[JimD]

I will try this again with some part numbers for my N52.

RealOem lists this as the BMW part number for my plugs if I use NGK (which is what it came with and what I used for replacements) PLZFR6A11S and says the dealer price is $21.32 each.

RockAuto lists the same part number, PLZFR6A11S as a "double platinum" plug and prices it at $8.38 each. (they also have lots of other NGK plugs they list for my engine at prices as cheap as 3.48 each)

Even if I got a 15% discount at the dealership, that is more than twice the price. But roughly an extra $50 wouldn't be a huge hardship either. I just cannot see paying twice as much so the dealership can have more profit.

If NGK were to sell the dealer different plugs with this part number and then market plugs through RockAuto at the same part number, that is fraud. They could be fined or somebody could go to jail. Putting a bmw logo on it does not change anything. I don't think the plugs I pulled from mine had any logo or BMW lettering on them. I think the plugs are the same except for possibly a cosmetic lettering difference.

I think everybody has a right to make this decision themselves. I just refuse to believe there is any benefit from getting plugs from the dealer - other than there should be less chance of getting the wrong plugs.

I also looked at FCP Euro and I may not understand how to use their website but it did not seem like they were showing the right part number. They said they were selling the same as BMW offers but they didn't provide the same part number. Their price was also higher than Rock Auto (by literally a couple bucks a plug).

Jim