Shortly after purchasing a 2007 new body Silverado 4X4 to pull a 25' Fifth Wheel Trailer, I noticed the Trans Temp was running approx 220-230 degrees. I installed an after market high-capacity transmission oil cooler core with a Tornado 10 in. Electric fan, Afterward the transmission temp rarely exceeded 185 degrees. That was 3 years ago.
This week, while traveling (65 MPH) the RPM suddenly revved to approx 4K. I let off the accelerator and slowed, then began to increase speed, when the same condition occurred.
I put the transmission in neutral and slowed to a stop on a freeway off-ramp. Shut off the engine and exited the truck.
When I looked at the front end of the vehicle, I saw transmission fluid dripping on the ground from under the front bumper. Opening the hood I could see one of the hoses had come free and was lying on the wind screen below the radiator. Called for a tow truck and was towed on a flat-bed-tow truck to a small town repair shop.
The tech repaired the cooler hose and added 5 qts of transmission fluid.
On the test drive, the transmission will shift into Rev-Neut-Drive-1st-2nd without issue but at the 3rd gear shift point, the engine only races.
I am now waiting to have the Silverado towed to a Chevy dealer for what may be an expensive repair. With only 16,000 miles I fear I may have destroyed my trans. Comments?
Unfortunately I feel that the problem will be as you say "an expensive repair" total loss of drive like that indicates a failure of either a loss of hydraulic pressure or a clutch / band failure as you have drive in all other gears the pump, torque converter and governor appear to be working as they should, they should do a line pressure test first as this will prove shift pressure and a scan to identify any electrical problems, but with the loss of fluid the signs are not good, but we live in hope, get the diagnosis done and hopefully it is not as serious as first thought.