Another '04 Granite With 460 No Power

[dog bone]

This is my sixth week with this truck. E-7 460, 18 spd, and 4.73 rears - thought this would make a nice lowboy truck. I love everything about it except the motor, slow throtle response kills me on any hill. Boost will get up to 32 psi once the rpms are 1600 and up. I understand being slow with a heavy load (almost always 100k - 130k) but even empty it falls on its face. Also throwing a 8 - 4 code, but only at start up, light will go out after warm up. Im hoping this is my problem but open for any suggestions. Maybe a hotter program?????

[Supertrucker]

We're experiencing similar issues with our '07 Granites we bought with the 405hp MP-7's with the 10 speed. We traded two Ch's with E7 355/380's and never had a power issue. We are also seeing poor fuel mileage compared to the Ch's.

[Mackpro]

This is my sixth week with this truck. E-7 460, 18 spd, and 4.73 rears - thought this would make a nice lowboy truck. I love everything about it except the motor, slow throtle response kills me on any hill. Boost will get up to 32 psi once the rpms are 1600 and up. I understand being slow with a heavy load (almost always 100k - 130k) but even empty it falls on its face. Also throwing a 8 - 4 code, but only at start up, light will go out after warm up. Im hoping this is my problem but open for any suggestions. Maybe a hotter program?????

Take it to a Mack dealer and tell them you need the "throttle responce" file flashed on your VECU and any available data files and software for the EECU. The download from Mack is free to the dealer, you should only have to pay for the time/labor to install (2 hr usually) They will have to call Mack tech support and have them turn it on. We do this about once a week and it makes a big difference in power and of course throttle responce between the gears. The gear ratio is perfect for tall 24.5 tires. You might change the #4 EUP if after the downloads dont help enough. The new EUP must be calibrated at a Mack shop to be right.