看磨損是否對稱,看紋路深淺測量結果

一般新車  3-4年硬件問題相對少見，所以主要看輪胎紋路磨損深淺。自己去買一個tire tread gauge很便宜，自己測量很簡單，自己測量也放心。你說跑高速多  ，所以建議你自己 經常檢查，低於 2/32就該考慮更換輪胎，以減少打滑幾率。

如果你的輪胎以前定期rotation，那一般4個 磨損接近，4個輪胎同時換最好。如果 4個磨損差別大，那  最好2個輪胎一起換，以後注意定期做rotation。


http://www.baytires.com/faq
Using depth gauge:
With a depth gauge you can get a more accurate measurement of the tread. Procedure is standard: line up the gauge over the tread and push the center into the groove between the tread.



The tread depth should be above the legal minimum of 1/32nds across three quarters of the tire.



Quick Check:
A quick visual check of the tire depth can be made by looking at the tread wear indicators. Tire worn down to the level of the indicator may have 2 to 4/32nds of remaining life, depends on manufacture.



We use the following images to help you quickly identify tread condition of used tires.

(4/32nds) 40% remaining tread life



(5-6/32nds) 55% remaining tread life



(7-8/32nds) 75% remaining tread life



(9-10/32nds) 95% remaining tread life

Used Tire Maintenance

Tire pressures, including the spare, should be checked at least once per month before driving, when the tires are cold (after the vehicle has been stopped for three hours or driven less than one mile). Do not reduce air pressure when tires are hot. Use professional tire gauge to check pressure and maintain it at the level recommended by the vehicle manufacturer. If a tire loses more than one pound of air pressure per month, have it checked for leakage by your dealer or professional tire shop. Proper inflation pressure is very important to tire durability tire life, comfortableness, and vehicle handling, therefore you should always maintain the correct inflation pressure in your used tires according to your vehicle manufacturer's recommendation. In addition, your vehicle has a Tire Information Placard, which indicates the proper tire size and inflation pressure for your particular model car.

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http://www.gemplers.com/tech/tire-tread.htm

Step 1: Push the plunger all the way down.				Step 2: Place the probe into the tire groove and push down on the gauge. * Do not probe on a raised surface or   a tread wear indicator.
Step 3: Lift up by the base of the gauge to check the gauge reading.				Step 4: The higher the number the more tread depth on the tire. This gauge reads in 32nds and millimeters.
		• Check the tire in the center and outer grooves in four places in each groove equally   spaced around the entire tire. • For high-speed highway tires, always check your state’s vehicle code for   minimum allowable usable tread for highway use.