TCC Lockup devices

[jeffreydmet]

Does anyone know of anyone that makes a device to lock the torque converter clutch on command and in sencond gear? What I would really like to do is control the transimsion totally in a manual mode. I pull about 5000lb about 80% of the time and I keep thinking about all of the fuel the auto waste when you are pulling and the TCC is not locked up. Sometimes its 20% of the power the motor is making. Before this truck I have always towed with a manual transmission and I have to say I think the automatic is a joke to pull with. Anybody want to trade trannys? My truck is a 99 K3500.

[HowieE]

Search this topic "4L80E lock up in 2nd gear" and you will see my coments on the BD Torque Loc and how it can be used manually. Keep in mind that if used in auto mode you will set a code with your trans.
There are several other posting on this point but this is the most recent.

[jeffreydmet]

Howie, What functionality does the BD unit have in manual mode? Does anybody have an idea what would happen if one were to splice a switch into the TCC solenoid valve so that it could be manually actuated?

[rjschoolcraft]

I wrote an article for the Diesel Page Members area on the TorqLoc. There is also a lengthy thread on this forum. See these two resources for more information.

[HowieE]

Using the BD on the later transmissions as a manual control has advantage over just putting a switch in the circuit.
There are 2 modes I use it in manual while towing.
In areas such as short hills or traffic where speeds are in the 40 to 55 mph area I will drive in 3rd. with the BD engaged. In this mode no codes will be set and the BD will engage and disengage automaticaly against the vhecial speed sencor where as if just a switch you would have to selecting engage or disengage every time the truck crossed sa 35 mph. In this setup the convertor is locked at speeds above 35 mph and I have full advantage of the exhaust brake in this traffic.
On the open road and in OD I set the BD on once above 55mph. The only thing I have to be mindfull of is that if I drop below 50 mph and forget to release the BD I will go into limp mode and set an 0742 code when accelerating.

[Turbine Doc]

Howie E,

Have you looked at the possibility of tieing the Torque lock to the cruise control off switch, is that doable, then it would go off like CC brake applied goes off. Does this device help in dyno runs

[HowieE]

Ther is a provision built into the BD to wire it to the CC. The problem there in my case is I have an exhaust brake and when the CC is engaged the throddle pedal is completely off which would engage the exhaust brake. I have accidently set the CC while the BD is on, that realy is like hitting the wall. The engine goes to full throddle against the exhaust brake, the EGT goes through the roof and jet black smoke comes out. Not a goo idea.