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.
If you happen to drive in severe conditions (hot climate or lots of stop and go driving) or tow heavy loads, you should change the fluid more often, perhaps every 15,000 miles. Doing so ensures that your transmission is only working with the best fluid.