I have a 2001 Pontiac grand prix GT with 119500 miles. Since last week my speedometer is acting crazy and the transmission won't shift past 1st gear. I suppose the Vehicle speed sensors are gone bad, my car has two speed sensors, transmission input speed sensor is inside the transmission, side cover has to come off to change the $20 sensor, while there I can ask the mechanic to change all the solenoids but is it better to rebuild the transmission rather than just changing all the transmission sensors.
Rebuild 4t65e or change all the transmission sensors?
- Thread starter easym
- Start date
Road speed is calculated off the Output Speed Sensor, I would start there!! Use a OE Delco Sensor.
Well this boils down to how well has the transmission been maintained.
If the transmission was regularly serviced and overall the transmission is still healthy then I would just go for the sensor. If the transmission was not regularly serviced and the fluid is very dark and there is a lot of clutch material or metal in the pan then rebuild it if you intend to keep it long term.
There is zero point in rebuilding a healthy transmission.
Use only AC Delco/GM Genuine sensors.
If the transmission was regularly serviced and overall the transmission is still healthy then I would just go for the sensor. If the transmission was not regularly serviced and the fluid is very dark and there is a lot of clutch material or metal in the pan then rebuild it if you intend to keep it long term.
There is zero point in rebuilding a healthy transmission.
Use only AC Delco/GM Genuine sensors.
Did you check for codes? I had a transmission output speed sensor go bad before and I got a code. No dash light is not an excise for not checking for codes. On one car I used to have transmission codes didn't make the check engine light light up. You would need to use a scanner capable of reading transmission codes. As to how I know that last part, it was a 2000 Dodge Dakota with a bad output speed sensor that was bad. No CEL, and my code reader showed no codes, but using the Chrysler turning the key on and off 3 times and looking for codes at the odometer provided the code.
My point being don't assume. If you think you have solenoid issues, check the resistance on them and independently energize them..
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There is no codes but my speedometer fluctuates wildly and it doesnt accelerate.
What code reader did you use?
I used Torque pro.
Are you sure that can read transmission codes for your application? Know anyone with a Tech2?
No I have to go to a transmission shop to check Tech2.
Even the cheapest scan tool should be able to show the vehicle speed. Check that.