Part 5 of 5 – Fluid Leaks
Part 5 – Manual Transmission and Differential
Older manual transmissions use a heavy thick oil. Shifter levers on the side of the transmission seem to never leak. However the rear tail stock where the drive shaft goes into it may leak. This type of leak will be near the center of the rear of the transmission. The front of the transmission is sealed. A leak in this area would cause concern as to how the car shifts gear. A bad bearing or input shaft may cause a leak, which should be looked at. In normal conditions a manual transmission should never leak. Any leaks with a manual transmission should be inspected. The most common leak is where the speedometer drive gear goes into the side of the transmission. This type of leak would be off center to the transmission.
The differential on these old cars leak a heavy dark thick oil. It also smells very bad! Anything bigger than 1 inch in diameter should be a concern. You may see this type of oil in the center of the rear axle or at either end of the wheels.