Aligning Your Model T 

By Don Mitchell

Originally published in Tin Lizzies of Albuquerque Enchantment Flyer Newsletters, 2009

Part 1 (Sept. 2009)  

If you haven’t ever checked the front end alignment of your T, you might think about doing it. I had checked and adjusted the toe-in on my ’27 Tudor some time ago, but hadn’t checked the caster or camber. The toe-in (the manual calls it gather) can be checked per paragraph 151 of Model T Service Manual (MTSM) and is easily adjustable. The other two alignments, caster and camber, can only be changed by bending the axle. 

When I checked the caster, per paragraphs 147 and 148 of the MTSM, I found that it was a little more than the specified 5.5 degrees, but probably OK. Later I checked the camber and was very surprised to find out how far it was off. According to the paragraph 153 of the MTSM, the horizontal distance between the top and bottom of the felloe should be 1.5”. On my car the measurement on the left side was 3/8”. The right side was better, but still only 7/8”, 5/8” less than it should have been. Measuring the camber per the MTSM is not feasible. Figure 122 shows the distances that need to be measured between the top and bottom of the felloes. Unfortunately, the line between the top of the felloes goes through the engine.  However, the measurements can be made on the outside of the wheel so the problem is easily overcome. I made a simple fixture to make the measurements and would be glad to share that information. 

Once you’ve made the measurements and found that the camber and/or caster need to be adjusted the question is: How can I do that? The good news is there is an alignment shop in Albuquerque that can bend the axle without removing it from the car. It’s a place called Chets Wheel Alignment that has been in Albuquerque for many years and is located at 7815 Menaul NE. Their phone number is 299-4221 and the guy I worked with is Tim Ellis. He is friendly, knowledgeable, and even knows something about how to drive a Model T! 

When I took my car to him, he checked the alignment with his equipment. He found the caster to be 5.8 degrees, close to the specified value. He bent the axle so the camber was 2.0 deg on one wheel and 2.3 deg on the other. How we decided on that value is another story, but I later calculated that the camber, based on the MTSM specification, is 2.2 deg. 

Part 2 (Oct. 2009) 

In the last newsletter, I shared some ideas about checking the alignment on your T. I discussed the caster and camber measurements I made on my car and how they compared with the Model T Service Manual (MTSM). I promised to tell you this month how you can calculate the camber angle of your axle based on the measurements you make on the front wheels, but I decided that some additional information on how you make all of the alignment measurements would be more appropriate, especially if you who don’t have a Model T Service Manual. (It costs $24 and is well worth it.) 

The toe-in (gather) measurement is fairly easy to make and you can adjust it yourself, if necessary. The toe-in is the difference in the distance between the felloes behind and in front of the axle. Start by making sure the wheels pointing are straight ahead, and then mark two reference points on the rim which are the same height above the floor as the center of the hub. Then measure the distance between the wheel felloes at the front and rear reference points. Per Clarence, a good way to do this is by clamping two yardsticks together and adjusting them until they are just touching the felloes or rim. You then measure the length of the yardsticks to find the distance. The difference between the front and rear measurements is the toe-in. Per the MTSM, the difference should be 3/16” to 1/4”, with the front distance being smaller than the rear. This is important since a Model T with the wheels toed out (rear distance less than front) will not steer properly. In Part 3, I’ll explain how the toe-in is adjusted. The second measurement, caster, is the amount the front axle spindle is inclined (pitched) toward the rear of the car. Figure 119 in the MTSM shows you how to measure it. Make sure the front wheels are on a level surface, place a square on it (or on blocks resting on the surface) against the lower spindle bushing, and then measure the distance between the upper leg of the square and the upper spindle bushing. Per the MTSM, the distance should be between 1/4” and 5/16”. If it is, this means the caster angle is close to the required 5.5o. If is very far off, the axle has to be twisted to achieve the proper caster. This is not easy to do; however, Tim at Chet’s Wheel Alignment (see Part 1) can measure the caster (in degrees) and thinks he might be able to twist the axle, if necessary, to correct it. In extreme cases, the axle might have to be replaced. 

The final alignment measurement is the camber which, as your looking at the front of the car, is the amount the top of the wheel is tilted out compared to the bottom. To check the camber, you need to determine the distances between the top and bottom of the felloes (Fig. 122 MTSM). You can’t do this directly, but an equivalent measurement can be made using a simple fixture, consisting of the following pieces of a straight wood: a 3/4” or thicker board about 6” x 6” square, a 2x4 about 28” long, and two 3/8” x 8” dowels or strips of wood about the same thickness. Make sure the end of the 2x4 is square and then attach the board to the end with wood screws so it forms a firm base to support the 2x4. You will also need two clamps to hold the dowels or wood strips on the 2x4 when you make the measurements. The wheels also need to be on a level surface.

In Part 3, I’ll tell you how to make the measurements, check them against the MTSM specification, and express the camber in degrees, which is what alignment shops understand.

Stand by for the next installment!