700r tc lockup?

[87 Blue Beast]

we did a motor swap in my dads 86 camaro. ever since we did, the tc wont lock. it goes into od, but it wont lock, so its screams all the time while cruising. we put and older motor in it, so we elimitated all the wiring/vacuum lines. my question is, for an 86, what makes the converter lock? vacuum? computer? and what do we have to do to get it workin again? thanks

 

[cabledawg]

My 88 Burb has an electronic TC lockup. I wouldnt know about an 86. Both Jegs and Summit make electronic kits that can be controlled manually if you dont have an ECM in your car/truck. Just a switch for the dash and run the harness to the trans. Might wait to see if anyone here has ever used one.

 

[Thunder]

I dont know about the camaros but pre FI trucks have a vacuum switch on the firewall to control TC lockup. It needs a line ran to it from manifold vacuum. If you ditched all the vaccum lines. You better find one to hook up that switch or TC lock wont work unless you put a manual switch in
TC lockup is also controled by the VSS and the ECM. If you also elimiated them you will have to lock the TC manually

 

[87 Blue Beast]

so its most likely both vacuum and electronic..?

 

[Thunder]

Yes i think so IIRC It takes both high manifold vacuum and a speed of over 45 mph to allow the TC to lock.

 

[jonrpick]

we did a motor swap in my dads 86 camaro. ever since we did, the tc wont lock. it goes into od, but it wont lock, so its screams all the time while cruising. we put and older motor in it, so we elimitated all the wiring/vacuum lines. my question is, for an 86, what makes the converter lock? vacuum? computer? and what do we have to do to get it workin again? thanks

I'm not an expert on this by any means, and I want to know the answer too, but as an owner of an '86 K5 with a 700R4, I know this...Mine would UNlock when you hit the brake pedal. There *was* a small wiring harness running to the transmission just for that purpose. When I had an engine fire and most of the harness was destroyed, that section was one of a couple of things I couldn't relocate.

When I got ripped off and *had* to have my tranny rebuilt (idiots at Mr. Trans.) they put in some sort of manual lockup kit based on tranny pressure (I think). I know that now there's no vacuum or electronics going to the 700R4 at all, and that's how they set it up.

Hope that gives a little more insight.

 

[obijuan]

i bought this: http://www.700r4.com/tech/tcc/index.shtml relay type or brake switch

i got the brake switch:
http://bowtieoverdrives.com/catalog/catalog.php?Action=GETSUBCAT&CATID=OA1A2
it was very easy to install and took a couple of hours for me to figure it out, the guys on here helped a WHOLE lot. their directions have tiny pictures. it completly eliminates the stock lockup stuff because mine was MIA. i installed this and it locks up in OD and unlocks with the brake switch. a few other folks here have it and i personally have never had any problems.

 

[jonrpick]

i bought this: http://www.700r4.com/tech/tcc/index.shtml relay type or brake switch

i got the brake switch:
http://bowtieoverdrives.com/catalog/catalog.php?Action=GETSUBCAT&CATID=OA1A2
it was very easy to install and took a couple of hours for me to figure it out, the guys on here helped a WHOLE lot. their directions have tiny pictures. it completly eliminates the stock lockup stuff because mine was MIA. i installed this and it locks up in OD and unlocks with the brake switch. a few other folks here have it and i personally have never had any problems.

I need to get in there and see what they did. I'm not sure it's locking up as it's supposed to, and have no real way of checking. The tranny rebuild came at a time when everything was just so FUBAR'd that just getting it down the road was a challenge (it's worse now).

I wish I'd been using CK5 at that time. Instead I was depending on Usenet and while there was a lot of knowledge there, it was nowhere near as specialized as it is here.

 

[longbedder]

There were many different configurations of control for TC lockup, and even differences in which lockup would occur. Between the chassis (wiring) differences and the internal differences there were maybe 100 different combinations.

I wired mine so that it was purely manual - I installed a toggle switch in the dash, but also routed it through the brake light so that it would unlock when I hit the brakes. In this way I can lock it up in any gear whenever I feel like it, and also use it for engine braking on hills (6.2 deisel). It's a nice setup for a 4x4 play truck, but I'm not sure I'd like it in a Camaro.

 

[Gaffed]

If you don't fix the problem and continue to drive the car in OD it will overheat the tranny and die. My TCC switch was broken and the tranny never locked up and died.

 

[dyeager535]

A pre-FI ('86 and down) truck transmission relies solely on vacuum to lockup. VSS was NOT used as part of lockup.

For the price of the aftermarket TCC kits, I'd retrofit an early truck vacuum setup. It's simple, and pretty effective, as long as the engine makes any vacuum.