I'm replacing the secondary tensioners on my 2000 XKR and will also be replacing the plugs. I found these plugs on ROCKAUTO for $41.59 shipped plus there's a factory rebate of $2.00 per plug. That's everything for around $26.00. Awesome price for 8 Iridium plugs.

 

I bought those exact Plugs from Rock Auto also and they looked identical to the OEM Plugs that I took out. The Autolites work Fine.

 

Great! I just found them at Advanced Auto for $38.00. You buy them online and use P20 code and you get 20% off and then you can pick them up at the store. That code works for everything they sell. Then I will use the rebate to get another $16.00 back.

 

I replaced mine with the NGK Iridium plugs and it actually increased my mileage a bit. Iridium plugs are recommended and have noticed that other MFGs are starting to make them. Iridium is the best way to go.

 

I just bought AutoLite double Platinum XP 3924, should I be alright?

 

Actually the XP 3924 is Iridium, Not Platinum.

XP 3924 is the correct Iridium plug for a 2001 N/A XK8.

 

FYI Folks:
I know that this is an old thread, but I just received my 8 Autolite XP3923 plugs from RockAuto.com for just under $2.00 a plug including Autolite rebate ($2.50/plug),R-A 5% discount, and USPS shipping.