OK, so I went out and did the unthinkable today. I took a tape measure, a straight edge, and a level and measured the distance to the outside of the tires on my 39 Dodge truck sporting a Dakota frame.

The original Dakota was a 1992 standard cab, long box with a 3.9 5 speed. It had the steel 6 bolt wheels on it.

The 6 bolt rotors were swapped over to a new pair of 5 bolt rotors. New bearings and new brakes were added.

The wheels on the front of the truck are 15" x 7" steel slots with a 4" back spacing (measured from the wheel mounting surface to the outside of the tire mounting surface.)

The tires mounted on the wheels are 225 60 R 15, they are 4 year old Furtura tires with 30 lbs of pressure. The sidewalls of these tires bulge out about 1" from the wheel edge (I did not actually measure it).

Measurement was made with the tires on the ground, a 5.9 Magnum (360) and its auto trans (motor sits 4" behind the original V6 location), aluminum radiator, a grill and the hood, no fenders and no bumper, and still using the original V6 springs. The front suspension is not lowered, the rear has 2" lowering blocks between the axle and the springs.

A straight edge was set against the bulge of the tire (the widest point)in a horizontal plane. The level was stood up against the rear edge of the straight edge with the bubble centered in the sight glass. The tape measure was extended out and the end was set against the inner edge of the level, or the same position of the outer edge of the tire at its widest point, at ground level. On the other side of the truck, the straight edge was placed across the tire bulge, the level stood up at the rear of the straight edge with the bubble centered in the sight glass. The level marked the tape measure at 70 and 1/4". Just so we are clear, I repeated the measuring process at both the front and the rear of the tires. The 70 and 1/4" is the rear measurement. The truck has just had the rack and the outer tie rod ends replaced and the toe has not yet been set. The front measurement came in at 70 1/8" My tires are about an 1/8" toed in right now.

So to the widest point on the 225 60 r 15 tires mounted on 15 x 7" wheels with 4" back spacing, on a 92 Dakota with the 5 lug rotors is 70 1/4". The track width is usually measured at the center of the tire. If we assume the tire bulge is actually 1 inch wider then the wheel, that gives us 2", and then the tire should be centered on the 7" wheel, so 1/2 of the 7" on both sides gives us another 7", plus to 2 = 9" to subtract from the 70 1/4 = 61 1/4" track width. Hmmm!

It was raining today, maybe I will get the measurements off my coupe. It has a 90 Dakota frame that was an original 5 lug rotor truck and it has a pair of Dakota 15 x 6" wheels on the front with 225 75 r 15 tires. Gene