[KIILew]

The components provided in the Z82 Trailering Special package varied by model and model year, but to echo Chris, on your friend’s 1978 C20 the option included the UA1 heavy duty battery and N41 power steering, and the Trailering Special emblem. The purchase of the option also stipulated that the V01 heavy duty radiator be installed at a cost beyond the Trailering Special option cost if the sm465 transmission was chosen and air conditioning was not. This stipulation did not apply if the buyer selected either the automatic transmission or air conditioning since the heavy duty radiator was already included with those items.

At any rate, in the case of the ’78 C20, the package could be purchased with the 350/350 and 454/400 V8/automatic transmission drivetrains, or with the 350 or 454 engines teamed with the sm465 manual. Axle ratios included the 3.73, 4.10 and even the 3.21 – the latter which was exclusively available with the 454 engine. The particular engine/transmission/axle combination determined the gross combination weight rating of the vehicle/trailer combination, and this GCWR number was printed just below the “Trailering Special” script on the emblem.

On the C20, the Z82 Trailering Special package did not require the heavy duty springs, tires, and brakes that the more popular Z81 and Z83 “Camper Special” option packages included since trailer towing placed fewer demands on these components than carrying a cabover camper. As a result, the “Trailering Special” could be equipped with any of the four GVW rating packages (not to be confused with the above-mentioned GCWR) available on the C20 (6,400, 7,100, 7,500, or 8,200 lbs. GVWR). However, GM issued a special set of guidelines for 5th wheel trailer usage, which mandated that the 7,500 package be selected as a minimum for such an application (with upgrade to the maximum 8,200 package as an alternative). For this reason, the 7,500 lb. suspension package is found on most pre-1980 Trailering Special C20’s (this is my own personal observation).

Interestingly, in the early years (i.e. the 1973-1979 time frame) the Z82 option typically did not include a receiver hitch, trailer wiring harness, or even an engine oil cooler. Those items were usually available as separate options, however, and eventually became incorporated into the trailering package during the 1980’s. Locking differentials, while not a part of the package during 1973-1987, were recommended by GM as a supplement to the Z82 package for trailer towing, and as such are often found on Trailering Special – equipped trucks.

As far as rarity goes, I do not know the production stats for Trailering Specials. However, I do know that the Z82 package was introduced to GM pickups, vans, and sport utilities during the 1973 model year, and it continues to be offered to the current day. Personal observation make me conclude that the Trailering Special option was very, very rarely seen on 1973 and 1974 models, only slightly more evident on 1975 vehicles, and somewhat more common on 1976 – 1980 vehicles, although it never reached the commonality of Camper Special –optioned 20 and 30 series trucks during those years. During the 1980’s Trailering Special production took off, and today trailer special optioning is selected on the majority of pickups, suburbans, tahoes, etc.

Hope some of this info is useful…

Ken Lewis