TC lockup Mod.

[Goofyexponent]

Seeing as how my TC has given it's notice about quitting the organization, and based Jaki_IN's and Fozz's suggestions I went ahead and did the TC lockup mod today.

I am impressed at how the E4OD works without that lockup BS trying to lock and unlock the TC all the time. I have a switch under a BIG RED COVER saying T.C. LOCKUP and I made it VERY clear to the ONLY two people that will ever drive the thing without me....under NO circumstances, even if god himself says to, DO NOT TOUCH THAT SWITCH...purely because if they flick it and forget about it or flick it too early....bye bye transmission.

For those of you who don't know what a Torque Converter Lockup Modification is....I suggest you check it out and do it!

I will be doing the relay mod as RLDSL has...I touch the brakes and she unlocks....giving mye time to have that switch knocked off again.

 

[LCAM-01XA]

Uhm, RLDSL has a ZF5 with a brownie behind it

 

[Goofyexponent]

Uhm, RLDSL has a ZF5 with a brownie behind it

Damn! Sorry, but then who am I thinking of that has the relay inline with the TC mod?

 

[Goofyexponent]

OH, it's you! Is the relay install that hard to do? I am pretty good with wiring...I got to be...I got to fix all Ford's mistakes! Next is the headlight relay mod!

 

[LCAM-01XA]

Lol, I see you're living up to your username The relay is a piece of cake - first you gotta have the right relay tho, you need one with 5 terminals, which you should be able to buy at about any place that sells electronic components. You need the 5-pole relay because it's actually switching the current flow between terminals #87a (powered when relay is disengaged) and #87 (powered when the relay is engaged), if you leave terminal #87 open you end up with an interrupting relay. Right now you probably have the wire from the TC to the switch directly, to install the relay you cut that wire at a suitable location and add two spade connectors to the now-loose ends and you plug them onto terminals #30 and #87a on the relay, it shouldn't matter which end goes on which terminal but just as a good measure plug the end from the TC onto #30 and the end to the switch on #87a. Leave terminal #87 open, nothing connects to it for this job. Then run a wire from your brake switch on the pedal (one side is always hot on that, you want the other side, else your converter will never lock), add a spade connector at the end of the wire, and plug that onto terminal #85 on the relay. Then ground terminal #86 on the relay with another wire with a spade connector, there are several grounds bolted next to the fuse panel so you can use that location if you want to, or alternatively the steering column's aluminum brace is a great ground too. So now what happens is the current from the TC enters the relay from terminal #30 and exits it from #87a (those two are normally-closed when there's no trigger signal to the relay), this is your slave circuit. Then when you step on the brakes a tiny amount of current flows from the BOO switch in the relay through terminal #85 and into ground through terminal #86, this is your master circuit that energizes the relay to switch the slave circuit's exit point from terminal #87a to #87, but we left #87 empty so essentially it switches current from the TC into nothing and thus interrupts current flow and results in converter unlocking regardless of what position your big red manual switch is in. Then when you let off the brakes the relay's master circuits powers off, the slave circuit switches exit points from #87 back to #87a, and restores continuity from the TC to your big red manual switch.

 

[BlueBreadTruck]

very nice. Since you just did this, how do you locate the wire from the computer? I need to find a writeup

 

[LCAM-01XA]

When I did mine I just found the wire in the transmission harness, much easier to locate it there (yellow wire with a purple tracer, or was it a purple wire with a yellow tracer, I think the latter) - I cut that halfway between the frame rail and the transmission and then pulled the end coming from the PCM out of the harness where it runs along the frame rail and fished it in the cab through the grommet for the speedometer cable, then the short end attached to the transmission I extended with more wire (ran that one through the harness loom as if it's factory) and fished that in the cab through the same grommet as well. The end from the PCM got the 22k resistor treatment, the extended end from the transmission got the relay and the manual switch.

 

[tractorman86]

Lots of people do it to diesel trucks, but would a Gasser get any real benefit from this mod?

 

[Goofyexponent]

I think so! My trans runs WAY better with the TC unlocked until I get up to speed.

Thanks a LOT LCAM-01XA for that little writeup, that should be added to the tech section for sure.

 

[Goofyexponent]

E4OD lockup Mod

For those who would like to convert there lockup to a manually controlled status via a two pole switch, the following will apply.
I post this information for peeps that Who do not want to entirely reverse engineer thier lockup circuit. Thus was the case on one of the vehicles brought to me. This mod was performed and works like a charm on an ambulance that had intermitten lockup problems. Intermitten lockup causes heat and convertor failure. Ideally in this situation the vehicle could be diagnosed by Ford with minor difficulty. However, It is my luck as is some of yours that the problem cannot be picked up my scanning the rig for faults. Poor grounds or dirty connections do not display themselfs on scanners. This vehicle we worked on has a 9"x6" wiring harness in it. The process of reverse engineering that bad dog was unacceptable so we went to Ford. After shelling out big bux to Ford to say "we dont know where the problem is but we can keep working on it (for 65 per hour!)" We decided to mod the trans harness ourselves. You should have a multimeter available to you before performing this mod.

The E4OD in my opinion shifts like crap from the factory. Lockup engages in all gears somewhat randomly and really gives unpredicatable results in shift feel. There is a solution but it is not for everyone. Several companies make trans command adapters which work nicely if everything in the vehicle is electrically tight. If there are connection problems in the vehicle regulating lockup circuit the trans controllers will not work. So the only other option in curing this problem of shift feel revolving around intermitten lockup and wireing problems is to install a manual switch to bypass the computer controlls for this circuit. DO NOT LET THE WIFE OR KIDS OPERATE THIS VEHICLE WITHOUT THIS SWITCHED MARKED "KEEP THIS SWITCH OFF." If this switch is left on below the speed of 25 the vehicle will shake and you may leave parts of your trans or engine behind!! This Switch cannot be placed in the "on" position until the vehicle speed is above 35 for most effective shift feel and control. For guys that want that control over shift feel this really does work great and should improve mileage for those who experience lockup cycling. Lets begin.

Identify the Main electronic harness going to the trans. Above the trans connector about 4-5 inches locate the Purple wire with a white or Yellow stripe on it. This wire gets stained with oil so look closely. Simply cutting this wire will make the trans shift through all the gear ranges except for convertor lockup. The trans will at this point shift better then u have ever felt before because the gear ratios are all nicely matched by ford. Early lockup screws up this nice ratio thus this fix will eleminate this.

Now that the lockup wire is cut attatch 2 lengths of wire to the two wires that are now available at the trans (one length per each lead).
drill a small hole in the floorboard under the carpet to get the two wires up to your dash somewhere convient for a switch. At this point u need to do a test. Tie these two wires together. The trans should operate normally and lockup will come in as before you cut the wires. At this point all we created was a loop effectively lengthening the path of the convertor lock up circuit. Using your meter, and a second driver for the rig, get up to about 55 mph and hold steady. Set your meter to dc voltage on the 20 volt scale. Place your red lead to the two wires on your dash that are tied together and the black lead to the outer circle of your cigarette lighter (ground). At the speed of 55mph with the vehicle warm you should have a reading of about .5 to 3 volts. If you apply the brake and hold the speed at 55 you should see that voltage jump to 12-14 volts. If you let off the gas the voltage should be 12-14 volts. As you get back on the gas and return to 55 and level out you should see the voltage drop to .5-3.0 volts. With the vehicle in park the voltage should again be 12-14 volts. You will notice that when lockup engages the voltage drop occures and lockup takes place. We are going to manually drop this voltage by adding a ground which is effectively what the computer does to engage lockup. If these results are not typical of your vehicle STOP HERE!! Your harness may be different and this Mod will not apply to your vehicle.

Assuming your tests indicated the correct results and u have the two wires inside your vehicle, open up the two wires you tied together and place the red lead on one of those wires and the black lead to the cigarette lighter outer ring (ground). You should notice that one lead will produce 12-14 volts with engine on and in park and one wire of the two will produce .5-3 volts when measureing to ground. Note the High voltage lead. Take your switch and place the high voltage lead reading 12-14 volts on one of the switches poles and tighten it down. On the other side of the switch connect the remaining wire from the trans AND a jumper wire that is somewhere securely grounded to the chassis of the vehicle. This will in effect ground the second terminal to the chassis. The benefit of this arrangement will gives the driver total control of lockup. Notice that when the switch is open (off) the computer cannot engage lockup if it is undesireable to the driver and around town you will get nice crisp shifts that contain nice ratios as designed by ford. Once this switch is activated lockup will engange and HOLD for the duration the switch is on.

I recommend you only use the switch for highway use to increase economy. That is unless your like me, I like the ability to control shift feel and it doesnt bother me to toggle that switch off and on for stops. If your a control freak this is the nuts and works well. This mod was performed on a 91 Diesel ambulance converted to a service truck. As we have not tested it on all electrical configurations for each of the years we cannot assume that this mod will work in all applications. For those of you that it does work for, Enjoy....its a really nice feature that will payoff in economy. On the highway flip the switch and let her go!!! even if you let off the gas a little lockup wont fall out and then reengage like the factory controls. Once Boss Transmissions web site is back up we will provide schematics for those who would like to review the above procedure.

We make no claims about its intent or use. Perform at your own risk. Feel Free to Correct anything I have said here. Read this Thread thoughly incase others experience situations that are undesireable.

 

[rjjp]

umm, tech article, Mel?

 

[LCAM-01XA]

Lots of people do it to diesel trucks, but would a Gasser get any real benefit from this mod?

Someone on FTE recently did this to his 460-powered F250, says he's very happy with it. The E4OD's gear ratios didn't change from engine to engine like they do with the ZF5, if so what applies to one truck pretty much applies to all that have the same transmission, regardless of engine size or type.

That said, the E4OD will make lots of heat when you're running around with the converter unlocked, so make sure you have a good add-on trans cooler on top of the factory one in the rad.

 

[yARIC008]

Few things. One, leaving the switch on when you stop will not destroy transmission unless you are very unlucky. It will stall engine and make you feel like an idiot though. (only did that once)

Also, i discovered by accident that if it is locked up and you are in reverse it doesn't stall, it just makes an odd sound. Then when you shift into drive it'll stall out.

 

[LCAM-01XA]

umm, tech article, Mel?

Goofy actually quoted another tech article, it was posted on TDS or something - IMHO it's a bit confusing, and it also makes no mention of the 22k resistors that is sometimes needed to feed the PCM a dummy TCC signal, and also the brake-interlock relay that I think should be mandatory unless one thinks they ill never ever have to get on the brakes and stand on them for dear life while the converter is still locked...

Yaric, or depending on how high your idle speed is and what road surface you're on when you shift into drive with the converter locked the whole rear axle of the truck starts to hop and skip, it's an interesting experience for sure, lol

 

[Fozz]

Seeing as how my TC has given it's notice about quitting the organization, and based Jaki_IN's and Fozz's suggestions I went ahead and did the TC lockup mod today.

I am impressed at how the E4OD works without that lockup BS trying to lock and unlock the TC all the time. I have a switch under a BIG RED COVER saying T.C. LOCKUP and I made it VERY clear to the ONLY two people that will ever drive the thing without me....under NO circumstances, even if god himself says to, DO NOT TOUCH THAT SWITCH...purely because if they flick it and forget about it or flick it too early....bye bye transmission.

For those of you who don't know what a Torque Converter Lockup Modification is....I suggest you check it out and do it!

I will be doing the relay mod as RLDSL has...I touch the brakes and she unlocks....giving mye time to have that switch knocked off again.

Glad it worked out for you. The truck is much better driving around town with it unlocked, huh? I had wanted to put a Transgo Tugger kit in mine, but after doing the mod I'm totally satisfied with how it drives.