Well known 8th USAAF historian and mv enthusiast, Steve A. Carr, has many of the answers in this four part series of articles that jeep owners have always wanted to know.
At a quick glance, the Willys MB and Hotchkiss M201 look very similar, more alike than the Ford GPW. M201’s were built from the same drawings and tools as the MB, so of course there is a close similarity, but over the life of the assembly line, small visual changes were introduced in addition to those which cannot easily be seen. Not all the changes were made from the beginning of the production run, and many jeeps were upgraded when they returned to the factory for rebuild. The more outward changes are listed below in no particular order.
| Hotchkiss M201 | Willys MB | |
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The Hotchkiss chassis number is stamped on the top of the left chassis rail, just ahead of the front axel. The French Army chassis number is the one stamped on the top right chassis member. It places the vehicle exactly in the manufacturing order. The Willys chassis number is a tag of the left frame member. |  |
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The chassis number ( above ) is different from the frame number which is shown to the left, stamped on the side of the right frame. This number is just a unique identity given to the frame when it was made. Frames weren’t used in order and so it cannot be used to identify age. M201 chassis were also made from a slightly thicker gauge steel than the MB’s. | |
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The body tub number was in different locations. On the M201 it was just above the fuel filter, but on the MB, it was stamped onto the front edge of the toe board gusset. |  |
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M201’s later had a ‘U’ channel welded into the front chassis leg as a reinforcing piece and also the radiator bracket was welded to the chassis. Neither of these changes were seen on the original MB’s. |  |
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The French data plate was one piece, and of course, written in French. The smaller red plate was the ERGM rebuild plate fitted when the vehicle returned to the factory for a major rework. |  |
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Metric instruments were also fitted to French jeeps. The kph Speedo also features a reset button. |  |
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The Hotchkiss grill while initially looking identical to the MB, actually has a shallower depth of pressings ( 1/4 inch ) around the curves top and bottom. The Willys is about 1/2 inch deep. |
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The hinge on the hood of the 201 is also made from 13 segments, as opposed to the 9 segments of the MB hinge. |  |
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A small and simple difference on the 201 was the use of Yellow headlight bulbs. |  |
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On the Willys MB, there is a small rectangle notch in the top of the instrument panel, where the fairing folds over the panel. There is no notch on the 201 panel. |  |