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A BRIEF HISTORY (copy from a friend in UK, Mutt Gurus Kens Mutt Page
The M151 was designed by Ford Motor Co. with guidance from the US Army's Ordnance Truck Automotive Command (OTAC) and development work began in 1951. Various types of experimental and pilot vehicles were developed and evaluated, including separate chassis/body combinations, aluminium vehicles, solid-axle versions etc. but the final version accepted by OTAC was an integral chassis/body (monocoque) unit, with all-round independent suspension, 24-volt waterproofed electrical system, two/four-wheel drive, with a four-speed, single transfer transmission. First gear and reverse were sufficiently low-geared to equate to the low-transfer equivalents found on the MB/GPW, M38 and M38A1 predecessors. The first contract was awarded to Ford and vehicles were issued to the Military in 1960 (Model M151).
In 1963/64, a revised version of the truck was designed, and was designated the M151A1. It featured a heavier-duty rear suspension, designed to cope with add-on weapons and extra loads, which had caused problems for the suspension of the basic M151. Delivery commenced in 1964 and continued up to 1969, with vehicles being built by both Ford and Willys (later Kaiser). The M151A1 was also adapted to carry the recoilless rifle (designated M151A1C) and an extended-bodied version was used as a front-line ambulance (designated M718).
The independent rear suspension configuration of the M151 and -A1 models gave rise to an oversteer condition and this, together with a lack of body "tilt" on cornering, led to many accidents, where the vehicle abruptly went out of control and/or rolled over when sudden steering movements were made. Despite training courses, films, circulars and pamphlets, the vehicle gained a reputation as being unstable, and efforts were made to "design out" the handling problems. At one stage, a MUTT was modified by having a rigid rear axle fitted (as per the wartime MB/GPW) but the experiment proved unsuccessful.
A redesign of the rear suspension was ordered and eventually the independent "A"-frame suspension was changed to a semi-trailing arm setup. This gave the handling characteristics of a solid-axle vehicle, while maintaining the flexibility of independent wheel suspension and retaining maximum parts interchangeability. This revised truck was designated the M151A2. This new suspension featured on all post-1969 versions of the vehicle, with the recoilless rifle version being designated M825 and the ambulance version designated M718A1.
Several new safety features were introduced, such as a deep-dish steering wheel, a one-piece windscreen with electric wipers and windscreen washers, plus bigger rear lights. Although handling characteristics were much improved, there were still rollover accidents. Even the fitting of Rollover Protection Kits (ROPS) to many trucks could not stave off the inevitable. The vehicle ceased production in 1982, when the advent of the "HUMMER"-series ended the MUTT era. Surprisingly, the M151A2 was still in US military service as late as 1997, when the US Marine Corps were seen to be using one during the unrest in Albania.
Suffice it to say that the M151-series has achieved a longer run of service than that of the MB/GPW, M38 and M38A1 series combined.
Because of the handling characteristics of the vehicle, the US Military decided in the late 1960's not to release any further vehicles to the public (although a few had, by this time, been disposed of at surplus sales) and all subsequent releases were designated for demilitarisation (by cutting, crushing or shredding) to preclude restoration as a usable vehicle. Despite the US Military's stance, other countries who had bought the M151-series disposed of their surplus vehicles without demilitarisation clauses. Most owners I have spoken to are well aware of the peculiarities of their vehicles' handling.
A trailer was designed for use with the M151-series, and was designated the M416. Essentially it was similar to the wartime MB-T / Bantam, and the Korean-War era M100 trailers, the notable differences being the shape of the mudguards (angular) and the wheels (same as the M151-series). In the early 1970's, an updated trailer, featuring hydraulic overrun brakes, was introduced and was designated the M416A1. These trailers, like the M151-series trucks, have been almost completely phased out of the US Military inventory.
M151-series trucks occasionally appear for sale in the U.K. and Europe but potential buyers should familiarise themselves with the chequered history of the M151-series before taking the plunge!
