Today in WW II: 21 Jan 1942 Rommel's second offensive drives the British 8th Army back almost 300 miles, halting on 4 Feb between Gazala and Bir Hacheim, 30 miles west of Tobruk, Libya.
M870A1 Semitrailer, Lowbed: 40-ton Construction Equipment Transporter
Semitrailer, Lowbed: 40-ton Construction Equipment Transporter M870A1.
The M870A1 semitrailer is an improved version of the M870 semitrailer with the same mission of transporting construction equipment and material. It is towed by prime movers such as the Marine Corps MK48/16 LVS Semitrailer Adapter configuration. The semitrailer can transport a payload of 40 tons cross-country at 20 mph and on highways at 40 mph.
The gooseneck of the M870A1 semitrailer drops down to form a ramp for loading and unloading of equipment. To widen the bed and to help stabilize and support the load, twenty-four permanent outriggers are stored in an open stowage compartment on the gooseneck behind the air and electrical connectors. A spare tire is mounted on the rear deck of the vehicle. The prime mover supplies brake air pressure and control of the brakes.
The M870A1 has five D-rings on each side. It also has two D-rings and two 17-ton shackles on the cargo bed and two D-rings and two 17-ton shackles on the gooseneck.
M870A1 Changes from the M870 Semitrailer
The design of the M870A1 was changed so that the M870A1 cannot be loaded or unloaded from the rear as can the M870. In addition, the M870A1 semitrailer has different dimensions than the M870 and changed from the M870 in the following items:
||Yes, two 24V
||Differences in clearance lights, reflectors, rear stop/turn lights
||Disk, ten studs
||Spoke, six studs
||Goodyear K type
Information in this table from TM-5-2330-378-14&P.
M870A1 Semitrailer Characteristics
||42 ft 6 in (13.0m)
||8 ft 0 in (2.4m)
||6 ft 0.875 in (1.9m)
|Ground clearance (40-ton load)
||1 ft 5.625 in (0.4m)
||9.5 tons (8618kg)
||40 tons (36,287kg)
||49.5 tons (44,905kg)
||13 tires 10:00x15 14-ply, commercial highway tread
||S-cam, two-shoe, double anchor, interval expanding, air actuated
|Max speed empty
||55 mph (89kmh)
|Max speed 40-ton load
||40 mph (64kmh)
Table data from TM 5-2330-378-14&P
The full nomenclature for this trailer is Semitrailer, Lowbed: 40-ton Construction Equipment Transporter M870A1.
The M870A1 was assigned NSN 2330-01-224-9245.
The Operator's and maintenance manuals for the M870A1 include:
- TM 07862A/07862B-CD SEMI TRAILER, LOWBED
- TM 5-2330-378-14&P OPERATORíS, MAINTENANCE & PARTS MANUAL (M870/M870A1)
The M870 was manufactured by Shoals American Industries, Inc.