3/4 ton suspension question

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Lance Fillspipe

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I have a question, I just picked up a 1983 GMC High Sierra K2500 and it rides very stiff. It came with a towing hitch and 5th wheel already on it. Not sure if the towing package was stock and if that's why the ride is so stiff but it was a 6.2 diesel that a previous owner converted to 350 sbc if that helps.
Its way more stiff than I expected, compared to the 1978 half ton 2wd Chevy I had back in high school. Is there a lift kit, suspension upgrades, and/or seat conversion you would recommend for better ride quality? Not sure my kidneys will be able to handle hunting season with the current set up hahaha. I'm new to the forum and new to the Square body 4WD scene. Thanks in advance for any and all info.
 

SDJunkMan

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Welcome. What part of South Dakota are you in? I'm in Rapid.

As for your suspension, we would have to see what you have. The previous owner may have beefed it up ( I am doing this to my plow truck), not sure what the factory offered for heavy duty suspension.

There are plenty of options availible as far as suspension goes.
 

73c20jim

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My 3/4 2WD rides like a truck. Oh wait it is a truck. 8200 lb springs, no modifications. I live on a dirt rode, 2 miles to get to pavement, and I really feel it.

Look at your ID plate to determine your weight capacity, which determines springs.
 

Blue Ox

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Tire pressures are an easy thing to check/set and can have a significant effect on ride quality.

And yes, a 3/4 ton is going to ride harder than a 1/2 ton. A 4WD with a beam axle is going to ride harder than a 2WD with independent suspension. Not quite sure what you were expecting.
 

Lance Fillspipe

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Basically, I'm just looking for suspension upgrades on ride quality. Went through a dip, that I've gone through hundreds of times with my 2012 GMC Sierra 1500 4WD, and was almost thrown through the roof in the 3/4 ton. lol. I didn't think the difference between 1/2 tons and this 3/4 ton would be night and day.
 

roundhouse

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I am installing new Alcan springs in my 1/2 ton this weekend

I will let you know how it rides

It has a 4” lift now and rides worse than most of the 18 wheelers I used to own

Also you can check to see if it’s the shocks

Unbolt one end of the shocks and zip tie it out of the way
And go for a test drive
 

Blue Ox

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Basically, I'm just looking for suspension upgrades on ride quality. Went through a dip, that I've gone through hundreds of times with my 2012 GMC Sierra 1500 4WD, and was almost thrown through the roof in the 3/4 ton. lol. I didn't think the difference between 1/2 tons and this 3/4 ton would be night and day.

Again, apples and oranges. Independent suspension vs a beam axle, plus a much lighter suspension in general. Check your tire pressures against the recommendations. It can make a significant difference if they're overinflated, but it's not going to fix that front leaf spring ride. The only way you're going to soften up the ride as significantly as you seem to want is to take leaves out of the springs.

Look at the data tag in the glove compartment and on the door, see if you can find the GVWR and any listing if it has a heavy duty suspension package. Then start counting leaves. We should be able to figure out if it's been added to, or if it's original.
 

CSFJ

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This probably rides really nice. Looks like it might even be all wheel drive too.

You must be registered for see images attach
 

73c20jim

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This probably rides really nice. Looks like it might even be all wheel drive too.

You must be registered for see images attach

What springs do I need for a 6" lift on it. Asking for a friend.
 

bucket

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So many variables here. It could have a bunch of leaves added in. It could have an old Rancho lift kit or similar. The springs could be shot and riding the bumpstops. Or it might just ride like any other stock 4x4 with 4 leaf springs and you just aren't used to it.

If you could get some pictures of your spring setup, it would be easier to give recommendations.
 

Dougnsalem

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It's probably a little late to use this now. Maybe next time....

I like to take a LONG test drive first, before I even think about buying a vehicle. Have a friend go with you, for a second opinion. For you non-mechanic types: take it to a shop for a prebuy inspection. Now, you could wind up dumping tons into it, when it all could have been avoided.
 

75gmck25

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The GVW rating should be on a tag inside the driver's side door frame. Mine is a 3/4 ton 4WD with 8200 GVW, which means 7 leaf springs in the back, rated for a 2600 lb load. Front springs are 4 leaf (I think). The ride is rough, but not that bad, and I'm using 10 ply rated tires at 60 psi in the rear.

You can always swap in 1/2 ton springs if your spring length is 52" (the most common). Some 1 tons had 56" springs, which may actually ride smoother, but you would have to move the mounts on your truck. My rear springs are rated at 2775 lbs /spring, but as low as 1875 lb rating was available on half ton.

Bruce
 

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