Dually Wheel Fitment Help
- Thread starter Android04
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Salty Crusty
Full Access Member
- Joined
- Apr 10, 2020
- Posts
- 211
- Reaction score
- 231
- Location
- Texas
- First Name
- Gary
- Truck Year
- 1986
- Truck Model
- c1500
- Engine Size
- 565
Have you checked into a simple hub swap? Axle tubes are all the same length, it's the hubs that make the difference. Check out the 14-bolt Bible at the Pirate offroad website, they have a ton of info on 'em.
OldBlueDually
Full Access Member
- Joined
- Jun 8, 2020
- Posts
- 2,428
- Reaction score
- 8,518
- Location
- Minnesota
- First Name
- Justin
- Truck Year
- 1976 GMC
- Truck Model
- C30
- Engine Size
- 455 Olds
Hey gents, so what you are basically summing up is the 14-bolt corporate rearend is the one that would work well in the OP's truck for a bit of fender clearance?
I saw @Android04 original post in this thread and thought "oh $h!t, are you fugging kidding me"......granted my ride does not have what his has, but this was one more thing that I would be concerned about now as I have NOT put on my outer dual's yet with her lowered.
@Android04 your truck is beautiful, I just love those rims you put on there. Good choice of color too!
@Big Chip I wonder if you could spell it differently, like dooshbag and get away with it?
--well look at that, you sure can.
I saw @Android04 original post in this thread and thought "oh $h!t, are you fugging kidding me"......granted my ride does not have what his has, but this was one more thing that I would be concerned about now as I have NOT put on my outer dual's yet with her lowered.
@Android04 your truck is beautiful, I just love those rims you put on there. Good choice of color too!
@Big Chip I wonder if you could spell it differently, like dooshbag and get away with it?
--well look at that, you sure can.
fman88
Junior Member
- Joined
- Oct 5, 2022
- Posts
- 1
- Reaction score
- 2
- Location
- South San Francisco
- First Name
- Efrem
- Truck Year
- 1975
- Truck Model
- C30
- Engine Size
- LS3
Hopefully I can add value to this string. I'm lowering my 75 C30 2wd single cab as we speak. Yes by just bolting on a set of 22 inch dually direct bolt on wheels from JK Motorsport the wheels will stick out past the fenders. At least an inch or more. Barf..
Some history on the wheels. All 6 wheels are the same size 22 x 8.25 They are traditional in a sense that the wheels could be used in any position of the truck (front, rear inner and outer). But JK was cleaver and machined each wheel so they are specific for each position. I believe the wheels start out as blanks that they machine for the proper 8 lug bolt pattern (chevy, ford, dodge, 8 x 6.5, 8 x 210....) But the center bore is made to fit all style axles so it cannot be hub centric to center the wheel onto the axle which is critical in having a smooth ride. So JK tapers the lug holes to use a achorn style lug nuts to center the wheel on the axles. They taper the lug hole for the front wheel and polish the outer surface. For the rear outer they do the same but cut the taper and polish the wheel on the inside. For the inner they do nothing to the lug nut hole and leave both sides plain. That wheel is basically squished in between the hub of the axle and the outer wheel. The problem there is that the wheel cannot be centered because the center bore is bigger then the hub and you cannot put a taper in the lug hole for a lug nut becasue you still have to put the outer wheel on. Also the new wheels are so thick from JK Motorsport there is not enough wheel stud to put a lugnut on. The wheel stud is flush with the wheel hole. We'll get back to this issue later with a fix down the road when we address the axle.
In order for me to run the wheels inside of the fenders I used a cab and chassis 14 bolt factory rearend. They are narrow as compared to a dually that has a pick up bed from the factory. The rearend is a direct bolt in. I then installed an 8" flip kit. No issue there. Next is to puchase a set of factory style widened inner fender wells. I believe they are 3" wider then stock and bolt into the stock location. You have to cut the bed to make room for the new wheels because they are wider then stock.
So here is the magic recipe that fixes all these issues. I had to make a special wheel adapter to 1. Space out the inner wheel from the leaf spring, 2. Center the inner wheel, 3. Have a longer wheel stud to accomodate the thicker wheel.
The aluminum adapter that was made is 1.50" thick, has a step machined into the base so it can sit right up aganist the hub (14 bolt has a little ridge at the base of the hub), has a bolt pattern of 8 x 6.5 to 8 x 6.5, was machined to fit a stock chevy dually wheel stud (Dorman # 610-194) and a steel ring pressed in and machined (.75" tall) on the outer adapter to center the inner wheel. The steel lip is only tall enough to center the inner wheel. Remember the outer wheel had a taper in the lug hole for the lug nut to center the wheel onto the axle. Be sure to put a smear of anti-seize on the inside of the adapter after you press in the new wheel studs in case you want to remove the adapter in the future.
Once the adapter and wheels were installed the moment of truth came when I lowered the truck. The wheels dropped right inside the wheel wells. I had about 1.5" clearance from the edge of the tire to the inside of the dually fender. Bingo baby!
Anyone interested contact me and I can provide more details and photos on the wheel adapter mfg, prices and other things to look out for. Cheers.
Some history on the wheels. All 6 wheels are the same size 22 x 8.25 They are traditional in a sense that the wheels could be used in any position of the truck (front, rear inner and outer). But JK was cleaver and machined each wheel so they are specific for each position. I believe the wheels start out as blanks that they machine for the proper 8 lug bolt pattern (chevy, ford, dodge, 8 x 6.5, 8 x 210....) But the center bore is made to fit all style axles so it cannot be hub centric to center the wheel onto the axle which is critical in having a smooth ride. So JK tapers the lug holes to use a achorn style lug nuts to center the wheel on the axles. They taper the lug hole for the front wheel and polish the outer surface. For the rear outer they do the same but cut the taper and polish the wheel on the inside. For the inner they do nothing to the lug nut hole and leave both sides plain. That wheel is basically squished in between the hub of the axle and the outer wheel. The problem there is that the wheel cannot be centered because the center bore is bigger then the hub and you cannot put a taper in the lug hole for a lug nut becasue you still have to put the outer wheel on. Also the new wheels are so thick from JK Motorsport there is not enough wheel stud to put a lugnut on. The wheel stud is flush with the wheel hole. We'll get back to this issue later with a fix down the road when we address the axle.
In order for me to run the wheels inside of the fenders I used a cab and chassis 14 bolt factory rearend. They are narrow as compared to a dually that has a pick up bed from the factory. The rearend is a direct bolt in. I then installed an 8" flip kit. No issue there. Next is to puchase a set of factory style widened inner fender wells. I believe they are 3" wider then stock and bolt into the stock location. You have to cut the bed to make room for the new wheels because they are wider then stock.
So here is the magic recipe that fixes all these issues. I had to make a special wheel adapter to 1. Space out the inner wheel from the leaf spring, 2. Center the inner wheel, 3. Have a longer wheel stud to accomodate the thicker wheel.
The aluminum adapter that was made is 1.50" thick, has a step machined into the base so it can sit right up aganist the hub (14 bolt has a little ridge at the base of the hub), has a bolt pattern of 8 x 6.5 to 8 x 6.5, was machined to fit a stock chevy dually wheel stud (Dorman # 610-194) and a steel ring pressed in and machined (.75" tall) on the outer adapter to center the inner wheel. The steel lip is only tall enough to center the inner wheel. Remember the outer wheel had a taper in the lug hole for the lug nut to center the wheel onto the axle. Be sure to put a smear of anti-seize on the inside of the adapter after you press in the new wheel studs in case you want to remove the adapter in the future.
Once the adapter and wheels were installed the moment of truth came when I lowered the truck. The wheels dropped right inside the wheel wells. I had about 1.5" clearance from the edge of the tire to the inside of the dually fender. Bingo baby!
Anyone interested contact me and I can provide more details and photos on the wheel adapter mfg, prices and other things to look out for. Cheers.
