Stock wheel size of 3/4th Ton Pre-80

[78Scottsdale]

I'm really digging for information, Trucks are alot more complex than Old G Bodys i've found out.

Anyways, I thought the wheels that came on 3/4th ton trucks Pre-80 were all 15 inch, but after talking to a guy that owns a different site dedicated to these years of trucks he said they came with 16.5 inch rims and If I were to fit a 16 I would have to trim the calipers.  I have no problem going with a 17 inch rim (If I have to).  Is there anyone here with a 77-79 K20 that knows for a fact what the wheel size is, not that I don't trust this man (Chuck) but Im wondering if these trucks may have came from the factory with 15 inch rims? He says any 8 lug rim will fit over a full floating axle as well.  I don't have the money to be buying something that may not fit, So I really need accurate information from guys like you all who have seen it all.

Thanks

[Flamingbig10]

73-87 3/4 tons came with 16s and 16 .5 wheels

[Reinovator]

Hi,
  I have a 80 one ton with 16" and had a  78 and a 77 3/4 with 16"  I drove a 76 with 16.5s. the 16.5"ers were usually early 70's although I have ran into fleet trucks with 16.5s.
 The best way to find out what yours had stock is the glove box tag or if you have the original door and or door jam  the tags there will help.
good luck have fun

[79K20]

16s and 16.5s were both available. Both will fit fine.

From what I have seen, you cannot clear a set of 15's because of the clearance to the front calipers and the rear drums (on the 14FF axle... I'm not sure about the 14SF axle)

[78Scottsdale]

16s and 16.5s were both available. Both will fit fine.

From what I have seen, you cannot clear a set of 15's because of the clearance to the front calipers and the rear drums (on the 14FF axle... I'm not sure about the 14SF axle)

Thank you very much.

[farmallgray]

My 79 K-20 had 16" originally. I have heard that 15s will fit if you grind the calipers for clearence. I haven't done it myself though.
I know they will clear the LD 11" rear drums on a 14 bolt FF, but I don't know if they clear the HD 13" drums.

[78 Chevyrado]

From what I can tell the 16's were the skinny wheels and the 16.5's were the wide wheels.  Skinny's are like 5 inches wide and the wides were 8 inches wide.

[78Scottsdale]

I read the tire it said 16.5x8.75

I'm stuck inbetween buying tires for a 16.5 inch rim, or buying 16-17 inch rims and buying a tire for that.

The thing is I don't really want stock white steel wheels on my truck..

But I don't have alot of money.. But I could paint the rims black as well..

[78 Chevyrado]

I'd get 17's  theres lots of choices for them.  a lot more than for 16's.  the most all terrain choices are in 15's and 17's.

[olblue2]

thats what im running into now, my 1977 k-20 4x4 has 16.5 wheels on it.  but it has aftermarket aluminum modulars with 35x12.50r 16.5 bfg mud terrains.  i wanna go to a lil wider tire but dang not many tires out there in a 16.5 rim size