The '30X 3 1/2 Removal' thread had me looking up some other threads I'd saved for reference. Dad's TT had the old 'Factory' 10-ply 20" rear tires on 2 pc. rims (worm-drive Ruckstell), which were sidewall marked as "30X3 1/2". Now, I am a bit confused about 'What & why??' This previous thread kept for reference left me confused:
http://www.mtfca.com/discus/messages/506218/535023.html?1429413014
Lucy, can you 'splain' actual rim/tire size to me? Thanks.

Marv, I believe the truck tyres which fitted the 20" rims were marked 30 x 5". using the accepted formula, 30" minus twice the tyre height of 5" gets you to the 20" rim size. Might your memory of your Dad's TT be a little hazy?

Allan from down under.

There was 2 types of TT tires, I think I have 600-20's on mine.The older rims for 1918 or so are the 30x5's. I think those are the kelly springfield wheels?

-Allen-
I suspect you are correct. A photo of the old tire does show "30X5" markings. Shown. Still wondering about those 30X3.5 tires... Weren't they on 21" rims? Or were there changes in wheel/rim sizes? Mack, Dad's TT is a '26. Thanks.

The earlier tires were 32X4.5

Much easier to understand, as well as to know T's had 'many different-sized' wheels and tires through the years. (Take your tape measure along to the swap meets....) Thank you!

I was told the DeLong Brothers had a 25TT and also a 26TT. I never saw either only bit's and pices but up in the straw mow there was a new 32X6 also marked 600x20.

-Bud-
Using the simple 'old' formula would still reflect a 20" rim size...? ('BIG' tires!)

The 32 x 4.5 tires fit a 23 inch rim. 30 x 3.5 also fit a 23 inch rim. Only thing is, the 30 x 3.5 tire needs a clincher rim. The 32 x 4.5 is a straight sided tire. I've never tried it, but with no wire in the bead of a 30 x 3.5 clincher tire, I wouldn't think it would stay on the other type rim. I would think the pressure would force the tire outward until the tube could go out between the tire and rim.

Hal, there were 30 x 3.5" straight sided tyres as well as clinchers. Chevs had these between using 30x3.5" clinchers and then 21".

Allan from down under.

Found this in the 1923 dealer fact book...

(a guess would be they maybe changed tire size from time to time?)

-Hi, George-
Not to 'knit-pick', cuz "They are what they are." The drawing in this thread I'd saved says "123 inches" for the TT wheelbase (vs. '124' above.) Which is correct? Hap? Burger? Anyone? Thanks.
http://www.mtfca.com/discus/messages/506218/540527.html?1431436805
Marv

Marv,

I was curious to see if Bruce may have typo'd when he put the above spec in the 'cyclopedia...so...

I pulled out an original Fordex from 1923...

FWIW...Page 3 says one thing....page 34 shows something else...

Like all things Ford you will probably NEVER EVER get to that last pickle in the barrel no matter how long you hold your breath!!! But feel free to try...

(Were I to guess as to why...is that the true wheelbase is actually 123"+ a little bit and the marketing guys rounded it up while the guy who had the drawing crossed off the extra)

Thanks, guys! I believe the TT out in the shop measures in at a solid 123".
Perhaps the backing up/into the loading dock all those times 'compressed' from the 124"???