Hey buddy. I have the same problem on an MXS, bad fuel milage. I flashed from 475 to 625 and no change in the fuel milage. Under 400k miles on...
I think they all work. You every brand has it's quirks that you have to learn to live with.
Peterbilt. Class pays.
Hard to say.
We make the wide stainless steel fuel tank staps with the t bolts. Contact me for info.
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