From the day I bought it, my T has had a tendency to pull to the right and I've always thought it was mostly just the downhill effect of being the right side of a crowned road, but maybe, after three years, I'm finally done kidding myself. My spindles were recently rebushed and that didn't change anything, so my suspicion is that the problem lies elsewhere—maybe.
You'd think something like this would have been covered already, but I did a search and couldn't find much. Maybe somebody can steer me to the right thread (pun intended—what the hell).
Check toe-in, camber, and caster on both sides. Should be the same. It may be a bent front axle or different spindles. Anyway, check all the steering geometry. Different camber on the two sides is the likely cause. A framing square, flat level floor, and tape measure are all you need. A long level will help check camber if you are on a flat level surface. Stand back and look at the front wheels, sometimes errors can be seen. A different axle may be the easiest way to fix the problem. But check first.
You're correct, the normal crown in the road will make it pull to the right. Does it still pull to the right if you drive on the left side of the road?
Other then the road slope check the wheel bearings, tires, tire pressure, caster and camber.
Check your toe-in, its the one characteristic that is easily changed.
Maybe it's crabbing. Check for equal distance from front axle to rear on each side.
Here's my input on this: Nearly every Engine pan I have ever had for a T (3/4) have had that wishbone piece that holds the front axle solid bent to hell sideways. I'm talking the "V" shaped metal piece that runs from the front axle to just in front of the transmission of the engine and sits in there with the ball on the end. I have been told that this can cause pull on the axle: maybe this is your problem? It would certainly be hard to see. Try taking a ruler and flashlight under your T and see if it's bent.
Side note: I had this problem with the engine i'm rebuilding: also it was dented in too. DO NOT heat it if you want to try and hammer it straight again. I did, and it warped the rivet piece so I need to send my pan off to be reworked by a metal smith I know. So far that's been my biggest Nooby mess up.
I wasn't clear on part of that. The "V" part is not bent, but the retainer that the ball of it sits in on the engine.
Caster will make it pull to one side.
Too much positive caster on the left side will make it pull to the right. Axle twist.
Do the thing with the framing square to see.
On rare instances a tire has also caused a pull.
All of the above could cause the problem as well as the chassis frame could be out of square. Also check that the front and rear springs are centered in the crossmembers. There is a hole in each crossmember for the through bolt at the center of the spring. The head of that bolt should be in that hole and the u bolts should be tightened evenly so that the body of the car does not lean down on one side or the other.
Check for your pull on a level surface such as a parking lot, or if you can find a road without much traffic, try driving right in the middle of the road so the crown is equal on each side.