Original tires?
 

Does anyone have information on what kind of tires originally came on a 1975 C20? Brand, size, etc.

Re: Original tires?
 

Truck has original 16" rims I should mention

Re: Original tires?
 

Keith Seymore will know better then anyone else.

Re: Original tires?
 

7.50 x 16. Everybody switched to 235/85r16 radials shortly afterward

Re: Original tires?
 

Pretty sure only Ks came 16.5 rims and the C series was 15s.

If a C came with 16.5 I would say that was an option. Is your SPID intact? That will tell you your tire size.

Re: Original tires?
 

C20s and K20s could all be had with 16.5, it was stock for both. 16s were an option for a long time. Then 16s became stock at some point, don't know year, but I believe it was after 75. 15s were standard on C/K10 only - never on 3/4 ton trucks. 15s had 5 (71 and up C10) or 6 lug pattern (all K5/10).

Re: Original tires?
 

According to the GM Heritage Center the standard tire was 8.75-16.5 with 9.50-16.5, 10.00-16.5 (not available on Stepsides) and 7.50-16's available as optional equipment.

Re: Original tires?
 

Brands were the usual suspects: Goodyear, Firestone, Uniroyal. Whatever was cheapest at the moment.

Tires are usually high on the list for cost reduction, because whatever savings you can net per tire you can multiply by 5 (usually, or 4 with no spare tire)*.

K

* or 6 or 7 for dual wheeled vehicles.

Re: Original tires?
 

On a 1/74 C20 truck I bought today, it came with 7.50 / 16 C tube hwy tread tires...