Are you tracking expenses for each truck with a separate account? If so, that makes your Profit and Loss statements messier and more complicated than they need to be.

QuickBooks' Classes feature is better for tracking expense for individual trucks. You would use just one set of accounts but apply a truck Class to each transaction for fuel, DEF, etc. Keeps the P&L simple and makes it a lot easier to add trucks (just add one new Class, not a bunch of new expense accounts or subaccounts).

Here's an article on using Classes...and it's even based on a simple trucking company example: Tutorial:  The "What's" and "Why's" of QuickBooks Accounts and Classes http://www.goflagship.com/articles/ckadef.htm.

If you decide to use Classes you might also look at the Expense Allocation videos on this page--particularly the ones for the "Haul-Rite Trucking Co.":  https://bit.ly/2VlR2Pw  ...they show how to get different expense reports on a cost-per-mile-driven basis, etc.