TQ Lock Up problems

[LostSoul]

I have a rebuilt trans in my 1995 and I have had nothing but issues with the lock up on the Torque converter. The people that originally had this thing had butchered some of the wiring, I replaced the Orange with black chaser from the main plug down to the OD plug on the transmission as I was not getting signal through the wire. Now the jumper has power, but I still have no lock up. I am wondering what else controls the lock up, (ie) the Kick down or anything like that? I am also wondering if I should hook a wire direct to power on a switch and see if that makes a difference by eliminating the PCM. If you guys have any ideas I would appreciate it.

 

[averagef250]

The PCM GROUNDS OD and lockup to control them. You can put OD and lockup on switches, run them off hobbs switches off the gov tap or leave them stock with dodge pcm.

 

[LostSoul]

My unit had the Orange with black chaser with no power getting to the tranny, I fixed that and it has not given me back Lock up, but I am getting OD. I can only assume then that the PCM is not doing its job of grounding the Lock up. What are the chances that I am getting Lock up in third and not getting 4th at all, I am sitting about 1800 RPM at 100K or 63 MPH. I know when I did get what felt like Lock up, I would see a drop of about 250-300 RPM and the truck was like a totally different machine, it would pull up hills like there was nothing there but flat ground.

 

[thirstyram]

Go to the TST wesite (owned by an ex cummins engineer.) he tells how to control lockup with a toggle switch betweed the orange/black wire to ground. He also removes the relay and makes a jumper wire between two terminals. then throw your relay in the glove box and you're done!

 

[LostSoul]

I hit up the site and after a bit of looking found myself some good info to have. I appreciate the help very much, now to give it a try.

 

[thirstyram]

glad it helped.

 

[LostSoul]

I grabbed a Toggle switch today and did a test. Sure enough the thing works like a char. The only thing I am wondering is why it tries to get into 4th so quickly, it is not holding the gears long enough to take advantage of the Lock up in anything but 4th. Could the kick down cable be an issue or is there something else that I should be looking at to hold it in gear? The other thing I find interesting is, the OD button will not kick the truck out of 4th when the toggle is switched, is this normal?

 

[Pipeliner_86]

I grabbed a Toggle switch today and did a test. Sure enough the thing works like a char. The only thing I am wondering is why it tries to get into 4th so quickly, it is not holding the gears long enough to take advantage of the Lock up in anything but 4th. Could the kick down cable be an issue or is there something else that I should be looking at to hold it in gear? The other thing I find interesting is, the OD button will not kick the truck out of 4th when the toggle is switched, is this normal?

Yes, this is normal. The BEST way to set up a toggle switch for the lock-up convertor is a 3-way toggle. 1 position is locked, the next lets the computer control lock-up and final position is open, or no-lock. Since your computer isn't properly controling lock up this wont work well for you. But once you throw the switch into lock, the trans will lock the convertor so long as your are in second gear, then it will charge thru the gears really fast untill in overdrive.
A good addition to the lock-up switch is the variable resistor control for overdrive http://dieseldatabase.com/read.php?id=54
This may help your computer control lock-up, since the tps plays a part in lock-up. This mod eliminates the tps with a $5 part from radio shack. I've installed 2 of these on past trucks, along with convertor 3-way lock-up switches and they're an awsome combination.
If I can find the tech articles with diagrams I'll post them.

 

[Pipeliner_86]

I found the tech write up here--> http://www.tstproducts.com/Torque Converter Lockup Switch.pdf

This is a good referance site for anything you can imagine about the cummins trucks. Here http://www.cumminsforum.com/forum/94-98-tech-articles/21261-tech-article-links.html

Enjoy

 

[LostSoul]

Thanks a lot for the help, I have some reading to do lol.

 

[Iroc12valve]

Mine shifts from 2000 RPM @ 75 kph to lock up: 1750 RPM @ 75 kph
holds until it hits 80 KPH (about 2 seconds) and then business mode
1450 RPM @ 80 kph and straight-shot to 120 and a speeding ticket

 

[LostSoul]

I engage mine at about 80K if I do it in second, it flashes through the gears into OD anyway. Once I engage the switch, it is a totally different truck and will do the same thing 80-120 in no time. The one thing I love about it is with my trailer and Zuk on with it in OD and locked, it does not drop even a little speed on a hill. I have 4.10 in it and it runs at 1700 RPM at 100K. I just about died the other day when my buddy's with first gens were talking about what they run. The 89 runs about 2800 RPM at 100K with a 727 and the 92 hits 2200 with a 518 in OD.

 

[thirstyram]

Mine shifts through the gears real fast too. I just thought something was wrong with my truck. one time I engaged the switch off the line, then full throttle thru the gears. it shifted where it should have, accelerated like a ***** ape, but shifted so hard it jarred my teeth! Me thinks very ******* trans. don't recommend it, but what a ride!

 

[Pipeliner_86]

If you guys happen to be running a stock convertor, you're gonna burn it up in a hurry with all that lead foot action. I'm sure you already know this, but it's worth saying again....Dodge torque conertors are junk! They cannot handle any more HP than stock output, and even then they're usually shot by 80,000 miles. The transmissions can be built to take the abuse, but you gotta but an aftermarket TC, like a suncoast or ats triple disc. My opinion, an allison should've come stock behind a cummins when orderd with an auto, but I don't even like auto's to begin with. I'll take a bolt action anyday over automatic, and the power that a manual trans puts to the ground over an auto is night and day differance.

Man I miss my cummins

 

[thirstyram]

Not to mention broken shafts. I'm currently running a Spec Rite tripple disc,steel stator. 90% efficient. What a differance from stock! Now she accelerates almost like my neighbors 5 speed. I've also got the trans. built to the max except no Billet shafts so I've still gotta be careful not to twist those off. I did go with a laminated flex plate though. The local diesel shop says thats all he runs on his race truck (600 + HP).