The engine in the GTH-1056
Fitment for the GTH-1056 centres on the Perkins 1204E-E44TA: 4.4L / 268 cu in, 4-cyl inline, 105 x 127 mm bore x stroke, about @ 2200 rpm, Tier 4 Final. Serial number on the block settles the exact version. New-surplus and rebuilt stock ships from Houston.