So my transmission 47RE is now locked in 1st as of yesterday. I cannot manually shift it from 1st to 2nd, reverse and 1st is fine. ABS on.

Plot:
Trans rebuild by a reputable company 35k ago and serviced by my transmission mechanic just 7k ago (when I bought it) where we went Fully Synthetic Mobil ATF......Lets not get into that one please. He went through it with a fine tooth comb and everything was in good shape. Bands adjusted, filter, and purged. Now it's always been hard shifting from 1st to 2nd but everything was fine after that, spring is backed all the way off and the only way to go further is to pull the valve body and that will remove the shift kit, not sure what kit was installed.

So, it's been holding 1st gear slightly and I have always just let off the throttle a little during the shift so it would engage so hard and that has worked, however the last week it has been holding 1st and not wanting to shift, I pull my foot completely off at 3k rpm and it would finally shift.

Now I talked to master tech and he gave me some options, and here they are.

Adjusted the TV cable, slightly better shifting after as it was too taught.
Adjusted the front band 1/4 turn loose, nothing
Adjusted the front band 1/4 turn tight, nothing
Fluid perfect level and clean
TPS is new and operation fine

So here I am now, I am completely locked out into 1st and the ABS light and brake light is on, no speedo, no CEL light. Now I have had 2 instances in the last 4 months that the ABS/Brake light has illuminated a pull of the fuse and reset the module and it goes out, no other speedo issues. Now my question is what do you think it is?

Master tech said if it won’t up shift manual it is a valve body, problem is they are not easy to come buy where I live. However if it did up shift then it is a governor solenoid, however that isn't the issue in this case, just figured I would put it up there.

In my opinion, I think the issue is the transmission speed sensor as it gives reading to operate the governor and also works with the ABS system, however there is no speedo after 20mph or before. The rear wheel speed sensor is OEM, but I have literally busted one in half windings and all and that only illuminated the light and nothing with the trans.

What do you say??????

 

You have a failed speed sensor. (thus, the abs/brake lites, and no speedo) need to fix that first. if you do NOT have 4 wheel ABS, highest likelihood is the sensor on top of the rear differential, or, the connector for that sensor. Check/clean the connector first, if that doesn't help, replace the sensor. Once you have those lights off, and the speedo working, see if the trans doesn't wanna shift now.

If it STILL doesn't wanna shift...... Disconnect the electrical connector on the drivers side, shortly behind the shift linkage. (should be like an 8 pin connector) Take the truck for a drive. Bear in mind, you will not have ANY automatic function AT ALL. You will have to shift each gear manually. (and o/d will never engage.....) If the trans actually shifts this way, replace governor pressure sensor and solenoid.

 

I understand the failed speed sensor can do this, and no 4 wheel it is RAWL braking. But again that sensor does nothing for the transmission, whereas the transmission speed sensor does and has ABS interface. http://www.cumminsforum.com/forum/98...out-first.html

Will try the trans unplug, but if I am right and the trans speed sensor is out, would it still shift manually because the goveror is unplugged at that point.


Regardless, both sensors together are only like $40 bucks together, just want to replace the right one.

 

I woud suggest resetting PCM also. Pulling a fuse to clear a light may not clear the stored code in pcm.

 

You miss understood what I did. I rebooted the ABS module, I wasn't trying to reset the PCM because I didn't have a stored code in the first place. Rebooting the module is a separate system then the PCM.

The only code that would be able to be read is the ABS system that would have a code stored. You need a OBD-II reader to do that which I don't have.

----------------------------------------------------------------------------
Update!

Thanks!

Got home and unplugged the the trans harness, although I haven't got parts yet I just wanted to see. I started the truck and put the trans in D out of habit. Pulled out onto the road and I was in second so I tried to manually shift to 1st and it wouldn't down shift. So I stopped and put it in park, then took it straight down into 1st and it grabbed. Took off shifted to 2nd and she went right in, then into D and she went into 3rd no problems, I then came back to a stop and it down shifted just fine all the way into 1st.

So now I think we can nail it down to an electronic issue. Sense the ABS light is on I am going to replace the transmission output sensor first, if anything it's most likely not reading right it will help with shifting and ABS. Next to rear diff speed sensor, then finalize with Governor/solenoids, band adjustment, filter, and reuse the fluid if good. Going to stop off after work at the auto parts store on my way home tomorrow and will update.

Anything else?

 

I'd replace the speed sensor on the tranny/tc first.

 

I thought in 99 they didn't have the sensor on the trans, and just used the one in the rear diff? No? What year did that change? (and I will make note of it.....)

 

I have the speed sensor on the trans on my 99.

 

Some have it, some don't. It's ridiculous actually. My 98 did not have one. Only had the RWAL sensor on the rear end.

 

Oh it has the sensor on the 47RE, it's on the drivers side overdrive assembly (for those that don't know it is the tail section on the transmission before the T-case) lower section. I know the Durango 42-44RE has a transmission output sensor as well as the 46RE, and the 45RFE which has both an input and output sensor. Now I know of some differences between them and us, but I really would assume there is some miss information over here in the Ram section as those transmissions went from 1998-2003 for sure.

The 46RE is again in the overdrive assembly drivers side, 44RE and 42RE all say they have it there as well in the 2001 Ram service manual. From what I have witnessed, I too have seen them. Now I don't mean to call anyone out on the Transmission Speed Sensor on these models, but I am fairly positive all have them, they are just not where you would think they are. Every break down I have come across have even stood by that claim! I can take a picture of it for the record if needed.


Anyway back to play!

I went to reconnect the harness and noticed it had ATF on the female end, puzzled I decided this could be a problem, but not the problem. I used compressed air to blow out the female end on the trans and then I blew out the male plug as good as I could and reconnected, as thought nothing happened but I thought I would throw it out there.

I then tested the output sensor, nothing! I tested for A/C and nothing. I tested for D/C nothing, I tested for resistance nothing, I then tested for continuity and guess what, nothing. Can't wait for tomorrow, however I have other plans and will be 100 miles from home, but damn if I'm going to come home early armed with a new sensor.