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TC lock up thread

338K views 907 replies 263 participants last post by  Tuneingr 
#1 · (Edited by Moderator)
guys i want to put together a few things to help our members out. we have a lot of people having lock up issues lately. i plan to put something together in the troubleshooting thread. :thumbsup: if there is a vendor that has a product on the forum and you have used it please comment and post a link. if anyone has a pic of a wiring diagram or anything like this please post. thanks guys :yourock:

link to one type of fix

http://www.cumminsforum.com/forum/9...cussion/269858-bd-noise-isolator-install.html

HI GUYS: I HAVE COPIED THE ENTIRE THREAD INTO A "WORD.DOC" AND WILL FORWARD TO YOUR EMAIL ADDRESS UPON REQUEST. IT WILL BE EASIER TO READ. UNFORTUNATELLY THE FORMATTING AND INDIVIDUAL POSTER WAS LOST. YOU CAN TRACK THE POSTER BY LOOKING AT ORGINAL POST.
AGAIN THERE IS NO ONE FIX CURES ALL.
THANKS,DOZER12216
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#276 ·
quick question please help. i just noticed this happening yesterday and i can fix this i need to do it asap. i noticed that during cruising speeds my truck starts to "hop" as if i had enormous tires that needed balancing but the "hop" duration is a little longer and feels like my driveshaft slows down for a split second. i dont know how else to describe it but im hoping this is the tc and can be fixed easy. when i put my adrenaline on i noticed it wasnt wanting to show the gear i was in and the padlock, which im guessing represents the TC is always sperratic, locking and unlocking constantly. i removed my passenger battery a few days ago to mount it somewhere else. the wire from the alternator to that battery like u talked about, i hooked it straight to the battery ground cable(engine block ground) that is still where the battery use to be. there was also another wire on the ground terminal that went into a wire harness. do i need to completely seperate the alternator wires fromt he rest of the wiring to ensure this problem doesnt happen again?
 
#4 ·
Don't beleive there is a one fix cures all repair. Suggest starting with grounds and power connections. Clean rust and seal with grease.
Next have batteries individually tested at parts store and have alternator bench tested. A inspection of brushes for grease on slip rings would be in order while off.
Try shielding the wiring at alternator. Wrap aluminim foil around wiring for 18 inches of so, back toward engine. Taking tape and couvlute off and wraping alternator wires (3)with very small wire for 18 inches or so and then ground this shielding wire. Do Not short the shielding wire to alternator wiring. You can now rewap the convlute for nice apperance.
Some other items of intrest. APPS reset mayh be of benefit. Killing memory by disconneting all battery terminals and toughing a positive lead to a negative. You are shorting the wiring, NOT the batteries. This kills memories and fault codes.
A poorly adjsusted brake switch or erratic speed sensor need mentioning as a possibility.
A condenser (radio supression condenser from old Chrysler ignition coil) housing mounted to alternator frame with the lead connected to alt. output terminal is effective in reducing alternator stator wiring imbalance and internal condenser issues.
These are very low cost repairs and have been effective. The tranny specialist also offer various supression fixes and rewiring kits, but are expensive in most cases. Some have success with kits and some don't seem to, is my take on them.
A worn out torque converter may be the culprit also.
 
#5 ·
Don't beleive there is a one fix cures all repair. Suggest starting with grounds and power connections. Clean rust and seal with grease.
Next have batteries individually tested at parts store and have alternator bench tested. A inspection of brushes for grease on slip rings would be in order while off.
Try shielding the wiring at alternator. Wrap aluminim foil around wiring for 18 inches of so, back toward engine. Taking tape and couvlute off and wraping alternator wires (3)with very small wire for 18 inches or so and then ground this shielding wire. Do Not short the shielding wire to alternator wiring. You can now rewap the convlute for nice apperance.
Some other items of intrest. APPS reset mayh be of benefit. Killing memory by disconneting all battery terminals and toughing a positive lead to a negative. You are shorting the wiring, NOT the batteries. This kills memories and fault codes.
A poorly adjsusted brake switch or erratic speed sensor need mentioning as a possibility.
A condenser (radio supression condenser from old Chrysler ignition coil) housing mounted to alternator frame with the lead connected to alt. output terminal is effective in reducing alternator stator wiring imbalance and internal condenser issues.
These are very low cost repairs and have been effective. The tranny specialist also offer various supression fixes and rewiring kits, but are expensive in most cases. Some have success with kits and some don't seem to, is my take on them.
A worn out torque converter may be the culprit also.
correct dozer :thumbsup: this is useful info to everyone. this is why i wanted different people to post their ways things work. a variety of solutions for multiple problems is needed. thanks dozer
 
#176 ·
K so i installed the TC lockup switch and Everything was going good last night then this morning i started my truck and started it with the tc lockup switch on and it through the relay code and the converter electric signal code. do you think this is because i had it on when i started it? When i started it all day yesterday it wasnt on and it didnt through a code.
 
#8 ·
have your batteries checked. they have to be in good condition. even if your truck starts fine one could be marginal and cause problems. batteries are big noise filters. electrical noise is what causes these trans.tc problems. this is what i as told by Bill owner of DTT transmissions. it worked for me, it might for you. also a noise filter from DTT.
 
#58 · (Edited)
Ok so still yet to find a fix for mine if anyone has any ideas here is a list of every thing ive tried.

Wraped ground wire "blk/org" in aluminum tape, replaced both batteries, replaced alternator, check and cleaned every ground, tried noise filter, tried both suncoast and ats fix and reset the apps numerous amounts of times.

Any other ideas to try would be great. Thanks nathan
 
#10 ·
the instructions from the ats link don't work on my truck. The only thing that it did was keep my transmission from going into overdrive...I'm thinking about trying the suncoast one tomorrow to see if it works.
 
#11 ·
Well, I am in the same boat. Tranny wont shift into 4th after doing the ATS fix. Any other ideas out there, before I drop the big bucks and run it into the shop.
 
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#12 ·
My TC Lockup issue is solved by applying dielectric grease to my alternator harness plug and replugging back in. Don't know why, but it works every time. I keep my terminals clean also.
 
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#13 ·
oddly enough i began having a lock up problem between 40 and 50 mph right after the first oil change i did on my newish truck, the problem went away after a while and tonight i did my secound oil change ( i have owned the truck for about 2 months ) and the problem has started again. i went to school for diesel and i am getting pretty mad because oil changes and torque converters should not effect eachother, please tell me what the hell is wrong with this thing and why the problem only comes back when i do an oil change. coincedence??
 
#18 ·
As I said in my other post, "applying dielectric grease to the alternator harness plug".......Maybe when you spin off your oil filter, you are moving that plug around on the alternator....its very close. Just a thought !
 
#14 ·
Hmm, everyone seems to be having this issue between 40-50 mph. I've been having TC lockup issues between 30-40 mph. Is this basically the same thing?
 
#15 ·
Mine will do it pretty much as soon as it shifts to OD and for about 10 mph after that, then clear up and go away. Only seems to do it at those speeds......RPM a contributing factor? I don't know.
 
#16 ·
Ditto on my truck... when it shifts in to OD (45-50)and then locks it LOCK/UNLOCKS untill I get to 55. IF I lock out overdrive it does the same thing in 3rd just after it goes in on light pedal. I cleaned the ground strap at the PCM and that worked for a while, I guess I will do the SunCoast fix next.
 
#17 ·
I did the suncoast methood and I have no complaints. I live in Ft Lauderdale area, so there is alot of traffic for the most part of every day.Light on the throttle unless I am letting everyone behind me know I have Cummins. I would be driving along and lock/unlock/lock/unlock.......after the suncoast methood........when it locks....it locks...light or heavy throttle.
 
#21 ·
I have a similar problem with my truck. I don't think mine is completely unlocking like it seems others are. When it shifts to OD for about 10 MPH 50-55 I get a very slight shuddering. NO change in RPM just feels like I am on a bumpy road. It is worse closer to 50. Is this the same problem???:confused013:
 
#22 ·
Another issue that shows up in this area is a torque converter that cannot hold the torque and slips(shudders) for a few seconds. Sometimes this is result of ATF being dead and needing changing. However it does not take long to fail converter clutch. This happens most frequentlly with modded engines and the chip turned on. The general clue on this one is you are on the throttle some. These modded engines make tremendous torque in the 1600 -2200 RPM range that overpowers a stock converter with stock valve body. So a performance converter and valve body is generally a good bet as part of improved power upgrade path.
 
#24 ·
I just finished setting up my APPS and doing the ATS transmission wiring fix for eliminating the 4th gear hunt. However after doing both fixes my idle speed is @ 1400 RPM. My Initial APPS voltage was .446vdc. the tag on the sensor was .591vdc. I was attempting to get 1.2 - 1.5 vdc as suggested in a set up article on Geno's Garage. I followed the correct reset procedure for the APPS. I've driven the truck around a bit but it hasn't thrown any codes and hasn't adjusted the idle down on its own as yet.

Will this idle correct it self from a learning cycle? Or should I readjust the APPS voltage down?
 
#46 ·
Well this was what I originally did. I did reset my APPS voltage back to match the tag on the sensor (.591) Idle normal again. Also cleaned battery connections and put dielectric grease on them. Helped for a little while but problem came back.

Next I did the ATS wiring mod. Again helped for a little bit but shuddering came back. Next installed RFI noise filter from TRNW on alternator. Problem came back.

Got another RFI filter and installed on the APPS signal wire. Also wired up a TC lock up switch (this should force the fix when engaged).

One thing I did notice, when the problem would resurface after `fixing`it was usually raining. Well have to see if it returns (whin not using the lock up switch).
 
#25 ·
#28 ·
Hi all, I just bought my '02. The truck came with a "diablo power puck" I think it's called. Not sure how much of a upgrade that is but I also get a shutter. I bought the truck to tow my race car & trailer which weighs about 10K. When I tow the trailer is when I really see the shutter, especially if I'm trying to stay at 70mph. If I drive the truck harder the problem isn't as noticeable.

From the earlier post that I read it sounds like I need a converter, which kind do you guys recommend. Is the power puck a good thing to leave in, I like the power.

I also have one other weird thing that the trans does. Sometimes it will not shift into 2nd until the RPM is like 2600 & other times it will shift normal. I've seen it shift late like this for up to a week but I've also seen it shift normal for a week. Any Ideas?

Thanks Glenn
 
#908 ·
Hi all, I just bought my '02. The truck came with a "diablo power puck" I think it's called. Not sure how much of a upgrade that is but I also get a shutter. I bought the truck to tow my race car & trailer which weighs about 10K. When I tow the trailer is when I really see the shutter, especially if I'm trying to stay at 70mph. If I drive the truck harder the problem isn't as noticeable.

From the earlier post that I read it sounds like I need a converter, which kind do you guys recommend. Is the power puck a good thing to leave in, I like the power.

I also have one other weird thing that the trans does. Sometimes it will not shift into 2nd until the RPM is like 2600 & other times it will shift normal. I've seen it shift late like this for up to a week but I've also seen it shift normal for a week. Any Ideas?

Thanks Glenn
Look at the training fluid and see if it's clean or middle of it. Sounds like a clutch shutter to
me
 
#29 ·
81 Charger; Looks like it has been charged harder than it can stand. In addition the erratic 2nd gear shift is another sign of living in abuse lane to long.
If you are lucky, a tranny service with new fluid and band adjustment might buy you some time. Otherwise a performance converter and valve body along with tranny overhaul is upon you. LOL
 
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#31 ·
so as yall guessed im in the same boat as everybody. BUT im on the wall now on doing the ats fix bc some of yall say it works and 2 others say it wont let you shift into od AND makes it idle @1400! is there a common mistake i should make sure i dont do?
 
#32 ·
no luck

Tried the tc grounding switch and jumper, cleaned and greased the input plug on the tranny checked voltage to it...still no constant lockup... Shouldn't the switch keep the tc from locking up at all when it's not grounded? Any7 ideas?
 
#34 ·
Tried the tc grounding switch and jumper, cleaned and greased the input plug on the tranny checked voltage to it...still no constant lockup... Shouldn't the switch keep the tc from locking up at all when it's not grounded? Any7 ideas?
From everything ive researched the lockup switch should do the job unless the t/c is on the downhill.. Someone correct me if iam wrong cause iam gonna install the switch soon on mine as well to try once again to sure the lockup issues on mine that i havent been able to cure in 3 yrs..
 
#35 ·
First Crisis Averted

Just wanted to say thanks to all who have posted their knowledge here. Just got my truck about 3 weeks ago and it started searching for a gear at about 35 MPH earlier this week. My first thought was that I had just figured out why it was traded in - transmission problem. After some research on this site I was led to this thread.

While walking out to the truck with a roll of aluminum foil (and praying no one would stop me to ask what I was doing) I still thought this was crazy, but I am now a believer. Got home today after 300 miles through the mountains and it worked great.

Thanks again.
 
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