I have a 97 SC400 with 70K miles. Any recommendations for which spark plugs to use?

 

go with stock NGKs. They are the best for the type of heat these engines put out. Splitfires are to be avoided as they tend to crack due to the heat.
You don't have to buy the NGKs at the dealer, just your NAPA or over the net.
Good luck!

 

Pick up some NGK PLATINUMS, which is what your car came with from the factory. Never use Splitfires as they are unreliable and wear out easily. Bosch Plats can be used , also the Bosch +4's. Best bet is to use factory on this one. I have tried them all.

 

So, if they're platinum, do I need to change the plugs at 70K miles? Or can I wait till 100K or so?

 

Depends on your driving stlye. If you do alot of highway driving then you can go for an extended period of time. Plenty of stop and go, then you should go earlier. I change plugs on all of my cars from 20k-50k miles just to be at peak. On the SC300 I went 50k because it is such as chore. On my SC400 I went 20k. I am of the extreme when it comes to this. I would recommend every 50k miles. Cap and rotor at the same time also. The factory wires can go 150k-200k miles though should be replaced at 100k.

 

i was thinking of changing my sparkplugs and the cap & rotor of my sc400. do you think it is easy to do if you have the proper tools?

 

Generally what does it cost to service cap and rotor on an SC300??

 

Slick,
I just did mine. It took all of about 15 minutes. You can get the parts on the net or from the dealer (both from the dealer will cost around $60). I had a hard time getting the OEM cap and rotor elsewhere, so I just got mine from the dealer.
If your spark plug wires (they call them "tension wires") are close to 10 years old, I would change them at the same time I change the spark plugs regardless of the mileage. JMHO
good luck!