86 K20 Front Leaf Springs

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viaminveniam1939

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Just replaced shocks and steering stabilizer. Observed, after I lowered the truck back to the ground, that the front leaf springs on my 86 k20 4x4 (former plow truck) are arched up slightly.

Is this proper or are they simply shot?

Thank U :)
 
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viaminveniam1939 said:
Just replaced shocks and steering stabilizer. Observed, after I lowered the truck back to the ground, that the front leaf springs on my 86 k20 4x4 (former plow truck) are arched up slightly.

Is this proper or are they simply shot?

Thank U :)
Click to expand...
That's normal.
 
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After I wrote this I realized I hadn’t been that clear. When I think of leaf springs, I typically think of rear leaf springs having a “big smile.” My fronts tho, have a slight frown.
 

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Frankenchevy

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viaminveniam1939 said:
After I wrote this I realized I hadn’t been that clear. When I think of leaf springs, I typically think of rear leaf springs having a “big smile.” My fronts tho, have a slight frown.
Click to expand...
Factory front springs are shaped that way. Although, those look to me to be aftermarket replacement springs. The individual leaves will typically have a beveled or rounded edge. Those look squared up, but it could just be the photo.

Anyway, inverted arc is the factory shape. Your plow will make the arc more pronounced.
 
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For reference, these are the factory original springs I removed from my 1-1/4ton CUCV. Notice how flat the front springs are? That’s why they invert once loaded.
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They are flat and those rear springs are beefier than mine. I suppose a cucv called for that tho? Different topic: How or will u or can u even address the speed limit rating of the cucv (65 or 75 is it)?
 
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The Army stenciled the CUCV fender with a max speed limit, but AFAIK this is only a driver safety limit set by the Army. With proper tires they are safe at normal highway speeds.

Blazer body CUCVs are relatively comfortable at normal highway speeds, but the high GVW pickups have a lower axle ratio (4.56?) and a 3 speed automatic, so they turn a much higher rpm at 65-70 mph.
 
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I didn’t this realize this!! Before I found my k20, I passed up on several low mile good condition CUCV’s out of fear / ignorance, that I would have to do some major swaps to not burn anything up.
 
bucket

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Frankenchevy said:
For reference, these are the factory original springs I removed from my 1-1/4ton CUCV. Notice how flat the front springs are? That’s why they invert once loaded.
You must be registered for see images attach
Click to expand...

Damn. Even your discarded parts are super clean, lol.
 
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75gmck25 said:
The Army stenciled the CUCV fender with a max speed limit, but AFAIK this is only a driver safety limit set by the Army. With proper tires they are safe at normal highway speeds.

Blazer body CUCVs are relatively comfortable at normal highway speeds, but the high GVW pickups have a lower axle ratio (4.56?) and a 3 speed automatic, so they turn a much higher rpm at 65-70 mph.
Click to expand...
The perfect combo for a nv4500 swap..uh huh yep
 
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viaminveniam1939 said:
They are flat and those rear springs are beefier than mine. I suppose a cucv called for that tho? Different topic: How or will u or can u even address the speed limit rating of the cucv (65 or 75 is it)?
Click to expand...
Gears, OD or gasoline engine swap. That diesel be screaming at 3500 rpm.
 
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bucket said:
Damn. Even your discarded parts are super clean, lol.
Click to expand...
To be fair, I disassembled them and cleaned them up before I swapped them for the ORD customs.

::cue @idahovette ’s standard response:: lol

viaminveniam1939 said:
They are flat and those rear springs are beefier than mine. I suppose a cucv called for that tho? Different topic: How or will u or can u even address the speed limit rating of the cucv (65 or 75 is it)?
Click to expand...
The rear springs made it ride like a buckboard. Didn’t come into its element until you had a yard of road base in the bed.

A 6.2 with 4.56 gears is a recipe for 60mph top speed. A gear swap or a gasser on some bigger tires will make a CUCV more freeway suitable.
 
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