Complex sentence: Rebadged variants of the second-generation Ranger were marketed by Mazda as the B-Series with Mazda using the engine displacement in their model designation; the B2500 had a 2.5 L I4 engine and the B4000 has a 4.0 L V6.
Split into simpler sentences: Rebadged variants of the second-generation Ranger were marketed by Mazda as the B-Series with Mazda using the engine displacement in their model designation. Thus, the B2500 had a 2.5 L I4 engine and the B4000 has a 4.0 L V6.