Mack Military - T8 Series Doubled-Ended 8x8 Tank Transporters

[kscarbel2]

The Mack Trucks T8 series of tank transporters resulted from a new U.S. Army requirement in 1942 for a double-ended design with significant off road capabilities. Once again, the U.S. Army gave the challenging assignment to Mack Trucks.

Mack Trucks produced three Mack T8 series tank transporter during the 1945-1946 period and all were extensively tested at Aberdeen Proving Grounds in Maryland.

The Mack T8’s front and rear four-wheel drive tractor modules were powered by two 1,090 cu.in. (17.8L) 240 horsepower (@ 2,000rpm) Hall-Scott 440/441 engines coupled to Spicer three-speed torque converter transmissions. Steering was accomplished via differential control. Each unit had a 30-ton winch and 200 gallon fuel tank. Minimum ground clearance at the axles was 20 inches. The Mack T8 could carry a 35-ton payload cross-country and weighed 99,100 pounds. Tires were 24 ply size 21.00-28.

[kscarbel2]

A more powerful version, the T8E1 (U.S. Army 5137225), was powered by two all-aluminum 1100 cu.in. (18L) 450 horsepower (@2,600rpm) Ford GAA V-8 tank engines featuring dual overhead camshafts and 4 valves per cylinder. Paired with Allison Torqmatic transmissions, it had a top speed of 31 miles per hour.

The Mack T8E1 could carry a 40-ton payload cross-country and weighed 92,400 pounds. The tire size grew slightly from the original T8 from 21.00-28 to 21.00-29.

The driver of the front unit had control of the power and braking for both units (the rear driver could override the controls if necessary). While the front unit could be detached, it was the rear unit that was designed to be detached in normal use for loading and unloading.

Note how the "E1" variant of the T8 series has a radiator that protruded from the front cab panel.

[kscarbel2]

A further development of the Mack Trucks T8 series was the experimental T9, resulting from. In 1950, the T8E1 was adapted to carry the army’s 280mm atomic gun carriage (it fired atomic shells), resulting in the Mack T9. Length increased from 60 to 71 feet.

[mackdaddy]

very interesting

thanks for sharing

[DailyDiesel]

So what do you think happens to all this stuff when the Army doesn't adopt it?

[rsb502]

De-mil, scrap or a museum

[rsb502]

Apparently the cannons at Ft Will and Aberdeen still have the Mack T9 with the cannon, supposedly 20 were built and were fielded in Europe and Korea during the cold war.

[rsb502]

Ft. Sill, and they are modified or updated T9's with different 375hp engines and std Mil Spec heavy truck wheels and tires for parts commonality.

[rsb502]

More research shows that the M249 front and M250 rear tractors for the M65 cannon system were actually KW's, the Macks were used to start the project and KW built 33 pairs of the tractors for the cannons when they were put into service. Seems odd KW built 33 pairs and they supposedly only built 20 cannons and the tractors are harder to find than the cannons but crazier things have happened.

[mack mhe9]

Been to Aberdeen a lot and there's stuff all over that place. Just never allowed to stop and take pics. Go figure.

[kscarbel2]

Speaking of the Kenworth-produced M249 (front unit) and M250 (rear unit), we're talking about the T10 (the gun it carried was designated M65/T131). While it is reported that only 20 of the atomic cannons* were produced, noted military vehicle historian Fred Crismon states that sixty-six of the 85 ton T10 gun carriages were produced in 1952-1953, and many were stationed in West Germany from 1954 to 1961.

Each unit was powered by an 895 cu.in. 375 horsepower Continental A0-895-4 horizontal opposed-piston engine coupled to a 3-speed manual transmission with an Allison torque converter.

As with the Mack T8 Series, the forward driver controlled both power and brakes.

* The cannon could fire both conventional and W9 atomic shells. It had a range of 35 miles with an accuracy of 20 yards. The 280mm cannon was based on the German Krupp K5 railway gun captured by the Allies at the end of WW2. Twenty eight were produced and two nicknamed "Anzio Annie" and "Anzio Express" by Allied troops made quite an impression in January 1944 when they began shelling the Anzio beachhead during Allied invasion of Italy from 20 miles away. The Allies again felt the lethal end of the German 280mm K5 cannon in June 1944 during the invasion of France.

A little known fact is the successful firing of a W9 nuclear shell in Nevada in 1953 is credited with bringing an end to the Korean war.

[kscarbel2]

One of the largest ordinance transporters of the U.S. military was the Terex 8x4 model 33-11 MX missile transporter produced in 1979. Very little information is available. The engine was rated at 1,000 horsepower.

[41chevy]

Been to Aberdeen a lot and there's stuff all over that place. Just never allowed to stop and take pics. Go figure.

A lot of the referbished armor and weaponry has been moved to Fort Lee, Virginia, some is on loan to The American Armor Museum in Virginia a few tranport vehicles were loaned to the U.S. Army Ground Transport Museum in Virginia and some of the WWII German Armor is on permanant loan the the German Armor Museum in Munster, Germany. What it left there is not money to "sanitize" it per new EPA regulations for Lead, Asbestos and Depleted Uranium contamination of the Iraqi vehicles. . .SAD

[RRJordan]

There is a little confusion above about Anzio and Normandy.

[Green Dash]

Excellent info and history, gentlemen. Thanks for sharing.

[kscarbel2]

There is a little confusion above about Anzio and Normandy.

Please forgive me. I'm going to blame it on jet lag. I corrected it.

[vision386]

Great article,thanks for posting! I have always been interested in WWII,and its many vehicles,and always wondered about the operation of tanks and their crews,i found this video on the driving of a Sherman M-4 I thought might be of interest. For those un-aware,the Sherman was a highly inferior tank to comparable German units,basicly a deathtrap! under-armored,under-gunned,and fueled with high-octane gasoline. But Mack did make the transmissions for both early M-3 and M-4's musta' been quite a workout to run a tank! I give the WWII tank crew vets all the admiration and respect I have! Truly some of the most un-sung heroes of the war...........................Mark

[kscarbel]

On 10/25/2013 at 7:14 AM, Vision 386 said:

Great article,thanks for posting! I have always been interested in WWII,and its many vehicles,and always wondered about the operation of tanks and their crews,i found this video on the driving of a Sherman M-4 I thought might be of interest. For those un-aware,the Sherman was a highly inferior tank to comparable German units,basicly a deathtrap! under-armored,under-gunned,and fueled with high-octane gasoline. But Mack did make the transmissions for both early M-3 and M-4's musta' been quite a workout to run a tank! I give the WWII tank crew vets all the admiration and respect I have! Truly some of the most un-sung heroes of the war...........................Mark

Note that the Sherman on the Mack T8E1 is a late model with HVSS suspension (horizontal volute spring suspension) and the 76mm high velocity gun.

The Shermans evolved into a formidable weapon as a result of British modifications. The Brits needed more tanks but recognized the Sherman's deficiencies that you speak of (The British were well aware of the weakness of U.S. tank design, having already suffered heavy losses with U.S. M3 "Grants" against Rommel's Afrika Korps). The most important British modification was replacement of the short 75mm cannon with a lethal long barreled 17-pounder anti-tank gun that could take on most German armor. It could penetrate more armor than the 88mm in the German Tiger.

England operated 17,184 Shermans. Unlike gasoline-engined U.S. Arrmy Shermans which earned the name "Ronson Lighters", many British Shermans received under Lend-Lease had 410 horsepower Detroit Diesel model 6046 12-cylinder engines, essentially two paired 6-71 engines (Sherman Mark III/M4A2). The Russians, whose tanks were all diesels, received M4A2s as well. The U.S. Marines did receive a few M4A2s (less than 200) for use in the Pacific alongside gasoline-powered M4A3s.

A small volume of Lend-Lease Shermans (M4A6) were fitted with 450 horsepower RD-1820 radial diesel engines, a Wright R-1820 aircraft engine converted to diesel by Caterpillar.

Mid-way thru the war, U.S. Army Shermans were upgraded with the heavier T23 turret and a 76mm high velocity gun, giving our guys a chance (but still unequal to the British Sherman "Firefly" variant).

With its early weaknesses resolved, the refined M51 Super Sherman was being used successfully against significantly more modern Russian T54 and T55 tanks as late as 1973 by the Israeli Defense Force.

The Israeli "Super Sherman" mounted a deadly French 105mm Modele F1 gun in a much modified turret, with 460 horspower Cummins VT8-460Bi V-8 engines and HVSS suspension.

[countryboy5487]

Very interesting articles and info on vehicles ive bever heard of and i never knew the shermans were modded by the brits. I cant imagine how loud it would be inside a tank with a v12 detroit behind me running wide open!

Eric