The rubber or plastic seals become brittle with age and crack, or simply wear out.
The 1997 Pontiac Sun fire axle seal can leak because of age. A bad wheel bearing is the most common cause for an axle seal to leak.
Transmission fluid leak can be caused by couple of things. Most common being an worn out or broken seal. The transmission seals on most cars are made from rubber or metal. Seal is exposed to extreme temperature for years and the parts moving around them will eventually cause seals to fail resulting fluid leak. Faulty installation of a seal can also cause a leak. The another thing that can cause a leak is, if transmission case or pan is damaged due to low ground clearance.
The cam sensor seal can cause a leak if not installed correctly.
You could strip the threads and cause a leak very easily.
Damaged or manufacturing defect in the seal before installation, improper installation, deterioration of the seal over time.
check front seal it could be blown out
If the leak is by the passenger floor-- could be the heater core check to see if this leak is engine coolant or just water. Could be a leaking windshield seal could be a door seal could be evaporator line is plugged
Could be a bad seal, which will eventually cause your turbo to go out.
The intake manifold or the timing cover seal.
Depends on where the leak is falling from it could be the rear main seal leak, transmission back part connected to the transfer case, or a front main seal leak, the transmission part connected to the engine block also a possiblity is the shifter gear box if you have a standard, which also be in the front near the front main seal.
A poor seal or a split.
can you give installation of mechanical seal details