Early automatic transmissions had just two speeds.
Today's modern transmissions have up to eight speeds and now match the fuel economy and performance of a manual transmission.
Through the changes that have taken place over the years, one thing remains true - taking care of your transmission extends the years and miles it will give you.
Good driving habits, routine maintenance and service, and other important habits will keep your transmission working at its optimal performance for as long as possible.
For the purpose of this article, most of the information discussed is related to automatic transmissions unless otherwise noted.
Getting power from the engine to the wheels of an automobile has provided a seemingly endless challenge for rear-wheel-drive, front-wheel-drive, 4-wheel-drive, front-engine, rear-engine, and mid-engine cars, longitudinal, transverse, vertical, slant, and flat engines, plus an amazing array of hardware in between.
At the heart and center of the drivetrain is (and always has been) the transmission.
Because gasoline engines develop their torque over a very narrow speed range, several gears are needed to reach useful road speeds.
(Steam engines and electric motors can be used in cars with no transmissions.
) The modern transmission was introduced by a pair of Frenchmen -- Louis-Rene Panhard and Emile Levassor -- in 1894.
Rene Panhard and Emile Levassor were partners in a woodworking machinery business, when they decided to become car manufacturers.
They built their first car in 1890 using a Daimler engine.
The engineers had invited the press to a demonstration of "the most revolutionary advancement to date in the brief history of the motor car industry.
" Unfortunately, the engine in their demo vehicle died, and they were reduced to giving an oral presentation on multi-geared transmission theory to the press who were less than enthralled.
According to one website on automobile history, "Cars of the time transmitted engine power to the wheels in a simple fashion that was easy for non-engineers to visualize.
The engine drove a set of bevel reduction gears that drove a shaft and pulley.
Leather belts extended between the pulley and geared wheels on an axle.
One wheel, the small one, got the car going by meshing with a ring gear on one of the driving wheels.
The big wheel then took over to get the car to hustle along at a top speed of 20 mph.
If the car encountered a hill that it did not have the power to climb, the driver would come to a dead stop so he could engage the small wheel.
" The basic parts of a modern transmission are the bell housing (the cone shaped metal case that you can see when you peek underneath your car.
If you have a front-wheel-drive car it's stuck on the side of the engine under the hood.
If your car is rear-wheel-drive, the tranmission will be mounted underneath the car behind the engine), the gears, transmission fluid (which is very important to an automatic transmission.
All of the magic happens in the fluid.
Most cars come with red transmission fluid, good to know if you are looking for a leak), and the filter.
There are different types of transmissions, as most people know.
Manual transmissions require the driver to use a stick to shift between the car's gears, while the car does this on its own with an automatic transmission.
There are advantages to driving either type.
As explained by eHow, "many more cars come with automatic transmission over manual.
Manual stick shifts are found in very few models outside of compact or sports cars and a few pickup trucks.
Furthermore, cars with automatic transmissions are simpler to operate, as the driver doesn't have to worry about operating the clutch pedal and switching gears every 2500 rpm.
They also explain that "An automatic can be a good choice for young drivers learning to operate a vehicle.
However, the added control of a stick shift can be an advantage in areas with sharp turns and inclement weather.
" There are other pros and cons too like fuel economy, although recent trends have the playing field more even.
Historically, cars with manual transmissions tended to get better gas mileage than those with automatic transmissions.
Tests by consumer organizations indicate that manual transmissions can result in two to five more miles per gallon.
There are multiple reasons for this, but it is generally because an automatic transmission is more complex and requires more energy to automatically shift gears as opposed to when the driver controls the gear shift.
Cost is another different between manual and automatic transmissions.
Cars with automatic transmissions often cost more than ones with manual transmissions (an average of around $700 more.
) This can be seen as a small percentage for a vehicle costing more than $20,000.
However, the lower gas mileage will also increase the cost of operating an automatic transmission.
Performance and maintenance also has it's advantages as explained on their website.
For example, cars with automatic transmissions generally require more maintenance than their manual counterparts.
Due to the complexity of an automatic, there is a greater risk of parts within the transmission breaking down.
According to former Indy car mechanic Dave Bowman, regular fluid and filter changes are the key to keeping your automatic transmission trouble free.
Bowman says that, ideally, the fluid and filter in the transmission should be changed every two years or 24,000 miles, particularly if the vehicle is over five years old.
He points out, however, that many newer cars and trucks need scheduled service less often and some new vehicles have transmissions that need no service for the life of the car.
He advises that all car owners check their owner's manual to see what the service interval on their vehicle's transmission is.
According to Peter D.
du Pre, "Bowman and other industry experts also warn that by-the-book service may not be adequate if your vehicle is driven hard, tows a trailer, goes off-road, or carries a camper.
Under these conditions, changing the fluid and filter every 12 months or 12,000 miles is important because dirt and moisture buildup in the fluid can cause internal damage.
Heat buildup can also be a problem.
The harder the transmission works, the hotter the fluid gets.
" According to Ron Sessions, author of the Turbo Hydra-Matic 350 Handbook (HP Books), the ideal operating temperature for transmission fluid is between 175 and 225 degrees Fahrenheit.
"Anything other than light-duty use will raise fluid temperature beyond this.
Next to regular fluid and filter changes, installation of an automatic transmission fluid cooler can go a long way towards increasing transmission life, particularly if you tow a trailer.
" The transmission oil is critical for lubricating the transmission and reducing friction.
When the fluid breaks down and loses its viscosity, it no longer effectively lubricates the transmission.
This causes premature and excessive wear and results in transmission failure.
After 30,000 miles, transmission fluid begins to show its age as it turns brown in color and oxidizes due to the combination of time and heat.
Deposits begin to form around the transmission's many moving parts, resulting in valves that stick and gears that slip or are sluggish and chatter as they shift.
Transmission flushes have been at the center of debate for a long time.
It is important to find an auto repair shop that will properly flush your transmission and service it completely.
Rather than just removing the fluid found in the bottom of the pan, the entire transmission should be cleaned and replenished with the use of special equipment.
The transmission and its torque converter need all of their old contaminated fluid removed while new fluid and premium conditioners are added.
This will make one of the hardest working parts of your vehicle shift smoothly and effortlessly for many more miles to come.
Checks and changes of fluid are an important part of transmission care, but so are driving habits.
According to Bowman, one common practice that really hurts the transmission is shifting from drive to reverse while the vehicle is still moving.
Always make sure your foot is on the brake and the vehicle is stopped before shifting into reverse.
Manual downshifting into low range can also be damaging.
Many vehicles aren't designed for low range driving except under certain conditions.
Check your owner's manual.
Another habit that shortens transmission life is to park without using the parking brake.
This is an especially bad practice when the car is parked on a slope since it puts all the vehicle's weight on a tiny metal catch inside the transmission.
Other tips from auto repair shops all over the country include avoiding sudden stops and sudden acceleration.
When you stop your car, no gear should be shifted.
Frequent shifting might cause transmission problems, which would require you to go for transmission repair.
Give time for your engine to get warmed before driving because the fluid needs to be warm enough to help the transmission work properly.
Always go for your brakes instead of your gear shift when you want to stop your car.
Drive in the gear most appropriate for your speed - simply listening to your car can tell you where it is most comfortable.
Noticeable transmission problems may include either it won't go, or it won't go easily.
Your fluid level could be incorrect, your transmission could be leaking, the filter could be clogged, or you may need a rebuild.
The important thing is checking any other possible causes to your problem before you take the transmission apart, which is very expensive.
If you haven't replaced your filter yet, do it! This fixes a nice percentage of transmission problems.
Otherwise, a rebuild can cost quite a hefty amount of money.
If and when the time come that you need to have your transmission serviced, follow these beneficial tips for choosing a trusted repair shop: First, be cautious of choosing a shop that offers cut-rate specials.
This could also mean cut-rate service.
Second, check a shop's credentials before you allow them to tow your car and have to deal with that part of the issue.
Make sure they have some type of a clear guarantee before the hook you up.
Third, check for certifications.
Good shops always have their training certification and memberships on the wall.
These should be from ASE (Institute for Automotive Service Excellence), ATRA (Automatic Transmission Rebuilders Association) or other nationally recognized trade organization.
If they are not posted, you could ask to see the certificates.
Fourth, don't be mislead by the warranty claims.
A good shop will back up its work for at least 12 months/12,000 miles.
If you are asked to purchase an extended warranty, compare costs against benefits.
Remember, you are buying repairs, not a service warranty.
Fifth, call the Better Business Bureau.
They can't recommend a repair shop but they can tell you if there are outstanding complaints against a particular shop.
Lastly, Buy experience.
Shops that have been in business a long time generally have good reputations.