Volvo S60 transmission problems

I just had my transmission replaced on a 2004 S60 Volvo. There were 65,000 miles on the car, 15,00 out of warranty. It was $5,000 to replace the transmission by a ‘certified’ Volvo mechanic. I have been using this mechanic for years. Since the replacement of the transmission the cruise control does not function properly, the gas gauge is either off or the car is consuming fuel, and the instantanteous mileage indicator constantly and consistently jumps from sequences like 3, 17, 24, 6, 48, 82, 99.9, 7, 72, etc. The mechanic claims he can find nothing wrong, including any computer error codes. He then told me to sell the car if I’m not happy. Sell a 2004 Volvo that I just put a $5000 transmission in? I have made an appt. with a Volvo dealer, but does anyone have any ideas? Thank you.

I don’t know what kind of sensor it uses to pick up the car’s speed, but I suspect it is on the transmission and it is now having problems. From all you said, I would suggest there may be a grounding problem to the transmission.

You can try a cheap fix by running a cable from a known ground to the transmission case, or see if there is a current ground wire to it and make sure it is intact and both ends are tight and clean. You might even use a meter on the transmission case to the ground and start pulling twisting jiggling everything it sight to see if one of them reacts.

You may want to check the wires or cable to the sensor on the transmission to see if you can fix it there.

Thank you for your response.