I'm sure it's an age old question, K 20 ride quality improvements.

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SirRobyn0

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Doesn’t really matter what load rating of tires are being used. Just adjust the pressure for the load or conditions or the ride quality.
Short of having med duty tires like 19.5s that have a rather high min pressure requirement, any LT tire (that designation is inclusive of all load ranges in the typical 16-20” rim sizes (and larger) can be aired down reasonably as seen fit for the load or ride.
Behind that, OP just needs new springs. The more expensive they are, the softer/better ride quality you can get.
And as mentioned above, the rear is upgradeable to newer longer OE springs which will help. And likely cheaper than high $ new aftermarket springs.
I agree that pressure plays a huge roll but higher load rater tires like D&E have more belts and much stiffer side walls even when deflated than an P. You are right that "LT" is inclusive of all LT ratings C,D&E. Back when I worked at cooper tire dealer in the 90's we sold truck tires and the only Cooper tire labeled as LT was the C rated tires, the D & E were label without LT markings. So I think of LT tires as only C rated in my head which is incorrect so I did not mean to be misleading.
 

Craig Nedrow

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My wife's 2500GMC rides rougher then my K20 with e rated tires. If you are not going to haul much weight, just take a leaf out, have done this with other trucks and it helps, Also if you are ambitious, pull each spring pak and radius the ends so they slide smoother, if the upper spring has wore a groove in the spring beneath, smooth that out. Could also use Teflon between the springs, slippery and helps the ride. Also grease the springs after smoothing them up with scotchbrite or something like that. The grease is an ol time fix from an....old timer. Flame on Garth!
 

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It is what it is. A few tips:
Forget cupholders, pushbutton radios and high speed passes over railroad tracks. Hopefully you'll never experience the pain of driving that button on the top of a ball cap into your skull on an unexpected speed hump. This is why men were tougher back in the day.
 

Backyard

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My 3/4 ton rides like a block of wood and steers like a wheelbarrow. I had half a mind to swap in half ton coils in the front and pull a few leafs or get halfton spring packs. It's just a cruiser anyways
 

SirRobyn0

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It is what it is. A few tips:
Forget cupholders, pushbutton radios and high speed passes over railroad tracks. Hopefully you'll never experience the pain of driving that button on the top of a ball cap into your skull on an unexpected speed hump. This is why men were tougher back in the day.
Sometime I'll have to tell you about getting my 88 Olds 88 airborne coming over some railroad tracks. Yes, the car lived, but she sure made some interesting noise on contact lol.
 

mrdap

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Rancho adjustable shocks.
RS9000XL series
With stock 3/4 ton springs it will make a world of difference.
 

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I agree that pressure plays a huge roll but higher load rater tires like D&E have more belts and much stiffer side walls even when deflated than an P. You are right that "LT" is inclusive of all LT ratings C,D&E. Back when I worked at cooper tire dealer in the 90's we sold truck tires and the only Cooper tire labeled as LT was the C rated tires, the D & E were label without LT markings. So I think of LT tires as only C rated in my head which is incorrect so I did not mean to be misleading.
Merry Christmas Rob!
And you’re correct on all accounts.
But I’ll still maintain you can get whatever ride out of LT tires you want.
Stiffer sidewalls imo are actually nicer for lowering pressure as you can make the tires as compliant as you want and maintain better tire shape when cornering. It’s all relative.
Just like pumping up P or XL tires above their max psi rating to reduce flex.
While I’d never recommend it publicly, I’ve done it many times on new half tons that still have the cheesy OE tires, when hauling heavy loads.
 

73cheyenne

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I got tired of the rough ride of my '73 K20 long ago. The front springs had almost no travel before the rubber bumpers hit the axle. I had the front springs re-arched at a spring shop to give more wheel travel. I removed some of the shorter leaves from the rear springs. I installed Firestone air bags with an onboard air compressor to regain load capacity when needed.
A few years ago I replaced the old bias ply tires, which they hardly make anymore, with new radials on 17" aluminum wheels. I don't run a lot of tire pressure unless needed. It all made a big difference. No more pogo stick ride. It's not a Cadillac, but it rides much better and is more comfortable. Too bad I hardly drive it anymore.
 
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SirRobyn0

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Merry Christmas Rob!
And you’re correct on all accounts.
But I’ll still maintain you can get whatever ride out of LT tires you want.
Stiffer sidewalls imo are actually nicer for lowering pressure as you can make the tires as compliant as you want and maintain better tire shape when cornering. It’s all relative.
Just like pumping up P or XL tires above their max psi rating to reduce flex.
While I’d never recommend it publicly, I’ve done it many times on new half tons that still have the cheesy OE tires, when hauling heavy loads.
Merry Christmas to you to!

I suppose it would come down to personal preference, and I do see your point. Honestly I have not experimented much. I haul loads so generally my E-rated tires stay at 50Ft and 70Rear, so I'm not constantly inflating and deflating.
 

pali7

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When I wuz younger, I had to have extreme stuff, 20-50 oil, heavy duty shocks, fast motorcycles and big chain saws. Now life is better. 5-30 oil, changed my 3/4 t C10 to 1/2 t, added airlift shocks and the best was installing KYB shocks. And I got a smaller chainsaw. It is pretty nice to ride in, but not as good as my Silverado with A/C. Happy New Year.
 

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Merry Christmas to you to!

I suppose it would come down to personal preference, and I do see your point. Honestly I have not experimented much. I haul loads so generally my E-rated tires stay at 50Ft and 70Rear, so I'm not constantly inflating and deflating.
For sure. I on the other hand have run a lot of HD pickups as commuter, soccermobile grocery getters. And alot of winter driving.
IMO that’s the beauty of heavy duty tires. Air em up for max capacity or down for comfort or traction.
Or anywhere in between.
Cheers!
 

Shorty81

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When I wuz younger, I had to have extreme stuff, 20-50 oil, heavy duty shocks, fast motorcycles and big chain saws. Now life is better. 5-30 oil, changed my 3/4 t C10 to 1/2 t, added airlift shocks and the best was installing KYB shocks. And I got a smaller chainsaw. It is pretty nice to ride in, but not as good as my Silverado with A/C. Happy New Year.
this is my 2nd biggest saw. I'm only 61, maybe when I get older I'll downsize...lol
 

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Safetyguy

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Original owner. Put on Rancho adjustable about 20 years back. No improvement. Still "Rides like a TRUCK!" Just turned 100k miles.
 

Safetyguy

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Had overloads on for a couple years. Those jarred your teeth. Tried a 4 x 8 one inch steel plate in the bed. Helped but didn't want to carry all that extra weight with the price of fuel and the MPG on these trucks. Sold the plate and the overloads. Replaced the front leafs as the original reverse arc ones were shot. Still rides the same but an inch or two higher in the front, helps with clearance on turns.
 

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