Mazda Forum - Mazda Enthusiast Forums - Expected RPM at 5th gear

Hi all! Recently bought a used 2007 year Mazda 3, 1.6L petrol, 5 gears, manual transmission.

For me, driving experience has been quite smooth, but I've noticed that at high speeds, the RPM is higher than I would expect. When I am driving at 100 km/h (62 mph) in 5th gear, the RPM is about 3000 while cruising. For me, this seems to be a suspiciously high number. Also, the petrol usage is quite high. I measured it to be 8.5 l / 100km (27.7 miles per gallon), although I drive half of the time on highway and half in the city.

Can anyone here share their experiences? Are these normal numbers that I am seeing? Or do they indicate that there might be some issues with the engine that cause higher-than-average petrol usage and lower the engine performance?

Cheers,
Rauni