V6 Denso one side, NKG other

Did the 30K maintenance, changed the plugs, and found, as others, the Denso plugs on the passenger side and NKGs on the drivers side. Went to the dealer today for the "special" oil/filter change, tire rotation, fluid check; and asked the service manager why the different plugs on different sides. He said that for the V6 engine, the left bank and right bank heads are made in different factories. One factory uses one brand, one factory uses another. Who knows? I found it interesting. I also found that the NKGs wore a bit more than the Densos , which looked brand new.

 

Just gotta hope the quality control is the same at both factories.

 

true story is

toyota has committed contracts with both from ages ago...so they load them 50/50
to make sure equal parts. No the heads are not made in other factories and no this is not 'waste spark' or any other crap you may read. it is a contractual obligation, plain and simple.

you can use whatever is stated in manual

 

Yep.. that's the way they do them all. I always install Densos in round 2.