Archived 47re Transmission Problem

[MattAdams]

Hey all ,new to TDR ,been reading up on truck problems for awhile. Was reading post on 47rh problem and saw my exact same problem that my truck has! I have a 99, 2500 ,automatic 47RE with only 49,000 miles on it and never had any trans problems at all. Truck sat all night then in morn went and moved it maybe 50 ft to next door neighbors driveway backed it up driveway and put in park and let it sit till around noon then went to leave and truck won't shift!! Takes off like normal but no upshift from 1st or 2nd not sure which one it is in. when I put the gearshift into manual (1,2), and I drop it from 2nd to 1st it acts like it downshifts (A bump), but when I upshift from 1st to 2nd manually it doesnt seem to change. Can only get about 25mph out of it at around 2300rpm. Will speed up with more rpm but didn't want to push it. Ran it up only once to 2800 or so to see if it would shift but no such luck. So far I have tried scanning for codes(at Autozone) but no light is on in dash. Took it in to dealer and hoped they could find problem with there fancy scanner but no such luck, they said it was internal and I need a new transmission, they didn't even drop the pan on it? I decided to hold on to my $3750. 00 for now and see if i could fix it. So far I have changed the fluid and filter and at same time replaced transducer and solenoid in transmission. Cleaned all battery post as they were kinda corroded. Checked the fuses and rely under the hood. Checked all the linkage and the kickdown cable at transmission and throttle linkup. all looks good and tight with no slack or play. All This didn't help! Pulled pan again and checked adjustment on rear band and it seems fine. This is the third time for the pan off and no metal particles found at all! Have to get a new gasket and filter before I put it back together again. Checked all the valves in the valvebody with small rod to make sure they move somewhat and not stuck. The only other thing i am going to try is to replace the drive output/speed sensor, figure it must be something in the electronic side since it happened so suddenly!



Any other suggestions would be appreciated! Truck has been like this for a week, really need to get it back rollin!

 

[BKenny]

Don,t let the dealership mess with it give Bill at DTT a call 1-866-504-4002 . He should beable to help you figure it out.

 

[rattlnrench]

Put an ohm meter across the output speed sensor terminals. I bet you'll find its open. I believe the resistance should be 2500 ohms. I've seen a few go bad including one on mine. Bill can definately help you also.

 

[Joe G.]

It's probably some sort of electrical problem. You should get some advice from an expert like Bill before messing with it any more. Might break something.

 

[MattAdams]

Update to my trany problem! Took rattlnrenchn's advice and checked the ohms of the drive output speed sensor and just as he said it was wide open!! Went to my local Autozone and picked one up for 24. 95 with tax! Came home and slapped it in put my new pan gasket on and filled her up. Took it for a spin and it shifted to second and third & OD with no problem at all!!!

Funny how its always the last place you would think to look! I did a lot of research about my problem and they all pointed to the govoner solinoid and pressure sensor. Never saw anybody with these symtoms and this sensor as the culprit but I quess when you think about it the PCM didn't see any speed so it didn't shift ,so only First gear!!!



Thanks for the replys and glad to know Bill is out there to help . I see his name mentioned a lot on several differant web pages dealing with dodge diesels transmission issues! Not quite ready for a new transmission yet but will give DTT a look see when the time comes! Thanks again for the help , glad I joined and am sure i'll need some tech advice in the future !!

 

[tractorface]

Way to go

Pretty dam upsetting the way the dealer handled bussiness. Many dealers could care less about thier customers. Really makes me . Would rather charge you for a new transmission than hire competent folks who know how to trouble soot. You should post the name of the dealer so folks can stay away. Bet they do that to a lot of people.

 

[RobertMiller1]

Confront the Dealer, Maybe the education will help the next poor chap...

 

[rattlnrench]

Glad it was something simple. I'm no "Expert", I don't know everything but I have been doing this for a living for 30 years. There could have been a code for the speed sensor in the computer but you have to look @ the right one. Your truck has 3 computers on it & they control different functions. The ECM controls the engine. The PCM Controls the transmission. The BCM controls body. They probably didn't find it @ Autozone because they were looking @ the ECM & didn't bother or didn't have the capability to scan the PCM. There should have been a code p1693 for a problem in a companion module but it's also possible to not set a code @ all. I've seen it both ways. The key here is to look @ the Datastream PIDs for anamolies, something that doesn't fit. In your case on a test drive it would show no output speed signal & therefore no governor rise. The governor rise on the 47re is simply a 1 to 1 in PSI to output speed. No speed signal = no rise = no shift. The transmission doesn't have to shift if you're not moving. I directed you to the speed sensor first because I figured you didn't have access to a scan tool capable of displaying the Datastream or gauges to test transmission pressures. I think Autozone uses a code reader tool only & probably a generic OBD II at that. The dealership should have caught the problem though & there is little excuse for that. Be aware though that a tool, the dealer should have the best, is only as good as the guy behind it.

 

[MattAdams]

Your right there the the scanner is only as good as the operator behind it!! Even if they found no code you would think that they would check the pressures ,then they would have known that it was stuck in First and not second. And yes I plan on a little visit with the service manager to let him know of this, because he may not know he has a untrained or lazy(may not have scanned at all for all I know) operator! Besides I deserve my money back or at least two free oil changes for such a way off diagnosis! At the very least it can only educate them that the customer is not as dumb as they think we are and yea it may save the next guy a big bill and unecessary work. Can only hope that that's not the way they do business and they try and get you for the whole transmission and all along they knew it was this sensor! Any way i'll see what they say on friday.

 

[CBowden]

rattlnrench--Where do I find the "Put an ohm meter across the output speed sensor terminals. I bet you'll find its open. I believe the resistance should be 2500 ohms. I've seen a few go bad including one on mine. Bill can definately help you also. " not sure where to find the output speed sensor? My 00 is experiencing sort of the same symptons, yesteray it started winding up to 2400 rpm before it would shift into a different gear and up to 2600 before it would shift to OD. Thanks... I am out of warrenty and do not want to take it in the shorts from the dealer. .

 

[rattlnrench]

It's a white or grey sensor towards the rear of the transmission. It has a 2 wire connector to it. Since yours is a 4wd I believe it's mounted on the transfer case adapter, drivers side. I don't think that's your problem although it could be. I would check the throttle cable @ the transmission. Have someone work the accelerator pedal to the floor while you watch the cable @ the transmission. It's the top lever with the small return spring hooked to it. Don't rule out the throttle valve in the valve body being stuck if the cable works correctly. A bad governor solenoid or pressure transducer can cause it also or wiring problems to them. You really need a scan tool & pressure gauge to check them. I would replace both if one is found bad while you have the pan off. Hope this helps.