I recently viewed a YouTube video of 4 grown men changing a tire on a ML350 and realized that with most individuals, this can be a perplexing and dangerous situation. However, with a little preplanning and knowledge, this is a task anyone can accomplish.
We know the simplest way to change a tire is to have someone else do it for you. A call to a roadside service or a Hero unit will work if you are willing to wait, to pay for it, and if there is one available at your location. With preplanning and a review of the techniques, this chore can be accomplished. But before you begin, make sure you have all the necessary items. The first and most important item is an inflated spare tire.
The Evolution of the Spare
Originally, the spare was exactly that - an additional wheel just like your others - with the same size tire that you could drive for thousands of miles. Obviously, you would want to get the damaged tire fixed or replaced, but you did not have to do it within the current standard of 50 - 150 miles. "Space saving" tires were first offered on the SLK, C-Class Coupes, and the CLK. In 1998, with the SLK and CLK models, the wheel was basically the same size, but the tire was collapsed to fit in the trunk. Your chore as the consumer was to inflate the tire with a compressor - which came as standard equipment.
Another type of "space saving" tire appeared in 1998 on the ML320 model. This was a "skinny" tire, which was already inflated and could be installed without any additional inflation. These "skinny" tires were to be used only for a limited amount of mileage. Often, owners would drive on them for several hundred miles before changing back to the original tire - not a very safe thing to do!
Finally, the spare has evolved to "no spare at all". These cars, usually high end vehicles such as the S-Class, have "run-flat" tires. With the run-flat tires, you can drive a whopping 50 miles without damage to the tire. You are not to drive over 50 mph, and if you are pulling a load, you should never exceed 18 mph! Take it from personal experience, run-flats are the worse idea in modern automotive technology. Mercedes-Benz states the run-flat will give you more luggage space and improve gas mileage. What BS! If you want to replace the run-flats with conventional tires, all you need is a can of sealant and a compressor.
Sorry, I have strayed from the fundamentals of changing a tire!
After you make sure you have your inflated tire, the next important item is the jack. For years, Mercedes-Benz used a very efficient item that was inserted into one of four jack-points, and you turned a handle in a circular motion. (Most of the early jacks had a handle you rotated to elevate the car.) This jack transitioned into the scissors jack, because some MB models were getting so low to the ground, and it had a protrusion which fit to the chassis of the car. With the scissors jack, you have to get on your hand and knees to locate the recess, and the jack is then positioned at a 45-degree angle.
Next item on our tire changing quest is the locating pin. This item is in the tool kit and will screw into a lug opening. This gives you the ability to slide one of the 5 openings onto this "pin" to make the spare more stable. This item will also make your job 100% easier.
Finally, we need a lug wrench. Mercedes uses a 17mm lug bolt and supplies a lug wrench in the toolkit. The one supplied, however, is inadequate. What is needed is a lug wrench that is longer - or a way to make one longer. W140 cars did come with a longer lug wrench.
Lastly, use common sense!