VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Tire Sizes and Options... What do the Numbers Mean

Tire Sizes and Options... What do the Numbers Mean ??

OK, In looking for tires for my 1930 Chevrolet AD Universal - Canopy Express Truck (Huckster) per the Manual the Tire size is 19" x 4.75". What excatly does this mean ?? I know that 19" is the Rim Diameter, but the 4.75" is that the tread width or Cross Section of the tire ??

I looked at the size on the tires that are currently on there, and they say this tire replaces 19"x 4.25", 4.75", 5.00", & 5.25". I measured the tires, the Approx Outside Diameter (Overall) is about 30.00" and the tread width is Approx 3.88" with the Cross section or Bulge Diameter Approx 4.50".

My question is wha tsize tires should I be looking for ??
When shopping around (COker for Example) I see sizes like 19x400, 19x450, etc... what sizes can I Use ?? can i use a larger cross section and tread width ?? Pros Cons, Thoughts ??

I used Coker Tire size 450/500-19 on my 1930 AD pu. They matched the 40 year old tires that were on the truck when I got it. The one thing I would highly recommend is the use of rim flaps between the rim and the tube. The split in the rim can wear a hole in the tube in a very short time. I didn't see any in Coker, but found some by using Google.

ArtM

Hello BearsFan315,
For an explanation of the old tire sizes, check out the FAQs on the www.millertire.com web site. Even though the discussion is aimed toward tractor tires and rims, it should answer your questions. I would guess that the 4.50 measurement is the bulge/cross section of the tire if I'm understanding correctly. Wider tires on your stock rims would round out the edges of the tread and not be efficient, I would think. Check out the drawings toward the bottom of the page also.