Ford Mustang/Capri 1979-1988 Repair Guide

Trailer Weight


Ford cautions that the 4-140 turbocharged engine should not be used for trailer towing, in order to prevent engine damage. Ford also recommends a minimum 6-cylinder engine and automatic transmission as the power train for towing Class l trailers of up to 1000 lbs. An external automatic transmission oil cooler is also recommended for any trailer towing other than the temporary, cross-town variety.

Trailer weight is the first, and most important, factor in determining whether or not your vehicle is suitable for towing the trailer you have in mind. The horsepower-to-weight ratio should be calculated. The basic standard is a ratio of 35:1. That is, 35 pounds of GVW for every unit of horsepower.

To calculate this ratio, multiply your engine's rated horsepower by 35, then subtract the weight of the vehicle, including passengers and luggage. The resulting figure is the ideal maximum trailer weight that you can tow. One point to consider: a numerically higher axle ratio can offset what appears to be a high trailer weight. If the weight of the trailer that you have in mind is somewhat higher than the weight you just calculated, you might consider changing your rear axle ratio to compensate.