Dodge RamCharger Central banner
1 - 20 of 21 Posts

·
Registered
Joined
·
157 Posts
Discussion Starter · #1 ·
Hey guys, so after doing some testing to figure out what is going on with my transmission. I have found that the torque converter is not locking up on the highway but the trans is going into overdrive and shifting into 4th gear. I checked the 3 wire connector on the transmission and the middle wire has 12 volts. I was wondering what the possible causes could be for the torque converter not locking up. Thanks.
 

·
Registered
Joined
·
13,500 Posts
on a P/C click on photo it should enlarge to read , far left column with all the x 's is will not engage possible problems 
 

Attachments

·
Registered
Joined
·
157 Posts
Discussion Starter · #3 ·
Thank you for the help. Is there a way to check the lockup solenoid and relay to see if they are working properly? Also where are the lockup solenoid and lockup relay located? Thank you. Also this is my gas 93 ramcharger 5.9L, I forgot to mention that in my first post.
 

·
Administrator
Joined
·
62,267 Posts
Its the engines computer that controls it. The relay is located inside the transmission, with no relays between the computer, and the tranny. What makes you think it is not working?
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #5 ·
Im pretty sure I know the torque converter is not locking up because it started running a much higher rmp on the highway. I thought maybe at first it wasnt shifting into 4th gear but it definitely is. Then I thought it wasnt going into overdrive but when im on the highway and I hut the OD switch the rpms raise so I am pretty sure it is going into overdrive. By process of elimination I figured it must be the torque converter not locking that is causing the rpm to stay high on the highway, but if you have another idea I am open to them. Thanks
 

·
Administrator
Joined
·
62,267 Posts
How much higher? A typical unlocked torque converter above its stall speed, will generally be less then 10% slip. So cruising around 3000 RPM, would be less then 300 RPM.  I have never seen (does not mean it will not happen) a Torque convertor clutch just up and die. Generally you will get a lot of shuddering for quite a while before it goes out completely.

Oh yea, in your tranny, 4th gear is overdrive. So if you think you are feeling 4 shifts, the 4th could be the TCC locking up.
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #7 ·
Yea I definitely feel 4 shifts but what is not hapening is usually on the highway at 45 MPH when the torque converter would lockup the rpms would drop from about 1800 rpm to 1200 (it was very noticible) now on the highway at 55 MPH the truck is running at 2100 RPM
 

·
Super Moderator
Joined
·
13,934 Posts
...once it's in OD and you're cruising along...if you press the pedal a bit (but not enough to downshift) does the engine rpm come up any at all?  If the rpm's come up a bit (without any corresponding increase in speed) then the lockup is not functioning, but if there is no engine rpm change then the LU is working
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #9 ·
Thank you for your response. Yes if I press the gas the rpms do come up but the truck doesn’t speed up at all until it downshifts. This is another reason why I believe the lockup is not functioning. Is there a common problem with these trucks that cause the lockup to stop functioning. Thanks
 

·
Registered
Joined
·
13,500 Posts
IF you had a 3 speed with a lock up converter , the '93 manual shows a separate relay under hood BEHIND
( toward the firewall) the driver side hood hinge ( EEMC). BUT it s NOT likely you have a 3 speed , and the '93 factory book shows the 2 internal transmission solenoids getting power from the asd ( truck runs so it ain't that relay bad ) , solenoids are just under trns oil pan , on valve body .  normally when mine shifts , it actually sounds and feels like 5 gears , 2 more after 3rd , rpms drop each time ( 4th and LU ) 
you could check to see if the LU solinoid was getting ground but you would have to make a "break out box" for the 3 wire vertical connector on the trans ( vertical NOT horizontal b/u neutral safety switch wires !) the center wire in that connector is positive power , goes to both solenoids , while the other 2 are their respective grounds from the PCM color codes will tell ya which is which . you will have to wire your tester in the cab , and drive it , power your test light , find 2 grounds after 42 miles per hour warm engine , and its electrically working TO the trans . after that it could be a stuck valve body or a bad solenoid , or bad converter .....
 

Attachments

·
Registered
Joined
·
157 Posts
Discussion Starter · #11 ·
Thank you for the response. That is exactly how mine used to feel. The lockup felt like a 5th gear on my 4 speed trans. Now that shift-like feel is defintely not there. So can I test the solenoids by running a ground from the battery and then running wires that tap into the wires on the connector to see if they actuate on the highway?
 

·
Administrator
Joined
·
62,267 Posts
Yes, you can. Remember the center connector gets 12 volts, and the two outside get grounded to activate. I do not recall which is which, but when you are cruising, and in 3rd gear, actuate one, then turn it off, and do the other. Not sure what would happen if you start to slow down in overdrive. It can be bad on the TCC if you try to come to a stop with the clutch engaged.

Check your engine codes, could be something else bad, that is keeping the computer from signaling the TCC
 

·
Registered
Joined
·
13,500 Posts
what I might do :  first I'd push the od button after it shifted up , see if it IS the L/U that failed , cause the way the rpm's drop and the truck speeds up , I couldn't tell you which was which , gear or L/U both seem to do a gear ..I have one truck that will pop out that button on  bumpy road occasionally / rarely enough I don't care why .
then I would look at the wire diagram , the eemc solenoid wire color . unplug the harness at the trans , SOMEhow connect a lead to the center pin , up thru boot to my test light , I'd connect a 2nd lead to the eemc pin , up thru the boot , drive the truck , warm , above 42 mph , cruse light / throttle  , touch test light ends to the 2 test leads , should light test light . remember standing still , engine running , the center pin/wire is positive , the 2 outer pins will be nothing , not ground , not power . when the pcm ( computor ) decides its time for od or l/u it sends ground to the outer pins / wires  , so your looking FOR a ground NOT a positive .. if your light lights your harness and pcm control works ...

  an option : buy a male connector wire end ( Napa) disco harness from trans plug in your test connector , wire a fuse from ? cigar lighter positive  power  to center wire , drive truck apply ground to either outter wire see if it shifts . and or locks up , then you know trans /converter works
  a pita fer sure , and yes by all means check blink codes first ,, damd good idea !
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #14 ·
So I took the truck out on the highway again and I pressed the overdrive off button the truck was definitely in overdrive because when I pressed the button the rpms went up about 300 RPM without changing the throttle position, so I am almost positive the overdrive is working. I flashed the codes and the codes I am getting are 22, 37, and 45. Would any of these be signaling a problem with the lockup? I plan on testing to see of the computer is supplying a ground to the lockup today. Thanks.
 

·
Super Moderator
Joined
·
13,934 Posts
...when "4th" gear engages...if the engine rpm's don't 'lock' to match the speed (no converter stall at all), then the lockup is not functioning for whatever reason.  If the rpm's do 'lock' then either lockup is occurring, and it is possible that the OD is also occurring at the exact same time (same signal).  If there's no 'lock' but you're getting 4th gear then OD is kicking in but not lockup.

So long as it is an RH transmission (not an RE) you could put the lockup on a toggle switch (to ground) - at least I know you can on a diesel application, and bypass all of the factory electronics all together.  Might be tough getting the OE wiring/computer/sensors to function correctly once they've become faulty...
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #16 ·
Thank you for the response. I think that is the exact problem I am having. I am going to do the ground test tomorrow to see if the solenoid for the lockup is bad. I would rather fix the lockup solenoid or relay before I hardwire it to a toggle but in the end if the repair is too involved thats what ill do. Has anyone ever replaced the lockup solenoid on an RH is it a very involved process?
 

·
Super Moderator
Joined
·
13,934 Posts
have to pull the pan and the valve body - the 2x OD and LU solenoids are on a bracket attached to the valve body - replace, reinstall, refill.  Messy, greasy grimy work, but there's no other way.
 

·
Registered
Joined
·
13,500 Posts
37 trans lock up circut problem . check the external wiring , then if that is ok the internial and coil .
 

·
Registered
Joined
·
157 Posts
Discussion Starter · #19 ·
Hey guys so update I have solved the problem. I had my buddy come over he has a scan tool and we verified that the torque converter solenoid and relay were working. We saw the code for the engine coolant temperature sensor so we checked the sensor and it was clearly not functioning and was actually broken off by the connector side. 20 bucks later and about 15 minutes we got it replaced cleared the codes and the lockup converter and everything is now working beautiful. I am so happy that I didnt have to start pullling apart the trans or tracking a wiring problem. It pays to have friends that have the right tools. Thanks again for all of the help guys!
 
1 - 20 of 21 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top