Types of Tire Pressure Monitoring Systems

Every vehicle manufactured since 2008 weighing less than 10,000 pounds is equipped with a system that warns the driver of low air pressure in the tires. This system is commonly referred to as the Tire Pressure Monitoring System, or TPMS. When the system senses that the air pressure in a tire drops below a predetermined amount you will receive a warning indicator.

Tire Pressure Monitoring System Malfunction Indicator LampDepending on the vehicle, the low air pressure warning will be either an illuminated light (called a Malfunction Indicator Lamp or MIL), or a message on the vehicle’s information system alerting you to the low air pressure. Some vehicle have both a MIL and a message. If your vehicle has a MIL, it will either be the words “TPMS” or it will be the cross-section of tire with an exclamation point inside of it.

How does the TPMS determine that the air pressure in your vehicle’s tire is low? There are two different type of systems, direct and indirect. (more…)

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Steering Wheel Shaking When You’re Braking?

Shaking Steering Wheel When BrakingYour vehicle’s braking system is one of the most important systems in your vehicle. To put it in more simple terms, if it fails… you crash. The good thing is that in most cases you are given fair warning before the system totally fails. Whether it’s a light on your dash, a pull to one side, a grinding noise, a funny smell or an annoying vibration in your seat or steering wheel there will be a symptom letting you know that something is wrong. In this article I am going to discuss the all too familiar vibration or surging that is felt when the brakes are applied. (more…)

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Aluminum Jack vs Steel Jack

This is one of the most common questions when it comes to buying a floor jack. Which is better, and why? I’m not sure if there is a definitive answer, but let’s dig in a little and see.


The primary reason that floor jacks are made out of aluminum is to decrease their weight. Steel is a denser metal than aluminum so if you were to weight identically sized blocks of steel and aluminum, the steel would weigh more. The question that most people as if a floor jack made of aluminum is as strong as one made of steel. Well, let’s look at that in the next section. Some of the other reasons that floor jacks are made out of aluminum are that it looks cool, can be color dyed, and doesn’t corrode (rust). (more…)

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Can I Use the Differential as a Jack Point

Let me start off by saying that every vehicle is designed differently and you should always refer to your vehicle’s owner’s manual for answers to questions like this. Many times you will find an answer…sometimes you won’t. In regards to this particular question, even when the owner’s manual specifically says not to do it you will find a lot of debate among vehicle enthusiast. The article below is my educated opinion based on many years in the automotive industry as well as considerable research. First of all, some owner’s manuals actually say that it is perfectly acceptable to jack up the rear of the vehicle using the differential or pumpkin. In these cases the answer to the posed question is obviously yes. So what do we do if there is no definitive answer in the owner’s manual, or the owners manual say not to do it. I am not going to tell you its alright to jack up your vehicle using the differential when your manual say not to, but let’s consider a few things to help you make a decision on your own. This will only cover vehicle that have a straight rear axle, not those that have independent rear suspension and utilize constant velocity (CV) axles. (more…)

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How Does a Floor Jack Work?

There are two basic types of floor jacks that you will find inside a typical garage; mechanical and hydraulic. Lets look at each of these separately.

Mechanical Floor Jacks

Mechanical Floor Jack
Mechanical Floor Jack

Mechanical floor jacks use a screw mechanism to apply force to the jack body and lift the vehicle. The short thread distance (or thread pitch) of the screw gives a mechanical advantage allowing heavy loads to be raised with moderate effort. The trade off is that the screw has to be turned many times to achieve a small amount of lift. These are the type of jacks that you find in your vehicle’s roadside assistance kit. (more…)

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Who Invented the Hydraulic Jack?

The year was 1858 when Richard Dudgeon stood at stared at the charred remains of the Crystal Palace, the building that had housed the annual fair of the American Institute the night before. He knew that somewhere under the rubble was his exhibit of hydraulic apparatus. And somewhere under the wreckage were the remains of the steam carriage he had built and displayed as part of his exhibit.

The youngest son of eight children, Richard Dudgeon was born in 1819 in Tain, a small village in the Scottish Highlands. His father, Thomas Dudgeon, had caught “emigration fever” and made several trips to the United States, eventually bringing over his entire family.

Originally settling in along the Seneca Turnpike in the Mohawk Valley at New Hartford, N.Y., Richard quickly realized that that as the youngest son it was unlikely that he would inherit any his fathers estate so he left home at an early age. His journey took him first to Albany where he spent time as machinist apprentice and then on to New York City where he found a job at the Allaire Iron Works where he learned a great deal about steam engine building.

In 1848, Dudgeon married Harriet Loretta Clark. With a new young wife to support and the prospect of children in the near future, he opened up his own machine shop. It was in this very shop that Dungeon began to work on the first of his many inventions, the hydraulic jack.

French philosopher and mathematician Blaise Pascal first described the principle of the hydraulic jack in the 17th century. In 1795, British engineer Joseph Bramah received a patent for “Certain New Methods of Producing and Applying More Power to all Machinery requiring Motion and Force.” It covered the first hydraulic press.

During his time working as an apprentice and with Allaire Iron works, Dudgeon had recognized the need for a portable and powerful lifting device. p to that point, heavy objects were lifted with great effort using inefficient screw jacks. On July 8, 1851, the U.S. Patent Office granted Patent No. 8,203 to Richard Dudgeon for a “portable hydraulic press.” The press used “water or other fluid,” stored in a reservoir was in the device’s head to operate. The “other fluid” was sometimes whale oil and sometimes whiskey. The whiskey was used principally in winter when other liquids would thicken or freeze. This was the reason that the press was given the nickname “whiskey jack.”

Dudgeon’s jack had its share of problems, the most of which was its tendency to be top heavy do the the storage reservoir being located on the top of the device. Although Dudgeon did improve the design of the jack 14 years later, the original jack was such a success in the New York ship yards and railroad shops that it brought him wealth right from the beginning.

Dudgeon went on to invent other things such as the steam carriage, but none of them ever enjoyed the success as the hydraulic jack,

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Tire Sizing and Overall Tire Height Calculation

If you’ve ever wondered what all those numbers mean in a tire size, or how tall a tire will be when it’s mounted on a rim then this article is for you. There are many different configurations of tire sizes out there, but this article is going to focus on what is call a P-metric tire size. It’s the way most passenger and SUV tire sizes are referred to. Here is what one looks like.


explanation-tirewidthLet’s look at each piece of the tire size above individually starting with the “P”. The “P” simply designates that this is indeed a P-metric tire size. The “235” is the section width of the tire in millimeters. The section width is the distance from the outermost part of the tire’s sidewall to the innermost part of the tire’s inner sidewall when mounted on a rim. Keep in mind that the section width is not the width of the tread. The “75” is called the aspect ratio. This number gives the section height, the distance from rim to top of the tread, expressed as a percentage of the section width. In this example, the section height is 75% of the section width. The letter following the aspect ratio designates the internal construction of the tire. In our example, the “R” means that this tire has an internal radial construction (as opposed to bias-ply). The number following the “R” is the diameter of the wheel that this tire will fit on. (more…)

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