2009 Chevrolet Colorado Owner's Manual - Page 274

Manual Transmission Fluid When to Check A good time to check the manual transmission fluid is when the engine oil is changed. However, the fluid in the manual transmission does not require changing. After this is done: How to Check Because this operation can be a little difficult, you may choose to have this done at your GM dealer/retailer service department. If doing it yourself, be sure to follow all the instructions here, or there could be a false reading. Notice: Too much or too little fluid can damage your transmission. Too little fluid could cause the transmission to overheat. Be sure to get an accurate reading if you check your 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. 1. Remove the filler plug. 2. Check that the lubricant level is up to the bottom of the filler 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. 5-24