Wanna slam that 63-98 C10/C1500? Lets talk about it!

[LocoLocal]

Wheels/Tires:

Unless your spending $1000-2000 per wheel don’t stress over backspacing options. All the off the shelf cast wheels that you can get for $13-1500 per set are going to fit and there is usually only one option for the backspace. What you need to worry about more is the overall height and width of the tire you want to run. On the front you need stay generally around a 245 or 255 max on the width and with a 4” or 5” front drop around a 27-28” overall height. This would be like a 245/40/20 or a 255/35/20. On 81+ trucks you are probably going to have rubbing issues on the inner edge of the front wheel well and it will be pretty bad with drops over 4”. Shorter overall height tires can help this but keep in mind small sidewalls contribute to a stiff/harsh ride. One way to gain a little clearance is to swap to 73-80 inners. This will nearly eliminate the rubbing on a 4” drop and will make a 5” drop behave more like a 4” with stock inners. The other option is a set of Mild Slosh Tubz that will give you plenty of clearance and you can run a little taller tire as well if you’d like.

79 C10, dropping 5/7. Looking at 15" rims (I did buy the tubular control arms based on your previous recommendations) - is 4.5" backspacing/0 offset on a 15x8 going to give me wheel clearance issues? As for tires, I am thinking 255/60s all around.

ETA: read some more threads and other forums. Seems like there could be issues, but only one way to tell...

There is a set of van rallys (15x6.5) for sale on facebook locally. Was really hoping for black wheels, so maybe I will have those blasted and powdercoated.

 

[bluex]

79 C10, dropping 5/7. Looking at 15" rims (I did buy the tubular control arms based on your previous recommendations) - is 4.5" backspacing/0 offset on a 15x8 going to give me wheel clearance issues? As for tires, I am thinking 255/60s all around.

ETA: read some more threads and other forums. Seems like there could be issues, but only one way to tell...

There is a set of van rallys (15x6.5) for sale on facebook locally. Was really hoping for black wheels, so maybe I will have those blasted and powdercoated.

With tubular arms you should be ok with a 15x8. At the most you might have to trim the lower portion of the ball joint cup if they left it long.

 

[LocoLocal]

With tubular arms you should be ok with a 15x8. At the most you might have to trim the lower portion of the ball joint cup if they left it long.

Thank you!

I will report back.

Appreciate all your help and willingness to share your knowledge.

 

[DoubleDingo]

...At the most you might have to trim the lower portion of the ball joint cup if they left it long.

My engineering brain cannot get on board with trimming the ball joint cup. Yeah, just the cup, but still. Glad I do my own work and only use parts that fit without alteration when it comes to vital suspension components. It is a whole new world out there.

 

[bluex]

My engineering brain cannot get on board with trimming the ball joint cup. Yeah, just the cup, but still. Glad I do my own work and only use parts that fit without alteration when it comes to vital suspension components. It is a whole new world out there.

It's just the bottom portion of the tubing they use to make it on that style arm. I'll see if I can find a picture. On some arms they go ahead an bevel it but for some reason on c10 arms they don't.

 

[bluex]

There is a discussion an pictures about what you can trim on the arms here:

Post in thread 'Clearance issues with lowering spindles and what you did about it…' https://www.gmsquarebody.com/thread...-and-what-you-did-about-it….39891/post-842426

 

[ChuckN]

My engineering brain cannot get on board with trimming the ball joint cup. Yeah, just the cup, but still. Glad I do my own work and only use parts that fit without alteration when it comes to vital suspension components. It is a whole new world out there.

I hear what you’re saying. When I had to trim my ball joint cups, I got the all clear from CPP to do so, and actually they clearance them from their factories for some applications. It’s my impression that they don’t provide the clearance from the factory because most guys like bigger than factory wheel diameters so they don’t worry too much about it. And by the way, thanks @bluex for chiming in. When I started typing this, the page hadn’t fully loaded apparently and your response didn’t appear.

To the OP @LocoLocal i can’t remember if I read it here or on another forum, but apparently the van 15x6.5 wheels don’t save any headaches since the loss in width is all on the outside of the wheel and none on the inside lip where the problem occurs. Maybe I read that from Bluex , can’t remember, haha. I do know there are 15x7 rallies out there that supposedly remedy the problem, but my impression is that they are harder to find than the 15x8 rallies.

 

[LocoLocal]

I hear what you’re saying. When I had to trim my ball joint cups, I got the all clear from CPP to do so, and actually they clearance them from their factories for some applications. It’s my impression that they don’t provide the clearance from the factory because most guys like bigger than factory wheel diameters so they don’t worry too much about it. And by the way, thanks @bluex for chiming in. When I started typing this, the page hadn’t fully loaded apparently and your response didn’t appear.

To the OP @LocoLocal i can’t remember if I read it here or on another forum, but apparently the van 15x6.5 wheels don’t save any headaches since the loss in width is all on the outside of the wheel and none on the inside lip where the problem occurs. Maybe I read that from Bluex , can’t remember, haha. I do know there are 15x7 rallies out there that supposedly remedy the problem, but my impression is that they are harder to find than the 15x8 rallies.

Shoot, thanks for the info. Looks like the 6.5s have the same backspace as the 8s. 7” wide has a 3.625 bs, so looks like you’re right. Back to looking at 20 inch wheels I guess…

Sorry to hijack the thread @bluex!

 

[Ricko1966]

Do you have a drill press and a 4 inch grinder or right angle grinder? I think I could rig up a fixture to hold a 4 inch grinder or right angle grinder inside the circumference of where the caliper slides are. Hang the spindle from the drill press chuck turn on the grinder and spin the chuck by hand. That will keep you center so your bearing isn't pushed to one side. If you had access to a lathe and a tool post grinder you'd be set but obviously you dont.