Is the speedometer in my 2000 DII auto-adjusting or would I need to get a dealer or an indy rover shop to adjust my speedometer when I get bigger tires? I'd really prefer to have an accurate speedometer where possible, I'm one of those guys who can't handle their clock being off by a couple of minutes, much less the speedo by 5 mph

 

It will not auto-correct. I do not know if the dealer or anyone else can make it accurate.

FWIW, it's not accurate at stock height/tire size anyway according to GPS!

 

Mine was off by 5+ mph on stock tires, went slightly bigger and now it's off by about 2 mph - according to my GPS.

 

I wonder if this would work on a rover:

http://www.superlift.com/accessories/truspeed.asp