Stovebolt.com Forums The Shop Area Driveline 17" Wheels on a '49 3600?

Hi all, first post here after many late nights sifting through all the good info here! I just acquired a 1949 3600 and will be doing the 16" wheel upgrade that's been discussed many times on here. The truck has modern 15", nondescript modern rims and 235R15 polyester radials on it now.

Plan A is the simplest: buy a set of 16" x 6.5" .5" offset Dexstar rims from eTrailer: https://www.etrailer.com/Trailer-Tires-and-Wheels/Dexstar/AM20766.html#exp-productdetails=.questions and put on a set of either 215 or 235/85R16's on. This was the solution discussed in the 2015 thread here: https://www.stovebolt.com/ubbthreads/ubbthreads.php/topics/1158249/1.html

According to the Tire Calculator (https://tiresize.com/calculator/), with the 215 rubber, I'll get a diameter (30.4") almost exactly the same as the original bias ply on the optional 17" wheels that you could buy in 1949. With the 235 rubber I get an extra inch of diameter (31.7" actually).

The goal for me is to get a bit more highway speed. The 235's should improve my speed for the same RPMs by 9.9%, while the 215's improve it over the existing tires by 5.2%. This is all to just tide me over until I get around to doing a ring and pinion swap in the rear end (if I can find the parts).

So two questions:

1. Anybody have rubbing or fit issues with the 235's? Is the truck still steerable or is that too much rubber on the road? Carl52 advised in this current thread that 16x8 would be too much, but I get the sense that 16x6 with 235's is ok: https://www.stovebolt.com/ubbthread...-wheel-question-52-3100.html#Post1368033

2. Has anybody tried fitting 17" wheels on a 3600? With a tall radial that might be worth a fifth gear! :-)

Thanks for the help!
Pops

I have 17" artillery wheels on a 1/2 ton. Harder to steer for parallel parking and tight places but ride quality is excellent, radial tires, of course.

My '48 3/4-T had three 700x17's and one 750x17 (old bias ply) tires on it when I bought it.

Hey Cosmo, what diameter did you end up with running those artillery wheels? Do those things bolt right on or do they need modification?

17” wheels/tires were an option on 3600 trucks that year.

http://chevy.oldcarmanualproject.com/chevyresto/4996.htm

PapaD,

235 75R 17 = 30.88, I believe that is officially 'Poor Man's Overdrive' Territory.

Some diameters and a summary of wheel numbers I've read, both from here and elsewhere.

235/75 R15 = 28.9" Pretty close to the original wheel diameter on a 3600
235/85 R16 = 30.5" Almost exactly the same as the optional 17" wheels you could originally order
235/85 R17 = 31.7" Picks up an inch over the original 17" option, 3% better (lower engine speed for same MPH) than the 234/85 R16 and 13% better than the 235/75 R15

3 1/2" backspace is a must (if you want to avoid using spacers) according to the prior posts on this board, although some members indicate that 4" backspace might do if you have the 1 ton tie rod ends. It's close to impossible to find the 3 1/2" backspace (Dexstar trailer wheels are the popular recommendation: 16x6 8/6.5), so it would be nice if we could squeak by with 4" as well.

Bolt pattern spacing is 6.5" which is 165.1mm, not 160mm as is sometimes stated.

Lots of guys say that Ford rims work, but I've not had much luck confirming backspace just from websites selling them. Either the data is not listed or when it is the backspace for the listed rim is greater than 4".

Grigg posted on here about using 19-19.5" wheels. He was using bias ply truck tires, but if you could put a radial on those they would be a whopping 34.7" in diameter for a 235/85 R19. That would be awesome if you could fit all that under the fenders!

Will a 19" wheel completely clear the tie rod end on a 3600? The 16" rim looks like the tie rod is about 1" past the diameter of the rim or right at rim/tire interface. So a rim 3" greater in diameter might clear the tie rod end completely . . .