* Worn-out transmission pan gasket: This is the most frequent cause. Over time, the gasket hardens, cracks, or shrinks, allowing transmission fluid to seep out.
* Loose or damaged drain plug: A simple, but often overlooked, cause. A stripped or loose drain plug can lead to leakage.
* Cracked or damaged transmission case: This is a more serious problem, usually caused by impact or corrosion. It requires a more extensive repair.
* Failing transmission seals: Various seals within the transmission itself can wear out and leak. These include input shaft seals, output shaft seals, and others. This is a more involved repair.
* Damaged transmission cooler lines: The lines connecting the transmission to the radiator can develop leaks due to rust, corrosion, or damage.
* Overfilled transmission: While less common as a cause of a *leak*, an overfilled transmission can cause fluid to overflow and leak out.
* Improper installation of parts: If the transmission has recently been serviced or repaired, improper installation of parts could be to blame.
Diagnosing the leak:
To pinpoint the source of the leak, you'll need to:
1. Locate the leak: Carefully inspect the transmission and surrounding areas for fluid. Look under the vehicle, paying close attention to the pan, cooler lines, and shaft areas.
2. Clean the area: Thoroughly clean the transmission area to remove any existing fluid. This will help you identify the source of the fresh leak.
3. Observe the leak: After cleaning, drive the vehicle and observe where the leak reappears.
4. Check the fluid level: Check the transmission fluid level to rule out overfilling.
If you're not comfortable performing this diagnosis yourself, it's best to take your Blazer to a qualified mechanic. They have the tools and expertise to accurately identify the problem and perform the necessary repairs.
