1991 6 Bolt C2500 bolt pattern?

[Dalaigh]

I just bought a 1991 C2500 LD, and I have been trying to find the factory offset. Does anyone know what it is? All I can find is that it's a low offset, which doesn't really help me, unless someone knows what that means number wise. I need a millimetre number so I can start looking for rims…

Anyway heres my truck with the rims in question…

[special-K]

The bolt pattern is the same as always on GMs...6 on 6.5". The back space I'm not sure of, but it's the FWD profile compared to the traditional RWD profile, which has a greater backspace. I'm sure someone can help you, but you can measure back space easily. Just pull a tire, lay straight edge on lip of wheel across the center on the back side, and measure to backside of wheel where stud holes are

[BigBlocksRule]

Can't you pull a stock one off and measure backspace or all 4 frozen to the ground in the great white north?

[YankeeHauler]

Special-K, I thought 8 Lug was 6.5". and 6 lug was 5.5"?

OP-http://www.wheel-size.com/size/chevrolet/2500-truck/1991/?PageSpeed=noscript

1500 Truck

Bolt pattern 6x139.7

Diameter: 15'' - 16'';
Width (inches): 7 - 7.5;
Offset (mm): 5.




Rims for Chevrolet 2500 truck 1991

Bolt pattern 8x165
Diameter: 16'';
Width (inches): 7 - 8;
Offset (mm): 12.

[Dalaigh]

I know the bolt pattern is 6x6.5, they are the same as my 2014. But, it's too cold out right now to take the rim off and measure the back spacing. I was hoping someone would know, so I could figure out what I wanted to do for new rims, because I'm impatient and don't want to wait till it warms up…

[special-K]

Originally Posted by YankeeHauler

Special-K, I thought 8 Lug was 6.5". and 6 lug was 5.5"?

You're right. I mistyped and can't edit till I renew my membership

Originally Posted by Dalaigh

I know the bolt pattern is 6x6.5, they are the same as my 2014. But, it's too cold out right now to take the rim off and measure the back spacing. I was hoping someone would know, so I could figure out what I wanted to do for new rims, because I'm impatient and don't want to wait till it warms up…

The title does ask what the bolt pattern is. I'm not familiar with late models, is the 6-lug pattern still SAE? I'm pretty sure the 8-lugs are metric now and have been meaning to ask what year that started. I have the 8-lug factory steel wheels I can measure. I'd bet they have the same backspace, but I'm sure before long someone will pop up with the 6-lugs to measure

[Dalaigh]

Sorry I typed the original post after a long long day at work in the cold, didn't realize I had typed bolt pattern. Meant offset… Just like yesterday when I meant 6x5.5 not 6.5, long days outside in -11F weather makes you tired…

But last night I tried to do more searching online and ever site I come across says H,M or L as a backspacing on these old truck. I've come to find out that H is high (35mm or greater) M is medium (around 20mm offset) and L is low (typically 0mm and down).
And some sites have said that my rims are L, so I'm around 0mm… It's suppose to warm up next week so I'll have to take off a wheel and measure the backspacing, then I can get the offset…

[b454rat]

I always get offset confused. The wheels are 6" wide, and offset is like 5.5" to the inside, meaning most of the wheel is tucked to the inside. I think the wheels are the same as a 4wd, but never owned one like yours. If your looking for aftermarket wheels, I'd think ones for a 4wd will work. I know the 15" rally's off the squares won't fit, they hit the caliper or ball joint, can't remember...