Tires: Inflation pressure conflict, tire placard, general grabber

Question
I have a 2001 Nissan Frontier XE King Cab that I use mostly to commute back and forth to work.

I replaced the original P225/70R15 tires with new General Grabber HTS 225/70R15 tires (note the missing "P").

The tire placard on the vehicle calls for 26psi in both front and rear tires. My mechanic says that's way too low for these tires and recommends 36psi.

I don't really know who's right. Could going from P-metric to metric make that much difference in inflation pressure? How much air should I put into these tires?

Thanks,
Bill

Answer
Bill,

No, changing from P metric to Euro metric doesn't change the pressure recommendation.  It is unfortunate that your mechanic doesn't understand how this work - but he doesn't.

If you want more detail on how this works:

http://www.geocities.com/barrystiretech/loadtables.html