Churchkey

Scored a 4L60 (no "E") & need TCC lock up in 4th gear. Have to do it internally the trans has zero external pressure ports.

Found a GM 24502513 kit @ Jegs

http://www.gmperformancemotor.com/parts/24502513.html

Wiring will be 12V Ign feed through a 4 pin brake light switch, possible on/off toggle switch & a electric vacuum switch later if need be.

Thoughts?

Thanks

WVZR-1

Is it an OE 4L60 or a reman from someone? If you have any FSM that includes the 700R4/4L60 if you look in the 4L60 diagnostics you'll see several different schematics for valve body wiring. I'd think you ID yours and maybe "Arbee can provide some ideas as to what you've got and maybe change. Is there a trans ID on the pan rail of the case? 3/4 connector square or a later '92+ 5-round?

What year FSM do you have?

The package you linked to looks to be a lot of money for a simple switch and a connector. It appears the kit includes both style connectors, thru '91 3/4 square and the later '92-'93 5-round.

TCC wiring:

http://www.rowand.net/Shop/Tech/LockupTCCWiring.htm


switches etc at the very bottom of this link. Most around here don't do 4L60 anymore but -e transmissions. nearly all of these switch #'s look familiar.

http://www.rowand.net/Shop/Tech/Auto...issionSwap.htm

383vett

Whether you have the round or square connector, what you want to do is ground the tcc solenoid wire through a switch. I use my old 4+3 switch on the console and have on demand lockup. The lockup solenoid is provided with 12 volts when the ignition is on (I believe). You need to ground the other end.

arbee

I also have used a relay with a holding contact powered through the brake switch. When stepping on the brake, it drops out the TCC.

Churchkey

Thanks for the reply's guys.

Trans is a rebuilt 92 unit from a 92 3/4 ton GMC van it is slated for my 57 Chevy build.

Agree the linked kit is pricy but I could not comprehend the normally closed pressure switch that comes with the kit, the stock pressure switch I have is normally closed. Unlike the 700R4 trans with numerous pressure switches the 4L60 has 1 (one) = confusion on my part.

Found a Hot Rod Mag article from 2001 on line = its really simple & no expensive kit to buy.

Here's the scoop.

Remove the normally closed pressure switch next to the servo @ the front of the case.

Install a normally open / pressure closed switch GM part # 8627332 or
8642473 in its place

Connect the black ground wire from the lock up solenoid to the new pressure switch.

Connect the other solenoid wire to a 12v supply from a fused 4 pin brake pedal switch, dash switch, elec /vac switch etc.

TCC lock up will occur in 4th gear.

My dealer will have the switch Monday.

383vett

Hope it works for you. Does this mean whenever the tranny is in 4th gear, you have tcc lockup? If so, I would think this would lug the motor in certain situations after the 3-4 shift. With my console switch, I used the lockup as a 5th gear on the freeway after 4th was done pulling the car.

Churchkey

Yep 4th = TCC lockup.

I considered eliminating the automatic TCC lockup function completely as you have done for manual control but have yet to find a road in E TN that is straight & flat enough to see the horizon. I'll install a
elect / vacuum switch in the 12V feed = TCC lockup @ high engine vacuum during cruise. May also toggle switch the 12V feed to kill the lock up if necessary.

Thanks