I have a new 2012 2500 and installed 18" rims with 33"S I am not familiar with tpms system but it is showing low air (I'm running 65 lbs Tire recommendation) and the rear 2 are flashing is there anything I can do to stop this, also averaging 12.5 mpg any recommnedations without voiding
the warranty Thanks for anyones help

 

When they installed the new rims did they put the TPMS sensors in them?
When they installed the 33's was the truck programmed so that the speedo/odo and MPG reads correctly?

 

Yes the sensors were taken out of stock wheels and installed in 18" wheels They say there was no reason to recalibrate sppedo

 

Seems like they may have busted the sensors if they put them in the new wheels and they are not working. What size were the stock tires?