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Manual TCC Lockup

Hey I have a question here for you guys, when you use the tcc lock to slow down when you are not towing does it do much? the reason I ask is I run pretty heavy with all my tools and material for work every day but I dont tow much, but every thing here in Pittsburgh is a hill and I hit some good ones every day, I go through front brake pads in 10-15000miles. So Im trying to figure out if this is worth doing for me cause any help on the brakes is great, my rotors are constantly warped cause it is near impossible to break them in properly here. Thanks guys.

Justin
 
Yeah, if you're in lock, you get some engine braking and can downshift - can't do that so well with a TCC that unlocks and free-wheels.
 
dracor85 said:
Hey I have a question here for you guys, when you use the tcc lock to slow down when you are not towing does it do much? the reason I ask is I run pretty heavy with all my tools and material for work every day but I dont tow much, but every thing here in Pittsburgh is a hill and I hit some good ones every day, I go through front brake pads in 10-15000miles. So Im trying to figure out if this is worth doing for me cause any help on the brakes is great, my rotors are constantly warped cause it is near impossible to break them in properly here. Thanks guys.

Justin
Click to expand...

A friend has a 01 ford with a banks exhaust brake and the TCC lockup slows down my truck alot better then his exhaust brake. I would think you would want a switch that isnt a constant on or a push button. That way like a exhaust brake you just hit the button when you want it on.
 
dracor85 said:
Hey I have a question here for you guys, when you use the tcc lock to slow down when you are not towing does it do much? the reason I ask is I run pretty heavy with all my tools and material for work every day but I dont tow much, but every thing here in Pittsburgh is a hill and I hit some good ones every day, I go through front brake pads in 10-15000miles. So Im trying to figure out if this is worth doing for me cause any help on the brakes is great, my rotors are constantly warped cause it is near impossible to break them in properly here. Thanks guys.

Justin
Click to expand...

Try Ceramic Pads. I use to piss through the fronts too (heavy like you).. Ceramics last forever it seems. Keep your rears adjusted. I've never had warped rotors.. Pretty sure I stil have the factory ones. Did you buy junk?
 
DieselSlug said:
Yeah, i cant remember what i was thinking typing this, i wrote it backwords. I also feel more power or grunt with it locked in. So when you lock up the converter should it be done @ 45mph and above due to strain put on the transmission?
Click to expand...

Reflashes lower that to 42 or so. I think its just to avoid engine bog, but with the higher fuel rates of the modified reflash it isn't an issue from what I read.
 
Ok im going out this afternoon after school to buy the 3-pole switch and wire it in. Along with putting on the summer rims and tires. This should be cool.
 
Guys- I am trying to do this mod today. I have a 2 position 3 pole switch ready to rock, but am not sure what GM calls "brown". There are a couple wires that look brown- one has a white stripe. There are 3 electrical connections on the drivers side of the 4L80E, 2 that sit one on top the other, and a larger connector behind it. Which does the brown wire come from?

FYI I have searched and have looked at Heath's write up. Pics would be awesome!
 
dracor85 said:
Hey I have a question here for you guys, when you use the tcc lock to slow down when you are not towing does it do much? the reason I ask is I run pretty heavy with all my tools and material for work every day but I dont tow much, but every thing here in Pittsburgh is a hill and I hit some good ones every day, I go through front brake pads in 10-15000miles. So Im trying to figure out if this is worth doing for me cause any help on the brakes is great, my rotors are constantly warped cause it is near impossible to break them in properly here. Thanks guys.

Justin
Click to expand...

The best thing the TCC lock does is give you extra MPH over 2200 RPM on a hill. TCC unlocked would just generate heat and slow down MPH: TCC locked will start to gain speed - towing a hill here at WOT with a 28'.

Transmissions are weak with regard to the compression braking 'overrun clutches' and the TCC itself clutch isn't that big. It can cause you issues under hard use. I would recommend a better torque converter with a bigger clutch, billet cover for the clutch to ride on etc. Stock will be fine, but, this is hard on a transmission's listed parts above. The TCC was designed for a few extra MPG and the over run clutches were not designed for compression braking at all - these are a separate set of frictions that is used for up shifting and driving the vehicle forward.

Why a locked TCC clutch will do better for forward speed than unlocked indicates a design problem with the OEM converter - too much slip I think.

When you come to a complete stop your brake pads and rotors are red hot. You need to creep a couple times while waiting at the light to move the red hot pad over a different part of the rotor. Otherwise you will heat treat a hard spot into the rotor where the pads are covering it. The rest of the rotor not under the pads cools differentially - quicker.

Now that you have serious hard spots in the rotor - THROW THEM AWAY!!! The cutting/turning tool literally bounces off the hard spots during the turning process. in less than 3K the pedal pulse will be back because that hard spot is still there. The only way to recover the rotors is by grinding them and these machines are hard to find.
 
JiFaire said:
You can't do this with OBD-II ... the TCC solenoid accepts only PWM signal, shorting the line to ground will force limp mode and error code.

If you want to lock an OBD-II tranny, you need a BD Autolok or BD Torquelok (can't remember which)... but that is what Edzzed has.
Click to expand...

Actually what I have is the B&M shift plus. http://www.bmracing.com/PRODUCTS/Transmission-Accessories-and-Kits/ShiftPlus-Electronic-Shift-Improver
Heaths computer essentially does the same thing, when I originally had the hp4 ecm put in I had about the firmest shifts possible but in the following days had soft shifts and after 50 miles I'd have hard shifts, turn the key off and it went back to soft shifts. Even took it into a tranny shop and they suggested I bring it back when I had hard shifts. It kinda came and went with whether I was gonna get firm or hard or even soft shifts. The B&M fixed that right up, I get consistent hard shifts ever since. One point to note is Bill kind of looked surprised when he drove my truck after installing the ecm. In subsequent conversations I should have told him I had a rebuilt tranny with a shift kit installed. So I guess I got double firm shifts. I dunno but I like it. Maybe if I upgrade ecm to work with the ATT I'll ask about tcc lockup. Ed
 
JiFaire said:
You can't do this with OBD-II ... the TCC solenoid accepts only PWM signal, shorting the line to ground will force limp mode and error code.

If you want to lock an OBD-II tranny, you need a BD Autolok or BD Torquelok (can't remember which)... but that is what Edzzed has.
Click to expand...
The difference between the AutoLoc and TorqLoc is that the AutoLoc automatically
controls the TCC lock up signal once it receives a power signal from the exhaust
brake switch and the TorqLoc has a manual position, automatic (or AutoLoc
position), and an Off position.
So, in comparing between the AutoLoc and the TorqLoc, the TorqLoc will force the
convertor clutch to lock up & the AutoLoc will only hold an already locked up
convertor clutch. When you ask for an overdrive to third gear shift, the TorqLoc
doesn’t wait for the computer to lock up the clutch, it sends its own signal to the
convertor clutch, and as long as you are A) above the set speed and B) the
transmission is hydraulically correct, [throttle pressure is applied], the TorqLoc will
force a lock up.
The AutoLoc cannot force a lock up, but can only hold it on deceleration. The
Chrysler transmission does not lock up in third gear, unless the overdrive is turned
off. Also, the Chrysler transmission won’t allow an overdrive to third gear downshift
if the TC clutch is locked up. This holds true not matter what system you are using
to hold the TC locked up.
While driving with the overdrive turned off, and the AutoLoc is turned on, the
transmission shifts from first to second to third, and then locks up.
Anytime after the lock up has occurred and you take your foot off the accelerator,
the AutoLoc will turn the exhaust brake on and hold the torque convertor clutch
locked until about 25mph when it will then turn off the torque convertor clutch.
When driving on the freeway in overdrive, the torque convertor clutch will be locked
up and the AutoLoc turned on, if you release the throttle the AutoLoc will apply the
brake and hold the TC clutch lock up.
To increase the amount of retarding horsepower, turn off the overdrive and the
AutoLoc will sense this signal and cut the signal that’s holding the torque convertor
clutch applied, the transmission will then downshift into third gear. At this point you
should apply throttle pressure until the factory computer says everything is okay and
locks up the torque convertor clutch.
As soon as this happens you should remove throttle pressure and the AutoLoc will
turn the exhaust brake on and keep the torque convertor clutch applied until you get
down to about the 25mph mark. The set speed is adjustable, one can set it for a
higher mph, so you don’t have to worry about remembering to turn off the overdrive
or lower if one has 4:10 gears.
Now suppose you’re driving along, overdrive is on, the AutoLoc is on and you need
to make a stop or slow down, but don’t need the extra retarding horsepower of third
gear or you don’t have time to wait for the downshift, applying throttle and waiting for
lockup, (this would all take about 4-6 seconds) and you don’t want the shuddering that would occur when you have a locked up torque convertor clutch & you’re going
to be doing less than 35 mph in overdrive.
You can do any of the four following actions to cancel out the system: 1) turn off the
AutoLoc switch, 2) turn off the overdrive, 3) lightly step on the throttle pedal, or 4)
pull the gearshift lever down into second gear. Turning off the overdrive or the
AutoLoc are the best of the four options.
Now enters the TorqLoc, it should only be used under light throttle applications. No
matter whose torque convertor you are using, the converter clutch has only so much
holding power & if you exceed this you will start to slip the clutch, thereby starting
the demise of your convertor clutch.
An example of when to use the TorqLoc position would be when you are on a
winding road where you are on and off the throttle a great deal and you don’t want
to keep locking and unlocking the convertor clutch. The TorqLoc will hold the
convertor clutch locked up, preventing that from happening.
You must keep in mind, while doing this, that if you apply too much throttle pressure,
especially at the lower rpm band, you may start to slip the convertor clutch. A
general rule of thumb when holding the convertor clutch locked up is no more that 1
lb of boost for every 100 rpm of engine speed.
 
I want to do this mod but wish to splice the wire near the computer (under the dash) as opposed to under the truck. There are a couple/few brown wires and 3 connectors. Can anyone tell me which wire/connector it is??
 
Thanks Big Art- I found C11 just as you sent this! But now I at least know I am on target. HOWEVER... I am REALLLLLY confused on what switch to use. I bought a 2 pos 3 pole switch and thought I was good, until I read that post...
 
A single pole double pole switch is all you need, but I used a double pole, double throw switch. I used the second pole for LED lights to be a quick visual reminder for me which position the switch was in. 12V+ power goes to the second pole's center lug on the back of the switch and the positive side of the LED goes to the the corresponding lug of the second pole. Ground the other leg of the LED. I used green for normal TC operation and red for TC lockup operation.

Don
 
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