they not too bad on fuel if you take it easy an dont boot them about the place cause there is no point you just make more noise. i run mine to the point of oh my god will i make on fuel i reckon i average 26mpg but i live in traffic light city with loads of hills glasgow s.e
1989 Isuzu Trooper 2.6 (3.1 conversion )
1990 Isuzu Bighorn Lotus Edition Hi roof 2.8td
1998 Vauxhall Omega Estate Elite 3.0 v6