Rolling resistance

[niv2]

How much difference does rolling resistance of a tyre make in the real world?

I currently have Pirelli Pzero Rosso tyres on my A6 3.0tdi Quattro which have an "E" rating.

I could swap to, say, Prirelli Cinturato P7 Blue with a rating of "B".

Would I realistically see any change in MPG?

[Guest 2]

I went from a Michelin PS3 to a Michelin Primacy on my A3 size 225/45/17, the PS3 had a Fuel Effiency rating of F and the Primacys are C.

Haven't noticed any difference in MPG.

[zollaf]

another load of euro claptrap then is it ????

[niv2]

SAVE FUEL ENERGISED BY LANXESS (http://gm-spritrechner.lanxess.com/public/en_GB) I found this calculator and it seems to indicate savings of around £100 pa, which is not a lot...