2012 GMC Canyon Owner's Manual - Page 252

10-16 Vehicle Care After this is done: If not taken to the dealer, be sure to follow all the instructions here, or a false reading on the dipstick could result. Notice: Too much or too little fluid can damage the transmission. Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if checking the transmission fluid. Check the fluid level only when the engine is off, the vehicle is parked on a level place and the transmission is cool enough to touch the transmission case. How to Add Fluid Here is how to add fluid. Refer to the Maintenance Schedule to determine what kind of fluid to use. See Recommended Fluids and Lubricants on page 11‑11. 1. Remove the fill plug. 2. Add fluid at the fill plug hole. Add only enough fluid to bring the fluid level up to the bottom of the fill plug hole. 1. Remove the fill plug. 2. Check that the lubricant level is up to the bottom of the fill plug hole. 3. If the fluid level is good, install the plug and be sure it is fully seated. If the fluid level is low, add more fluid as described in the next steps. 3. Install the fill plug. Be sure the plug is fully seated.