1955 GMC Custom Stepside Pickup / Specs, Photos, Engines, Styling Details

Featured in this article is a great looking 1955 GMC Custom Stepside Pickup. The Stepside models have their rear wheel wells outside or the cargo box which results in a rectangular box without wheel well intrusion.

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1955 GMC 100 Stepside










GMC, a division of General Motors Corporation, produced some great styled light trucks during the mid to late 1950’s. At that time, the GMC trucks were considered by many to be the premium variant of Chevy trucks. As the years progressed the differences between Chevy and GMC trucks are very small.

During the 1950’s passenger car design influenced trucks to an even greater degree, and this included better mechanical performance, enhanced safety features and more comfort for passengers. The reasoning was that you could own a good looking pickup truck and utilize it for both work and pleasure.

Two GMC Pickup Series Comprised the 1955 GMC’s

The 1955 model year was a bit different for GMC. Two different models were produced  These were named the First Series and the Second Series.

The First Series GMC’s were essentially carryover designs from 1954. These early First Series models were the last of the GM Advanced Design styling which began in 1947.

The Second Series, coming out on March 25, 1955. was quite different since they were designed to compete against Ford’s newly designed 1953 Ford F-100. This mid production year debut of the Second Series  featured aggressive styling similar to that of the new Chevrolet passenger car models which were very modernized. This was not only GM’s most complete product change in the company’s history but likely its most successful as things turned out. Of styling significance for the GMC Second Series was a wraparound windshield and panoramic rear windows.

1955 gmc 100









The First Series GMC’s were built with the final GMC light trucks torque tube drive line, The GMC Second Series were produced with the more easily serviced open driveshaft.. The First Series’ six-volt electrical system was likewise replaced by the 12-volt electric system.

One big difference between the two 1955 Series involved the engines offered. When the Second Series trucks of GMC were introduced, they didn’t offer the small block Chevy V-8. Instead, the optional GMC V-8 came from Pontiac which was the 287 cubic inch V-8.

Power steering, a heavy-duty suspension configuration, chrome bumpers front and back and additional trim were options.

1955 GMC Half Ton Pickup Specifications

The base engine for both series of the 1955 GMC was a 243 cubic inch inline six that delivered 125 HP. The Second Series included Pontiac’s new 287 cubic inch V-8.

Standard transmission was a column mounted three-speed manual synchromesh. Optional was a four speed automatic.

Brakes are four wheel hydraulic drums.

Suspension included a semi-floating rear axle.

First Series had wheelbases of 116 and 125.25 inches respectively, while in the Second Series they had wheelbases of 114 and 123.25 inches.

Production estimates are that GMC produced about 83,000 light trucks for the 1955 model year. Another figure is that more than 13,000 were built in May, well after assembly of the First Series carryover models were halted on March 25.

Related Auto Museum Online articles are on the links below..

1957 GMC Half Ton Pickup

1972 GMC Suburban

55 gmc stepside









Reference material for this article includes..GM and GMC archive collection. For a good deal of additional GMC Truck information along with forums check out www.gmctruckclub.comGMC: The First 100 Years by John Gunnell.

(Article and photos copyright Auto Museum Online)

The GMC Pickup Collector Popularity

The First Series 1955 GMC’s are noteworthy since they were the first part of a model year where the truck’s styling was significantly changed in the middle of the production year. These First Series GMC light trucks represented the tail end of the Advance Design models which began in 1947. The last half of the 1955 model year ushered in the new Task Force Series.

The GMC 100 featured here is a Second Series model which was produced beginning March 25, 1955. Current sale prices for the models cover a wide range due to overall condition, restoration degree, originality and mileage. The range for good to excellent examples runs from about $40,000- $80,000.