The J40 series was produced with both diesel and petrol engines. The F series was a 6-cylinder petrol motor, B series a 4-cylinder diesel, and H series a 6-cylinder diesel. The diesel trucks were never sold to the general public in the United States, though some found their way in as mine trucks. Some engines are similar within their series; for example, the F and 2F engines share many of the same parts. However the H and 2H designations have almost nothing in common.
A pair of jump seats folded behind the front seats, maximizing cargo space compared to the full width folding rear seat of the Jeep CJ series.