and is easy to do. It hurts more thinking about doing it than doing it actually hurts.
 
#15 ·
Well I installed the regulator. Worked fine for a bit and now it occasionally has 2nd and 3rd gear starts. I've been changing the voltage to see if it helps but it doesn't. No idea anymore.
 
#17 ·
Change the gov pressure sensor and the gov solenoid. They'll run you about $140 for the pair and cure your 2nd gear starts. I work at a transmission shop and we have at least 1 dodge in a week with this problem. Those 2 sensors fix it every time.

Typos courtesy of autoguide
 
#18 ·
Change the gov pressure sensor and the gov solenoid. They'll run you about $140 for the pair and cure your 2nd gear starts. I work at a transmission shop and we have at least 1 dodge in a week with this problem. Those 2 sensors fix it every time.
He beat me to the answer. The other possibility is corrosion in your wiring. Sometimes corrosion in a connector or a soldered joint can cause electrical issues.

Although the voltage regulator adjusts your voltage it does not make up for a bad electrical part.
 
#20 · (Edited)
What valve body work was done during the build? You shouldn't need that regulator if the proper VB mods have been done. It should be exhausting excess governor pressure, not lying to the PCM about it...

It sounds like you could possibly have a bad transducer. Excessively high governor pressure often takes them out. I would change both the transducer and the governor pressure solenoid, as has been recommended.

I use the Borg Warner HD solenoid exclusively. I have yet to see, in any case, that the GM conversion works any better than the HD Borg...and it's a ton cheaper! You should be able to get both parts for under $100. They're easy to change, too...
 
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