Which Spark Plugs and When to replace?

:
mazda
Does it use:
- Professional Iridium Spark Plug
- Rapidfire Platinum Spark Plug
- Professional Platinum Spark Plug

These were AcDelco - I believe RockAuto has best prices for NGK/Bosch/Denso too.

Which brand should get? Iridium or Plat or Double Plat?

I bought the car with 85k - now 100k in 2 yrs, When is a good time to change? It starts fine.
Thanks
 
:
2010 Mazda 5 Sport
What year car?

I usually look up the part number and buy from the dealer or get the equivalent from the same oem manufacturer.
 
:
'15 6, '06 5
I've had excellent service in late-model Japanese engines (Mazda, Honda, Toyota, and Subaru) from iridium and double-iridium plugs from NGK, Denso, and Autolite.
 
:
2015 Mazda 5 Sport
Yeah, this is the right fit
I do not know if the previous owner changed at 75k - now its 100k - car starts fine.
Wondering if I should wait till 150k?
If you can't tell spark plugs age or condition from its appearance, then change it. It's easier to reset the maintenance schedule to your own than guess what the previous owner did.
 
Does it use:
- Professional Iridium Spark Plug
- Rapidfire Platinum Spark Plug
- Professional Platinum Spark Plug

These were AcDelco - I believe RockAuto has best prices for NGK/Bosch/Denso too.

Which brand should get? Iridium or Plat or Double Plat?

I bought the car with 85k - now 100k in 2 yrs, When is a good time to change? It starts fine.
Thanks
I put 4 ngk iridium and it's great!