Help on 8 lug conversion on my c1500

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So assuming you're doing a dually conversion to your 1500?

8 lug (whether 2500 or 3500) spindles don't directly bolt to 1500 control arms, upper ball joint is different. You could redrill the bolt pattern for the ball joint but since the 2500-3500 upper arms are better (forged) just swap to those. They bolt right onto the frame.

8 lug rear axle bolts right in as leaf spring width is same 1500-2500-3500 but what you have to decide is how you're going to solve the width issue. Semis won't fit between the dually fenders without changing something; some run a chassis cab rear because it's narrower but that will involve some other work as the width between spring packs is narrower, or some widen the dually fenders, etc. What kind of suspension setup you plan to run will come into play too, bagged, static, lifted, whatever.

Richard
So to put 8 lug front assembly on my c1500 I would have to Redroll the bolt holes ? I've got the 8 lug 14 bolt ready to go in. I want my front to be 8 as well.
 

someotherguy

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Just grab the forged uppers from the 8 lug truck. They bolt right in, as I said, and you won't have to battle with drilling out ball joint holes to run the correct ball joints to fit your spindle. Of course we're assuming a bit here as this is your first post and you didn't provide much detail.

Richard
 

L31MaxExpress

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Just grab the forged uppers from the 8 lug truck. They bolt right in, as I said, and you won't have to battle with drilling out ball joint holes to run the correct ball joints to fit your spindle. Of course we're assuming a bit here as this is your first post and you didn't provide much detail.

Richard
If he cannot find ones on a truck, the 96-02 van ones are the same too.
 
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Just grab the forged uppers from the 8 lug truck. They bolt right in, as I said, and you won't have to battle with drilling out ball joint holes to run the correct ball joints to fit your spindle. Of course we're assuming a bit here as this is your first post and you didn't provide much detail.

Richard
Yes sorry this is my first post. I just found out about this place.i have a c1500 6.0 4l80e with a 8 lug 14bolt rear end. I have yet to fund the drive shaft. And the front suspension. Just didn't want to have it Harder than it should be. All I want is my front to be 8 lug like my rear end swap Thanks and sorry for the late reply.
Just grab the forged uppers from the 8 lug truck. They bolt right in, as I said, and you won't have to battle with drilling out ball joint holes to run the correct ball joints to fit your spindle. Of course we're assuming a bit here as this is your first post and you didn't provide much detail.

Richard
 

dzynda

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Have you made any headway on your project?
Well I know you could go with the gmt800 spindle which will give you bigger better easier to change brakes then the obs style.
I've done this conversion on a few 1 ton duallies, 4wd but the wheel bearing hub is the same. When I do this I used the gmt400 1500 upper ball joint 6292 there are many brands which will have letters in front of the numbers depending on where you get them. I had to modify them to my gmt400 k3500 upper arms.
I'm curious about the 1500 gmt400 lower ball joints size, I can bring a spindle into my local auto parts store to see how it fits.
I'll check the tie rod ends too.
 

tpass

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The situation you're describing sounds a little nutty to me, but that's just my opinion. Have you considered how it's really going to look once you're done?

For the front wheels to sit right you need dually hubs, so get your front end parts from a 3500 dually. The hubs have large spacers to offset the crazy amount of backspacing a dually wheel has when used in the front position.

Click the link in my signature at look at my friend Tim's regular cab/stepside half ton that he converted to a dually, using a dually donor truck. Might give you a different path to consider.

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Richard
That is badass!
 

someotherguy

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That is badass!
My buddy Tim's truck and vision; parts from my salvage yard and where the bulk of the work happened. I pitched in here and there with ideas and work but it was Tim's baby. I liked that it used real 1 ton parts all over the place instead of faking it phantom dually style. Other than the frame being a 1500, essentially this was fairly close to a RCSB 3500. Obviously it wasn't built with the intention of doing 3500 work with it, but it did have 3500 suspension front and rear (minus some leafs), 3500 brakes, 3500 rear axle, and regular dually wheels. He kept the light duty 5 speed alive behind that big block longer than I thought it would last, but did eventually end up cracking the case on it.

Richard
 
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