From the end of the Korean war until the the 1991 Gulf War the US only had two armour on armour engagements. The first in 1965 was a bit one sided. During the Dominican Republic civil war a US M48 Patton found itself in a battle with a rebel Stridsvagn L-60. The L-60 was a solid tank when it was designed in 1934. The one sided battle ended as we might expect. The other battle happened four years later on a very different battlefield.
In the Vietnam War the North Vietnamese Army moved its troops and supplies down the famous Ho Chi Minh trail. When this turned to re-enter Vietnam the US built numerous firebases along its routes to halt supplies flowing to the fighting in the south. One of these was a special forces camp at Ben Het.
Manned by US forces and Montagnards, the firebase had two M42 Dusters and several batteries of artillery. B company 1/69th Armour was also deployed under the command of Captain John Stovall. A single platoon was placed at Ben Het, the other tanks were spread out along the only road link to provide security and quick reaction forces. From the bases’ west hill the US could call down artillery or air strikes on any suspected movement of NVA supplies coming off the Ho Chi Minh trail. The NVA decided to smash the position. Starting on February 23rd the NVA began to heavily shell the firebase at Ben Het. Sometimes shells would be arriving at the rate of one every 45 seconds.

The artillery pounding came in part from Base Area 609, a heavily fortified NVA area. The position was hit by air strikes on the 24th and 25th. But due to an ingenious trick they failed to cause any significant effect: the NVA had mounted its guns on rails, and given each gun a cave into which the artillery piece could be pulled backwards into when danger threatened. The entrance to the cave had blast doors that could also be sealed.

Despite that the artillery emplacements revealed their positions by the muzzle flash when fired, giving the firebase a warning of an incoming barrage. The US tankers also tried to fire long range at Base 609 with concrete piercing shells guided in by spotter aircraft. All this had no effect on the bombardment.
The NVA fire wounded the platoon leader of the M48's stationed at Ben Het, as he was evacuated Cpt Stovall moved his command post to the base to take over command.

At the beginning of March the bombardment stopped. However at 2200 on the night of the 2nd vehicle movement and engine noises could be heard from outside the wire. Despite using their night vision devices nothing could be seen, and after 20 minutes the sounds ceased. The US intelligence simply dismissed them as bulldozers. A Montagnard patrol later reported a confirmed visual sighting of a tank.

The 3rd of March was very quiet, and life continued as normal. In the evening an observer was directing a Spooky gunship against targets in the vicinity, apart from that there was no firing.
Shortly before 2100, as the night began to draw in it began to get foggy. With limited visibility the Spooky departed for home leaving the valley below Ben Het in quiet.

A few moments later the NVA began firing from a pair of recoilless rifles, pecking at the perimeter of the firebase. At about 2130 a whirlwind of fire swept the firebase as the NVA forces opened up in earnest. Nearly 700 shells were fired in half an hour. At 2200 through the concussions of the shell impact the defenders could hear the "Bulldozers" again. Peering through the night sights on their tanks or starlight scopes, even with the infrared searchlights on the tankers couldn't see anything but the trees and fog. To make matters worse some of the tanks had no IR searchlights.
Suddenly about a kilometre out there was a flash and a a detonation. One of the NVA tanks had hit a anti-personnel land mine and had been immobilised. The NVA tanks opened fire lobbing HE shells at the hilltop, the immobilised tank opened fire first and its shell landed short of the firebase. The M48's returned fire, one tank fired at the muzzle flashes, the second round it fired hit an enemy tank which turned into a fireball.

Meanwhile Mike Linnane, one of the US special forces A-Team members had grabbed his radio and called out to the Spooky that had just left the area.
"You've gotta come back, we have tanks down here!"
After a stunned pause the gunship replied that he was on the way back. When the gunship arrived over the battlefield he began dropping huge amounts of flares to illuminate the area, as well as making attack runs.
By now the M-48's were also using their machine guns to strike back at the enemy infantry, whom were pressing closer and some had reached the wire. As the conditions on the battlefield grew brighter from all the flares both from the Spooky and the defender's mortars, one of the NVA tanks spotted an M48. As chance would have it Cpt Stovall was just climbing up the back of the M48 when the NVA gunner fired.

Accounts differ, one account says the round hit the glacis plate, another said the loaders hatch. Wherever it hit, both the driver and loader were killed, the tank commander was blown out of his hatch and landed ten feet behind the tank and Cpt Stovall was seriously injured by shrapnel.

Spare tank crewmen from Cpt Stovall's command post had been helping feed the artillery and mortars by heaving shells. When they saw what had happened they raced to the M48's position, and formed a scratch crew to continue to fight the wounded tank.

At this time another tank was brought into action, normally facing a different direction it had been unable to engage the main enemy attack. Again sighting at the muzzle flashes its gunner managed to destroy another NVA tank. As the battle wore on the tanks began to run out of ammunition and were reduced to firing concrete piercing rounds. One APC was spotted and pummelled into oblivion by several of these shells.
At about midnight the NVA began to break off the attack. The Base at Ben Het had held for the loss of three killed. The next day inspection of the battlefield discovered what the NVA tanks had been. A pair of PT-76's lay smoking below the base along with the hulk of a BTR-50.