Veins and Venules: Veins are the large return vessels of the body and act as the blood return counterparts of arteries. Because the arteries, arterioles, and capillaries absorb most of the force of the heartâs contractions, veins and venules are subjected to very low blood pressures.
Wondering when to change your automatic transmission fluid (ATF)? Most manufacturers recommend replacing transmission fluid every 30,000 to 60,000 miles. If you tow, or do mostly city driving with constant changes of gears, it may be wise to change your ATF even more often. Here's why. Your automatic transmission has a lot of moving parts.
By Tom Burden, Last updated: 10/10/2016. Most sterndrive and outboard manufacturers advise you to change the gearcase oil in your lower unit every 100 hours or once a year (whichever comes first). Clean oil is critical for protecting the heavily loaded gears in your lower unit and preventing expensive damage.