The LVT variant with a rear loading ramp was the LVT-4.
The LVT-4 was a World War II amphibious transport vehicle, commonly nicknamed the Buffalo or Amtrac. Its most important design change was moving the engine forward and adding a rear ramp, allowing troops and cargo to enter and leave more efficiently than in earlier LVTs.
That ramp made the LVT-4 especially useful for unloading vehicles, supplies, and assault troops directly onto a beach. It could carry up to 24 passengers and had a road speed of roughly 20 mph, while its tracked propulsion also drove it through water at about 7.5 mph.
The designation can cause confusion. The LVT(A)-4 was a separate armored fire-support version armed with a 75 mm howitzer; the “A” identified an armored or assault model rather than the troop-carrying LVT-4. More than 8,000 LVT-4s were produced between 1943 and 1945, making it one of the most numerous LVT variants.