How easy is DIY for the spark plugs?

[jadmt]

I just took about 45 minutes and changed my plugs...they looked really good at 39,000 miles...I could have probably left them in for another 10,000 or longer but once I pulled them I just went ahead and changed them. I ordered my plugs from Mazda swag so it ended up costing me $108 and 45 minutes...super easy to do and no rubber hose needed . just a 14mm spark plug socket and an extension....

 

[Mazdiod2]

I think one of the reasons plugs need to be changed is that the metal electrodes erode to the point that the gap is too large to make the electrons jump it, so no spark. Can you tell any difference in the size of the gap between the two plugs?

 

[jadmt]

I think one of the reasons plugs need to be changed is that the metal electrodes erode to the point that the gap is too large to make the electrons jump it, so no spark. Can you tell any difference in the size of the gap between the two plugs?

no difference..both would pass a .028 wire feeler gauge and neither would pass a .030 wire feeler gauge..I am guessing both would pass a .029 but don't have one of those.