Both.
A vehicle propelled down the road is typically powered by an engine, which can be internal combustion (using gasoline or diesel) or electric (using batteries). The engine generates power that drives the wheels through a transmission system. Additionally, vehicles can be propelled by alternative energy sources, such as hydrogen fuel cells or hybrid systems that combine different power sources. Overall, the propulsion mechanism allows the vehicle to move efficiently along roadways.
No,it does not do any damage to the engine or the drive-train of the vehicle with an automatic transmission
The transmission is located in close proximity to the engine, usually (in Hyundai's) transversely mounted directly under and behind the engine (behind the engine in terms of: following from the front of the vehicle towards the rear of the vehicle). If you follow the transmission fluid dipstick housing (shaft) down - that transmission fluid dipstick housing will end directly into the upper-most part of the transmission housing.
The year, make, model, transmission and engine info would help but it is probably the transmission down shifting if the vehicle is an automatic.
The engine's crankshaft converts the up-and-down motion of the pistons into rotary motion. This rotary motion is then transmitted to the transmission and wheels to propel the vehicle forward.
If the vehicle is an automatic transmission then you will find a DIPSTICK inserted in a filler tube that goes down to the transmission . Locate the tranny in the engine bay and you will find it. It IS IN THE ENGINE COMPARTMENT and is very similar to the OIL dipstick but it IS LONGER. If the vehicle has a MANUAL (w/clutch) tranny then the only way to check it is from underneath the vehicle by unscrewing a drain or drain/fill plug. This is always on the SIDE of the transmission and looks like a HEX bolt.
Look in the engine compartment very carefully for the dipstick. On an engine mounted longitudinally, as in a RWD vehicle, it will be located near the firewall. On an engine mounted traversely as in a FWD vehicle it will be normally located on the drivers side down low in near the transmission, but it may be on the passenger side. On some newer vehicles, especially GM, there will be no dipstick as the transmission is a sealed unit with no way for the owner to check the fluid level.
When you slow down in a vehicle without stepping on the brakes, the RPMs typically increase because the engine needs to work harder to maintain a consistent speed. This is due to the transmission downshifting to a lower gear to match the reduced speed of the vehicle, increasing the engine speed.
As you are looking into the engine bay from the front the transmission is on the back side of the engine about half way down.
When a vehicle has no engine brake, it means that the vehicle does not have a system that helps slow it down by using the engine's resistance to assist with braking.
The location of the dipstick for checking the transmission fluid varies from vehicle to vehicle. For vehicles with engines mounted in line with the drive shaft and transmission (pickup trucks, Ford Mustang, Chevy Camaro, ect.) the dipstick for checking the transmission fluid is usually located near the back end of the engine block, sometimes lower down along the side of the engine. It often looks like the dipstick that used to check the oil. Remember to check transmission fluid the engine should be running when your doing it. Also its important that you don't over fill.
Yes coasting downhill will save you fuel. However do not do this with a vehicle equipped with automatic transmission. You will damage the automatic transmission by coasting. You can do this with a manual transmission but do not shut the engine off. This would cause you to loose power steering and power brakes.