No WOT 2>3, out of ideas
07-07-2011, 04:36 PM
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No WOT 2>3, out of ideas Third trans so far in a year. Everything shifts fine until WOT. In WOT my 1>2 is perfect, yet I cant get a 2>3. Hits the Limiter every time.
Little background on the car. Heads and Cam LT1. MSII EFI controller running piggy back. Stock computer still running trans, all sensors are still running signals to the ECM. No DTC's are present.
4L60e Forged internals. Freshly rebuilt two days ago for the third time. Has an Edge 3600 hundred stall converter non-locking, all new consumables in the trans, all new electronics in the trans. Valve body looks good, all valves move freely. All clutch pack tolerances are in spec, all pressures are in spec. Also has a Transgo HD-2C kit.
Shift points are: 1>2 36mph at 5750, that shifts fine. 2>3 I set very low just to meet both parameters yet still cant get a shift. It is set at 50mph and 4500rpm.
When I get into WOT 1>2 is fine, 2>3 parameters are met yet it keeps pulling in second until about 75mph and 6300rpm and starts bouncing. Everything shifts fine until WOT. I keep burning up the 3/4 clutches. Driving on the highway is almost an impossibility, as soon as I go to pass it will start bouncing the limiter. I cant tell if it is slipping gear or just not shifting, but from the look at the burn steels and fried frictions I would assume it is slipping.
Any thoughts and ideas would be much appreciated. I have replaced TPS sensor, all shift and pressure solenoids. New VB separator plate. No VSS or MAF DTC's are present. Im starting to think the only way to fix it is a GPIO mshift board, or a $1.99 For Sale sign.
Thanks in advance for any ideas or help
Little background on the car. Heads and Cam LT1. MSII EFI controller running piggy back. Stock computer still running trans, all sensors are still running signals to the ECM. No DTC's are present.
4L60e Forged internals. Freshly rebuilt two days ago for the third time. Has an Edge 3600 hundred stall converter non-locking, all new consumables in the trans, all new electronics in the trans. Valve body looks good, all valves move freely. All clutch pack tolerances are in spec, all pressures are in spec. Also has a Transgo HD-2C kit.
Shift points are: 1>2 36mph at 5750, that shifts fine. 2>3 I set very low just to meet both parameters yet still cant get a shift. It is set at 50mph and 4500rpm.
When I get into WOT 1>2 is fine, 2>3 parameters are met yet it keeps pulling in second until about 75mph and 6300rpm and starts bouncing. Everything shifts fine until WOT. I keep burning up the 3/4 clutches. Driving on the highway is almost an impossibility, as soon as I go to pass it will start bouncing the limiter. I cant tell if it is slipping gear or just not shifting, but from the look at the burn steels and fried frictions I would assume it is slipping.
Any thoughts and ideas would be much appreciated. I have replaced TPS sensor, all shift and pressure solenoids. New VB separator plate. No VSS or MAF DTC's are present. Im starting to think the only way to fix it is a GPIO mshift board, or a $1.99 For Sale sign.
Thanks in advance for any ideas or help
07-07-2011, 11:46 PM
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07-08-2011, 10:27 AM
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Changed 3>2 shifts down same deal. Checked line pressure again today. Base line pressure in P, N, D are 85 psi at idle, R 130. Now while driving I'm not getting pressure above 120-150 psi. Got a serious pressure issue going on. New pump new boost valve. Wonder if I need to adjust the screw in the back of the new EPC solenoid. Could be a valve body issue. Who know. Any thoughts?
07-09-2011, 08:12 PM
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Turned out the pump slide wasn't clearanced. the top of the slide had witness marks on it from where it was rubbing the pump body. Rebuilt pump. Pressures still around the same at idle only this time they climb and dont bleed off at higher rpms.
Car doesnt chirp the tires in second, it hazes them now.
Car doesnt chirp the tires in second, it hazes them now.