how come 7yr batteries never last 7 years or 70,000 mile tires never last 70K miles?

Answer 1

Because the tests to determine those statistics are done under ideal conditions. Like the mpg ratings that the car manufacturer's use and are set by the US government. Each car/truck is tested at a maximum of 55 miles per hour, with the windows rolled up and not using the air conditioning, no fast starts and no rapid stopping. Not the real world driving of the average person. So the 7 year battery is charged and put in an engine compartment or similar device. the car is started once per day (simulation). Not repeated started...not with a clock and computer attached to it all the time. Not in different weather conditions so that the heat and cold that effect the battery are also included. etc.

Answer 2

Car battery's are funny, You won,t need one for years and all of the sudden BAM you need a battery. Here is what happen first you need two types of amps , Cold and Hot cranking amps , If your alternator is working OK . The more you use it the more it wares out .If one of the two goes bad the rest will follow , Remember this when a car is made at a factory the battery's are on pallets and set in ware/houses before they arrive at the factory so think about that some will retain there charge longer if the shipment is faster and the car or truck is delivered sooner you will have a battery for a long time I hope this helped.

Answer 3

The warranties are pro-rated. So after six years it goes bad, what do you do? You try and get the warranty on it. they give you $5 off the price of a new one and they have made another sale.

It could happen.

Answer 4

Lots more electrical equipment in cars these days. Starting your car with all of it turned on wears on the battery.

Answer 5

it all depends how it is used. climate and area you live are some of the factors that could play a role in how long these parts would last.

Answer 6

Because people don't care for their vehicles properly anymore.