There's rarely a dipstick for the manual transmission, so when you're doing other lube work, remove the fill plug and see if the level is even with the bottom of the plug hole. Drain and refill the transmission at least once every two years, taking care to use only the specified lubricant. Some gear oils will not adequately protect some of the metals of a transmission, or may be so thick they affect shift quality.

Many modern transmissions specify the use of multiviscosity engine oil in the transmission. That's right, engine oil. We did a doubletake the first time we saw that one ourselves. If that's the spec for your tranny, fine just be sure to use the proper viscosity. Automatic transmission fluid is often recommended for year-round use in some manual transmissions. However, it may not match the protection offered by gear lube for hard use in hot weather, so if ATF is a winter-only recommendation, change to the specified gear oil in the spring.

Although most automatics can use Dexron II or a name-brand universal transmission fluid that meets Dexron II and Ford Mercon standards, older Ford automatics and some imports require a fluid that meets Type F standards. Use the right fluid, or transmission shift quality will suffer.

Rear axles with limited-slip differentials use a lubricant with friction modifier to prevent chattering around slow corners. Be sure to check the label on the container to see if you've got the right stuff.