yes, the software problem in 09's was corrected before the 10's hit the dealers. Should be accurate to within 1mpg based on experience of myself and others. Did you get the 09 base reflashed?

 

nope, but i dont think my sister quite cares, but i will let her know...

 

Everything I've read says they are right on. The '09's with the update are also quite accurate. Remember however that fuel pump inaccuracies will always play a role so if it's within .5mpg, It's probably right on. It will probably be slightly high one fill up, slightly low on another... but the average should come out to be right on. The 2009's were ALWAYS higher than actual economy - this is where the problem was.

~SB

 

^i had my 2009 updated but it seems that the gauge is still off by 2-3mpg every fill up...but sometimes it is accurate. did the dealer just BS me and not actually do the TSB?

 

Seems to be. Just filled up for the second time. First fill up the gauge was 2% lower than manual calculation, second it was 2% higher... So, it's seems pretty accurate.

Other posts in here support that, saying it was a software issue that was resolved.