Still not getting TC lockup
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Axle/Gears: 9 bolt disc 3.27
Still not getting TC lockup
So I put a 700R4 where a 5 speed used to be (bought the car without a motor and trans then swapped in what I had). Both trannys are from an 1987 Iroc. I swapped in the TC brake switch, supplied it with power from the fuse block, then ran a jumper wire over to TC solenoid pigtail. When I swapped in the engine and tranny pair I also brought over the main engine wire harness and computer, so the other two wires from the TC solenoid pigtail are connected into that harness.
But as I drive the car I cannot perceive any torque converter lock up. At highway cruising speed I even tap the brake to unlock the TC to see if the rpm's will bump up and I don't see any change. When driving at 90kph (55mph) the tach reads about 1900rpm or just a touch higher, this is with 3.27 gears and stock tires, does this seem like high rpms to you at this speed? I ran a test light on the brake switch and it works just fine. So I'm wondering if I've overlooked something, or maybe something is wrong inside the trans?
But as I drive the car I cannot perceive any torque converter lock up. At highway cruising speed I even tap the brake to unlock the TC to see if the rpm's will bump up and I don't see any change. When driving at 90kph (55mph) the tach reads about 1900rpm or just a touch higher, this is with 3.27 gears and stock tires, does this seem like high rpms to you at this speed? I ran a test light on the brake switch and it works just fine. So I'm wondering if I've overlooked something, or maybe something is wrong inside the trans?
Last edited by Crusherfied; 07-24-2013 at 12:49 AM.
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Car: '86 Camaro, '94 Camaro, 3 others
Engine: LG4 ->L29, L32->LR4, L36, LG4, L31
Transmission: 700R-4, T5WC, 4L80E, SM465, 4L60E
Axle/Gears: 3.42, 3.23, WTB/WTT 2.93
Re: Still not getting TC lockup
1900 at 55 is about right for having OD but not having lockup.
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: Still not getting TC lockup
Was the lockup working correctly before the swap?
Have you checked for 12V into ( purple ) and out of ( tan / bk ) wires at the plug on trans?
The tan/bk wire is grounded at the ECM to turn on lockup.Run a temp wire inside the car from that wire to ground through a switch
and see if you can get the lockup to work .Engaging lockup 9 wire to ground ) with car in gear and stationary should make the engine stall.
If it doesn't you know you have internal problems (assuming it passes the above the electrical tests )
Last edited by vetteoz; 07-27-2013 at 02:29 AM.
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