Lowering 1981 c20

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ajwic1

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Hi there, I have a 1981 c20 and im looking to lower it 4/6 or 5/5 in that ballpark. would i be correct in saying that a flip kit gets you 8 inches not 6?

I've really struggled to find kits and lowering parts for this truck tbh. Any advice on how to achieve my goal is welcomed.
 
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If you add it up, just look at your suspension now and add the thickness of the springs, the perch and the axle and that’s how much it will lower it. About 6-6.5”.
As far as lowering kits and parts, they are plentiful, anything you might need.
 
84GMCSierra

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ajwic1 said:
Hi there, I have a 1981 c20 and im looking to lower it 4/6 or 5/5 in that ballpark. would i be correct in saying that a flip kit gets you 8 inches not 6?

I've really struggled to find kits and lowering parts for this truck tbh. Any advice on how to achieve my goal is welcomed.
Click to expand...
If and when you lower your truck, please post pics. I want to do that with my 84 C2500, but not so low. Maybe just a couple inches.
 
mlsceo

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84GMCSierra said:
These guys only show 2020-2023 years for GMC. In Chevy, they only go back to 1988
Click to expand...

You're partly correct. They go to 88 for GMC. For Chevy they go back as far as 1970 for axle flip kits. For drop spindles etc, they go to 71. I had to look back at the OP's avatar again to notice that he's working on a c2500 not a c20. His post reads c20, his avatar reads c2500. Which is it? On the other hand, wouldn't a shackle or drop spring be the same for an 81 c20 and an 81 c2500? Does one use coil springs and the other leaf springs? Maybe some more knowledgeable members can weigh in on that.
 
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mlsceo

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84GMCSierra said:
If and when you lower your truck, please post pics. I want to do that with my 84 C2500, but not so low. Maybe just a couple inches.
Click to expand...
Chassis Tech Suspension on Ebay shows 2" drop springs and shackles to fit c20, c2500. I would contact them to confirm fit though.
 
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mlsceo

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ajwic1 said:
Hi there, I have a 1981 c20 and im looking to lower it 4/6 or 5/5 in that ballpark. would i be correct in saying that a flip kit gets you 8 inches not 6?

I've really struggled to find kits and lowering parts for this truck tbh. Any advice on how to achieve my goal is welcomed.
Click to expand...
Chassis Tech Suspension shows a 6/8 kit to fit your c2500. (the listing reads 6/6 AND 6/8??) Apparently there are two styles of calipers to deal with, bolt on or clip on. You'll want to check which ones you have, then contact them for fitment. They also show individual parts that will hopefully get you closer to the 5/5 you mentioned.
 
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tboltkc

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Switch has 3/4 and 6/8 for 73-91 C20 & C30. Is GMC different?
 
mlsceo

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That's what I was wondering. A quick phone call would answer that question, but that's up to the members working on GMCs.
 
IDtag

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I ended up buying a flip kit, said will get me about 7 to 8 but can use shackle extenders to get it back to 5 or 6. Not ideal but will see how low it actually ends up. In the middle of a house remodel and keeping the wife happy is more important than getting the truck done so the dually sits and waits.
 
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84GMCSierra said:
If and when you lower your truck, please post pics. I want to do that with my 84 C2500, but not so low. Maybe just a couple inches.
Click to expand...
Your truck will be easy,front drop spindles and rear shackles,it will even ride like it does now. Steering geometry and spring rate will be same as factory.
 
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