Spark plug Motorcraft or OEM Mazda

Modern Ford engines tend to work best with Motorcraft or NGK spark plugs.

Motorcraft is all I use , heard to many stories about aftermarket plugs causing misfires

I do run Motorcraft plugs because they seem to crack a little less than the Autolites.

anecdotally, my truck was at 226k when i changed the plugs. motor craft plugs coated, no anti seize, torqued tighter than advised. probably 20lb ft. 2 rear plugs were originals. i’m now at 235k and nothing wrong yet.

I’ve found that Motorcraft platinum spark plugs work best in my 1998 Ford Ranger. I tried Bosch plugs and it ran terribly. Nothing but Motorcraft from now on (for Fords).

I however replaced mine with motorcraft and do not have pinging anymore but still run 91 octane as 93 isn’t common in socal.

On any of the gas trucks with the "modular" engine family (4.2 V-6 and 4.6/5.4 V-8) it seems like if you use anything other than Motorcraft spark plugs and coil packs, the engine won't run right at all, no matter the brand.

I always stick with Motorcraft double platinum, or Autolites if they aren't available. No reason to get fancy with sparkplugs.

Rx-8 in 3years just did maintence and ned sparkplugs 0 problems.

Has anyone tried the Motorcraft SP594 plugs? They supercede from the SP542, which is said to be a 1 step colder plug for our cars. Currently running NGK 6510s but i think i got a "fake" set as i paid like $30 from Amazon for them. The SP594s I can get for $41 from Ford... so anyone have good results?