Trans failsafe program
- Thread starter frosty123
- Start date
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Datatek
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They are well known for the GM gearbox failing, they generally last about 80K miles. Sounds like you are in for an overhaul of the box with a Sonnax valve block to replace the original made of cheese.
So changing the solenoid won't fix it
Datatek
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No Idea really, but even if it does it's likely o be a short term fix. What mileage is the car on?
167000
brianp38dse
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Have you checked the battery, if the volts are low it will throw all sorts of faults up on the dash just for fun, if lower than 12.4v things are not good.
brianp38dse
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11.36 is a buggered battery treat it to a new one an mf31 120ah 1000cca from battery megastore, its the biggest that will fit and only just by a few mm`s and put the new one on charge over night before you fit it as it many have sat on a shelf for awhile.
Bemble
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The GM 5L40-E transmission has five solenoids :
My guess would be that it’s probably the main pressure control solenoid
If you temporarily disconnect the 20-pin plug at the back of the transmission, and measure the resistance between pins 8 & 13, you should get a reading between 3.5 and 4.6Ω
Phil
- Pressure control solenoid
- TCC PWM solenoid
- 1-2 shift solenoid “A”
- 2-3 shift solenoid “B”
- 4-5 shift solenoid “C”
My guess would be that it’s probably the main pressure control solenoid
If you temporarily disconnect the 20-pin plug at the back of the transmission, and measure the resistance between pins 8 & 13, you should get a reading between 3.5 and 4.6Ω
Phil
Datatek
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13.84 is too low when running, if it's the same with a new battery you need to check the earth connection from engine to chassis and battery connections.
I had a 52 reg from new, the gearbox failed at about the same mileage despite having had the oil changed. I got the box rebuilt, cost about £3k, that lasted a yer and the torque converter failed in a snow-clad Belgium in the middle of winter. Got it trailered back to England and the gearbox repair man done it under warranty even though it was 3 days out of warranty. It lasted a bit longer and kept giving faults until I got rid of it in about 2016. It had done well ove 250,000 miles, but cost a bloody fortune in repairs.
