Think about it. How long has it been sitting there?
When vehicles sit idle for a year, or longer, guess what
happens to the components that have some type fluid in
them?
The Master Cylinder: The brake fluid deteriorates, dries up, and creates some type of fungus inside.
The seals dry out and become brittle, or crack, causing
more particles inside that causes the master cylinder to
not function properly.
Little bits of rubber, and fungi, get into the brake lines.
These particles make their way to the calipers, or wheel
cylinders, causing them to mal-function.
The seals inside the front calipers, and rear wheel cylinders or calipers go through the same drying process.
Plus, the inside of the calipers and wheel cylinders tend
to corrode up, causing the pistons to siege, become locked
at the position they have been in for so long.
Thats just the brakes!
The Automatic Transmission: Transmission fluid does not evaporate, but if the parts inside the transmission do not get lubricated, they tend to freeze-up, so to speak.
There are 1,003,004,005+ parts in an automatic
transmission! 
They all have to be lubricated!
In the valve body there are little trails, tunnels, and
slots that have moving parts.
Just think how complicated that can be when they sit there
for a long time without movement.
Wrap your hand with freezer-tape.
Leave only the index finger out.
Secure the others so as to not let them move a-tall.
Keep it this way for six months.
What will it be like when you remove the tape?
Can your fingers move freely? Can you play the piano?
No? 
We havent mentioned the seals inside and outside of the
automatic transmission.
They have a tendency to dry out also, then become brittle,
and crack.
They loose their goal in life: To seal.
What about the power steering? It does have power steering, dont it? Well, dont it?
If it has a *rack-an-pinion* steering, look out!
Just a *gear box* power steering is bad enough. It has
seals and moving parts, too.
But a rack-an-pinion doesnt have a gear box, it has little
arms inside a cylinder that move in and out as you turn the
steering wheel.
Thats what makes the tires go to the left and then to the
right.
Course, it depends on which way you are turning the
steering wheel.
In the rack-an-pinion you have a lot of moving parts.
Not as many as an automatic transmission, though.
They all need lubrication.
They all get *stuck* when they havent been used in a long
time.
The same with the power steering pump. It has moving parts and seals.
Ill not go into the details, but you understand, dont
you? Say *Yes*!
This doesnt even consider the engine, the water pump, the radiator, the water hoses, heater core, the fuel system, or even the air conditioner.
This could be a large manual!
But you get the picture, dont you?
Now Im not saying you should never buy a used vehicle.
What I am saying is consider the length of time it has been
sitting up.
On the used car lots most of the owners crank their
vehicles at least once a month and move them around on the
lot.
That helps!
It keeps the parts lubricated.
If you are considering a car or truck from them, its
probably okay.
Beware, though, of those that have been sitting up and
havent been moved on its own for a few years.
Hope this helps you with your next purchase!
Tommy Sessions has been in auto repair since 1970. He publishes Auto Repair Answers Newsletter so you can learn how to keep your vehicle looking new, running safely and efficiently, while you save money and time…also, learn how to avoid shop rip offs. Don’t be at the mercy of the dealerships and auto repair shops…they will have more respect for you.
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