housecrusher

i have two roll offs they lack big time in power one is a 03 and the other is 04 they both have a 400 in them there fuel hogs also and they are sluges i have a 99 r model dumptruck that smokes them when th dumptruck has 25 ton load and the rolloffs have 10 tons on them what can i do to get more power

i have the gutless powerless 400 hp macks i found out that the motors are A I 400 aset what does that mean are they they etechs are tey e7 s is there anything i can do for more power let me know thanks

they 2004s how do i tell if they are e7s and its been to mack about five times for the lack of power they say its at its max for the specs that mack has

i have two cv713 with 400s and they are powerless gutless trucks there used for rolloffs so there not pulling much weight the only thing fast on these trucks are the paint thats peeling on there roofs my dad has always was pro macks but after these two i had engough of them any thing out there that i can do to crank up the power