Standard interval is 60k, except for CA where it is 100k. No difference between parts, trucks, builds, etc. When asked, my local stealer tried to tell me it was because our climate in OH is harsher for wear and tear than CA. I told him rubbish of course and that even if true, there are other climates more like CA.

Bottom line looks that CA mandated 100k warranty for whatever reason and Mitsu must have done the math on chance of failure and rusultant warranty expense and said okay.

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
Her Truck: 03, 3.8, 20th Anniv, 65k
Daughter's: 06 Eclipse, Keeping it Mitsu!
FSMs: MitsubishiLinks.com