Bests & Worsts Reviews from Amazon

This was a awesome tire pressure gauge until it stopped reading the pressure correctly. I ended up driving over 500 miles on low tire pressure because I trusted the gauge over what my truck tire pressure monitor system was telling me. I thought that there was something wrong with my TPM (tire pressure monitor) in my vehicle. I stopped by at a gas station to check the tire pressure and it was 10 psi less than what the gauge was reading. I opened up the gauge and noticed that there are 2 gears that are used to set the position of the needle. I was able to correct the reading by manually turning the needle which caused the gears to skip to the correct position. What apparently happened (at least what I suspect) is that when I released the air pressure on the gauge that the gears skipped and that causes it to display the wrong pressure. Since there is a pin that forces the needle to the zero position if the gear skips in one direction you will not know that this happened. In my case the gear skipped in the direction that forced the gauge to read 10 psi when it should have read zero PSI (after releasing the pressure by the button). This is a fundamental flaw in the design. There should be a way to prevent the gears from jumping. The releasing of the air pressure in the gauge can cause the gears to skip. Needs to be redesigned. I am thankful that I did not get a blow out driving over 500 miles at highway speeds on low tire pressure (remember the Ford Explorer). You should periodically check this gauge with another gauge to make sure that it still reads correctly. Hope this helps and prevents others from driving on over or under inflated tires. Check out the photos of the gears inside the gauge.