When To Change Spark Plugs

MAGOO1 · November 3, 2011

Hmmmmm.....guess since I'm at 270k, I ought to change plugs and wires.......truck's never had them changed!

wavery · November 3, 2011

With getting feedback from quite a few mechanics, every single one of them said to get them out of there well prior to 100,000 miles, and suggested that the max they may consider telling a customer to go is 75k. The biggest issue they run into is having plugs "welded" in when they try to remove them at 100,000 miles. Some times this will cause the plug to break or even the threads to strip which causes a whole new set of issues. They suggest removing the plugs at about 50,000 miles to inspect them and see how they are doing. Also, using anti-seize is a big, no no. Causes more problems.

IMO..... That's an old wives tale..... Some think that the plug may not obtain a proper ground with the ant-seize. Simply not true.

The 1st time that you pull the threads out of an aluminum head, you will wish that you would have used anti-seize compound.

desrtrat · November 3, 2011

With getting feedback from quite a few mechanics, every single one of them said to get them out of there well prior to 100,000 miles, and suggested that the max they may consider telling a customer to go is 75k. The biggest issue they run into is having plugs "welded" in when they try to remove them at 100,000 miles. Some times this will cause the plug to break or even the threads to strip which causes a whole new set of issues. They suggest removing the plugs at about 50,000 miles to inspect them and see how they are doing. Also, using anti-seize is a big, no no. Causes more problems.

IMO..... That's an old wives tale..... Some think that the plug may not obtain a proper ground with the ant-seize. Simply not true.

The 1st time that you pull the threads out of an aluminum head, you will wish that you would have used anti-seize compound.

so true..when applying it just need a lite coating on the threads..your not putting frosting on a cake. and a lite coat of dielectric grease in the plug boots makes life so much better next time..

wavery · November 3, 2011

With getting feedback from quite a few mechanics, every single one of them said to get them out of there well prior to 100,000 miles, and suggested that the max they may consider telling a customer to go is 75k. The biggest issue they run into is having plugs "welded" in when they try to remove them at 100,000 miles. Some times this will cause the plug to break or even the threads to strip which causes a whole new set of issues. They suggest removing the plugs at about 50,000 miles to inspect them and see how they are doing. Also, using anti-seize is a big, no no. Causes more problems.

IMO..... That's an old wives tale..... Some think that the plug may not obtain a proper ground with the ant-seize. Simply not true.

The 1st time that you pull the threads out of an aluminum head, you will wish that you would have used anti-seize compound.

so true..when applying it just need a lite coating on the threads..your not putting frosting on a cake. and a lite coat of dielectric grease in the plug boots makes life so much better next time..

I lot of people think that the anti-seizing compound works by coating the threads so that you eliminate the metal to metal contact that can cause galding of the threads. That's not the way that it works.

If you just screw the threads into the whole with nothing on them, there will be an air gap between the threads because they never fit as an exact match. If they did, you wouldn't be able to turn the object in the threaded hole.

The ant-seizing compound is designed to fill that air gap and decrease the chance of moisture getting between the threads and causing corrosion. The corrosion would fill the gap if the compound was not there and make it nearly impossible to turn the object out of the threaded hole. This is especially prevalent when you have dissimilar metals because the moisture will cause electrolysis to occur.

The tips of the threads still make 100% metal to metal contact and the ground is still secure. What is eliminated is the moisture.