Originally Posted By: Donald
I think its good to use what you list for 7500. Its more than a matter of how much crud they can hold, its that they have better filtering capabilities.
I agree that there's more to the premium filters then just their dirt holding capacity. The higher quality filter media also filters better.
You can safely use the M1 and K&N for 2x 7,500 mile intervals, which will equal to the 15k miles that the filter is designed and rated for. This will help you squeeze out EVEN MORE value outta the filter.
I personally buy mine when they're on sale at AAP, purchase in bulk (5-10 filters) use a discount code and they come out to be like $6 each! At that price, i can afford to toss them every 3k miles but i still use them to the fullest and only trash em after they've gone through 15k worth of filtering. (This could be between two different engines as well).