Psych0matt Posted April 27, 2012 Report Share Posted April 27, 2012 So I realized tonight that any time I'm on the freeway just cruising ~70mph the monte decides to drop down into third gear and cruise along at 3500rpm. Realistically it should drop into OD and be around 26-2700rpm, correct? Why would it do this, and what can I do to fix! I got up to about 80mph, threw it into neutral, turned the car off and then restarted, put back into gear, and would cruise for a few in OD, and then downshift... I've noticed the downshift before, but never realized it was staying in that gear until tonight Quote Link to comment Share on other sites More sharing options...
Addicted to eaton Posted April 27, 2012 Report Share Posted April 27, 2012 My 95 GP did this.. I was told everywhere tq clutch was going out. Quote Link to comment Share on other sites More sharing options...
jman093 Posted April 27, 2012 Report Share Posted April 27, 2012 Is the check engine light on? Depending on the condition, if it detects the trans slipping it often times will lock out 4th and TCC lock-up. When this happened on my sister's 96 Z34, it only locked out TCC lock-up, but the pcm definitely can lock out 4th as well depending what exactly it sees. Obviously any detected slipping by the trans causes the pcm sets the check engine light. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 27, 2012 Report Share Posted April 27, 2012 95 LQ1 PCM will lock out 4th gear and/or TCC based on trans temps and TCC slippage. neither are good signs. i've also had an odd instance where the DTC for the shifter position switch got triggered when i manually downshifted into 3rd. after moving the shifter back into 4th, still only had 3rd and no lockup. that one only happened once or twice though. Dan (galaxie500XL) did have a rather informative thread that explained another cause.... seems the TCC apply piston and it's bore/seal can become quite worn. to the point of where it works fine when the trans is relatively cool, then as it heats up, the TCC starts slipping due to the piston/seal allowing too much internal fluid leakage, which causes the PCM to disable the TCC. might want to search for the thread and see what similarities you can find. Quote Link to comment Share on other sites More sharing options...
Psych0matt Posted April 27, 2012 Author Report Share Posted April 27, 2012 I have had no check engine light this thread? http://www.w-body.com/showthread.php/42020-95-DOHC-Cutlass-P0740-no-overdrive-no-TCC-when-hot reading now Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 27, 2012 Report Share Posted April 27, 2012 yeah, that's the thread. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 27, 2012 Report Share Posted April 27, 2012 I advocate adding a transmission cooler. it could and has helped...... but yeah, sounds like the transmission is starting to wear out. Quote Link to comment Share on other sites More sharing options...
Psych0matt Posted April 27, 2012 Author Report Share Posted April 27, 2012 hmmm, I may be a bit more serious about wanting to sell the thing now... Runs great, aside from needing plug wires, maybe a new water pump (low coolant light comes on at times, but never gets hot or overheats) Quote Link to comment Share on other sites More sharing options...
Night Fury Posted April 27, 2012 Report Share Posted April 27, 2012 Quote Link to comment Share on other sites More sharing options...
alec_b Posted April 27, 2012 Report Share Posted April 27, 2012 Had this issue with my '95 Grand Prix. It was the TCC PWM solenoid going bad. Basically, there's two parts to the TCC circuit. One solenoid to control lockup apply and another to control lockup "feel". All I had to do was clip the wire to the "feel" side of the circuit, the PWM solenoid, and it was fine. Granted, lockup feel was MARGINALLY increased, but personally I liked it better. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 27, 2012 Report Share Posted April 27, 2012 I agree. I always cut that wire, too. Quote Link to comment Share on other sites More sharing options...
Psych0matt Posted April 27, 2012 Author Report Share Posted April 27, 2012 where is this wire? Quote Link to comment Share on other sites More sharing options...
urbex Posted April 27, 2012 Report Share Posted April 27, 2012 I told you not to buy this car.... ...oh wait.... Quote Link to comment Share on other sites More sharing options...
AL Posted April 27, 2012 Report Share Posted April 27, 2012 Shouldve bought my Regal Quote Link to comment Share on other sites More sharing options...
Addicted to eaton Posted April 27, 2012 Report Share Posted April 27, 2012 yeah! IT doesnt have a tq clutch to worry about locking up! such a better deal Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted April 27, 2012 Report Share Posted April 27, 2012 where is this wire? on the trans connector plug. brown wire. position "C". there will be another brown wire in position "E", do NOT cut that one. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted April 27, 2012 Report Share Posted April 27, 2012 Is this where I post pics of my knob????? Quote Link to comment Share on other sites More sharing options...
Psych0matt Posted April 28, 2012 Author Report Share Posted April 28, 2012 well, all the way home cruising at 70mph/2400rpm and it never dropped into third. it's also cold out. Coincidence? Maybe I'll try a tranny cooler... Quote Link to comment Share on other sites More sharing options...
AL Posted April 28, 2012 Report Share Posted April 28, 2012 yeah! IT doesnt have a tq clutch to worry about locking up! such a better deal Comes with an 18k mile trans too Quote Link to comment Share on other sites More sharing options...
Galaxie500XL Posted May 1, 2012 Report Share Posted May 1, 2012 That MAY fix the problem...ultimately, the solution for my '95 was a transmission rebuild....after which the transmission STILL did this, only at a higher temperature (205 degrees). The trans shop found another 4T60E, rebuilt it, and installed it in my car, for free. That finally fixed the problem. Had this issue with my '95 Grand Prix. It was the TCC PWM solenoid going bad. Basically, there's two parts to the TCC circuit. One solenoid to control lockup apply and another to control lockup "feel". All I had to do was clip the wire to the "feel" side of the circuit, the PWM solenoid, and it was fine. Granted, lockup feel was MARGINALLY increased, but personally I liked it better. Quote Link to comment Share on other sites More sharing options...
Galaxie500XL Posted May 1, 2012 Report Share Posted May 1, 2012 I added the transmission cooler to mine, which lowered the temperature, and meant I could drive an average of about 15 miles farther before the ECM locked out the TCC.... well, all the way home cruising at 70mph/2400rpm and it never dropped into third. it's also cold out. Coincidence? Maybe I'll try a tranny cooler... Quote Link to comment Share on other sites More sharing options...
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