Jim Grant's Tech Tips
'97 GMC C1500, Load Testing the Engine
a problem with my 97 GM C1500, my mechanic put the auto transmission
in gear and applied some throttle while holding on the brakes. This helped
him to diagnose a problem that was only occurring under load. Will this
technique harm the transmission or anything else in the drivetrain? If
so, would the damage show immediately or cause something like a slippage
that wears out over time?
approach youre describing is commonly used in diagnosing a load
related driveability problem. If used correctly this procedure will not
damage a transmission. If performed incorrectly thats a different
story. I can guess by your question that youre now having transmission
problems and want to know if the tech working on your vehicle is responsible.
If the tech sat there with his/her foot hard on the gas pedal with the
transmission in gear for an extended period of time it will cause damage.
But, light to medium throttle applications for short intervals is not
damaging. After all how do you think a transmission shop checks torque
converters and transmissions for problems?