Difference between HD and non HD front suspension 82 C-20

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.

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
I discovered tonight both upper control arms are history on my 82 C-20.
Looking for new parts, they specify HD and non HD suspension, but I am not sure how to tell the difference.
Can somebody please clue me in ?
Thanks !!
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,875
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I discovered tonight both upper control arms are history on my 82 C-20.
Looking for new parts, they specify HD and non HD suspension, but I am not sure how to tell the difference.
Can somebody please clue me in ?
Thanks !!
SPID
HD suspension depending on front or back im pretty sure means thicker frame. 6CP or something is for at least 4x4.. not sure about half ton.
You must be registered for see images attach

"For 1980 through 1986, the same models as those for '79 used cats. However, a new C6P heavy duty option was offered for C/K 20/25 models which provided an 8,600 lb suspension package. These new, heavier 3/4 tons cleared the 8,500 lb limit, and so did not use converters during this time period, nor did C/K 30/35's."

if your truck is over 8600 gvw truck, heavy 3/4 ton with a slightly thicker frame, heavier springs in the back, no cats factory, your truck would have less emissions components most likely but other than cat im not sure tbh, your brakes would be larger and or "HD" presumably for bigger loads, you would probably have a larger or bigger spindle or something.


Basically what your trucks SPID sheet say, what your door stickers say? Or plate if it still had that in 82.
 

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
The sticker is mostly disintegrated and not readable.
No emissions on the truck.
The rear brakes are the big 13" drums and I think the front disc brakes are JB-7.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,875
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I discovered tonight both upper control arms are history on my 82 C-20.
Looking for new parts, they specify HD and non HD suspension, but I am not sure how to tell the difference.
Can somebody please clue me in ?
Thanks !!
You must be registered for see images attach
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,875
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
The sticker is mostly disintegrated and not readable.
No emissions on the truck.
The rear brakes are the big 13" drums and I think the front disc brakes are JB-7.
if you have a sway bar and larger shocks, larger brakes, you prob have c6p
also looks like 4.10 rear not a 3.42
a 4 speed on the floor
wider wheels than the regular c20
 

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
Looking online at many sources, and am not finding any listings for HD control arms.
Some sellers specify WITHOUT HD suspension, so now i am stressed.
If I can't find what I need, the truck is history and going away one way or another.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,875
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Looking online at many sources, and am not finding any listings for HD control arms.
Some sellers specify WITHOUT HD suspension, so now i am stressed.
If I can't find what I need, the truck is history and going away one way or another.
i mean, I would suspect the heavier spring maybe requires something special possibly, i remember hearing about what defines a c30 vs a c20 control arm once, the construction I believe it was, the heavier ones being HD for c30, maybe its like that. possibly something to do with pressed in ball joint(I think the ydo that)
You must be registered for see images attach

82 c20

heres a 82 c30
You must be registered for see images attach
 

Blackbeard44

Full Access Member
Joined
Jun 14, 2020
Posts
280
Reaction score
258
Location
Washington State
First Name
andy
Truck Year
1985
Truck Model
K20
Engine Size
6.0 LS
what exactly do you mean by upper control arms are history, are the bushings shot, balljoints clunking, or have they vanished into the abyss?

edited for more content: If bushings/balljoints are whats needing addressed I would just change the worn parts and try to keep the original control arms, anything bought these days is more than likely made out of chineseium
 

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
what exactly do you mean by upper control arms are history, are the bushings shot, balljoints clunking, or have they vanished into the abyss?
The threads on the shafts are worn away, the threads on the arms where the bushings go are worn away, and the threads on the bushings are worn away, and the bushings are falling out.
No wonder the truck clunks at low speed when I turn the steering, and the truck developed a pull to the right when driving.
 

Blackbeard44

Full Access Member
Joined
Jun 14, 2020
Posts
280
Reaction score
258
Location
Washington State
First Name
andy
Truck Year
1985
Truck Model
K20
Engine Size
6.0 LS
Its weird that the delco parts page you posted says "heavy duty design" but doesnt specify if they are spec'd for a heavy duty suspension truck.
 

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
NONE of the sources I have looked at specify for HD suspension.
Taylor posted that parts sheet, she is trying to be helpful.
 

Blackbeard44

Full Access Member
Joined
Jun 14, 2020
Posts
280
Reaction score
258
Location
Washington State
First Name
andy
Truck Year
1985
Truck Model
K20
Engine Size
6.0 LS
rock auto has some mention of HD, I was just fishing around there
 

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
what exactly do you mean by upper control arms are history, are the bushings shot, balljoints clunking, or have they vanished into the abyss?

edited for more content: If bushings/balljoints are whats needing addressed I would just change the worn parts and try to keep the original control arms, anything bought these days is more than likely made out of chineseium
I know they are from China nowdays, and there's nothing we can do about that.
And you missed part of my post, I stated the threads in the arms where the bushings go are worn away, so even buying shaft/bushing kits won't do me any good, I need those threads for the bushing.
I looked at rock auto too, found ONE side that listed the term HD.
But that doesn't do me any good, I need to do both sides, and I have to verify HD suspension.
 

Blackbeard44

Full Access Member
Joined
Jun 14, 2020
Posts
280
Reaction score
258
Location
Washington State
First Name
andy
Truck Year
1985
Truck Model
K20
Engine Size
6.0 LS
autozone mentions "heavy duty design"
 

Attachments

  • Screenshot_20220209-211824.png
    Screenshot_20220209-211824.png
    227.5 KB · Views: 71

mtnmankev

Full Access Member
Joined
Jun 10, 2014
Posts
1,623
Reaction score
3,293
Location
Ash Fork, Arizona
First Name
Kevin
Truck Year
1984, 1983
Truck Model
K10, C20
Engine Size
383 Stroker, 350
I don't like to deal with autozone, and if the arms are $165 plus tax each, I will scrap out the truck.
It's the truck in the avatar pic I have.
Shame a nice rust free truck goes away, but crap happens.
 
Top