Daughters ‘87 needs to ride smooth.

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squaredeal91

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Youre screwed, dude.
Best to buy coffee-colored carpet LMAO!
OMG HAHA that's really funny...

I thought the shocks I bought were pretty great. KYBs.

:signs8::happy175::idiot:
Just spilled a whole cup today on the front bench on the family burb!! Coffee happens
 

squaredeal91

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Could protect your seat like mom/Gma would do?? Lol
 

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YakkoWarner

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^Yup.
The tire pressure concept is lost on so many… even “car guys”. It’s sort of mind boggling.
I guess it’s the if “some” is good, “more” is better, so “max” (psi) just has to be bestest!
Worst part is the effin NHtSA is worse than your shade tree, dont know it all, person. They’ve mandated warnings if you don’t run way too much air pressure in some vehicles. IE newer 3/4ton trucks.
Although it is comical to see people who will beat the hell out of their spleens driving around an empty 3/4ton with 100-200% greater pressure in their tires than needed, “or the low tire light comes on.”

The tires also wear along the center line faster when inflated to max PSI on an empty bed. The back tires that were on my former F250 were like that - the guy had kept them at the or near the sidewall rating which would have been fine when carrying a load, but way too much for the empty bed. Lots of tread on both sides but the center was getting close to the wear bars. Trailer tires will often have the same issue if you don't adjust the pressure for the load (or lack of).

Running too soft can have its own issues though - especially in handling and cornering. I prefer a firmer tire on my cars because too soft can start to get a mushy feel and imprecise handling.
 

Bextreme04

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The tires also wear along the center line faster when inflated to max PSI on an empty bed. The back tires that were on my former F250 were like that - the guy had kept them at the or near the sidewall rating which would have been fine when carrying a load, but way too much for the empty bed. Lots of tread on both sides but the center was getting close to the wear bars. Trailer tires will often have the same issue if you don't adjust the pressure for the load (or lack of).

Running too soft can have its own issues though - especially in handling and cornering. I prefer a firmer tire on my cars because too soft can start to get a mushy feel and imprecise handling.
I have 35" E rated Falken Wildpeaks on my K25. They sit at ~28PSI most of the time. When I go put 3,000lbs of gravel or dirt in it I'll bump the pressure up to about 50PSI in the rear and 35 in the front and it rides just about the same as the lower pressure does unloaded. I have 63" K2500 suburban 5-leaf pack in the rear now and 4" lift Tuff Country EZ-Ride HD springs in the front with an ORD sway-bar disconnect. It doesn't ride quite as soft in the front as my C20 used to, but it's pretty close for the most part.
 

Hunter79764

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I'm a visual guy, here's a graph to illustrate the load rating and pressure relationship, and the idea of load range E or other higher load tires as well. The OE design is to take the loaded max axle weights, determine the corresponding pressure, then apply factors to account for how low tires are expected to get, how much extra capacity, etc., which means that you get 3/4T trucks jittering around the road and feeling every piece of gravel. Dropping pressure based on ACTUAL tire load gets the ride back to the way tire designers intend them, since we rarely run loaded at the max weights.

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Grit dog

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^And there’s load vs pressure charts for all tires. And all tires are rated the same for the same size. Even different load ratings. Only difference is lower load rating tires max out at lower pressures.
And load rating for a particular psi is a liner function of sidewall height and width.
IE the same width and diameter tires. The tire with the smaller rim/higher aspect ratio will have a greater load rating at the same pressure.
 

Bennyt

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Assuming the suspension is in good shape and doesn't require repairs...

I'd start by buying some Sulastic or velvet ride shackles. They will smooth out the ride immensely when running empty. One hour install.
 
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gogo14910

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FINAL ANSWER…
The sidewall max is 50psi. I wanted the tires to be properly inflated but 50 seemed too high so I got close. I just dropped all 4 tires from 45 to 35psi. What a difference! I think gas shocks are next? I’ll have her in a caddy in no time. First truck so she doesn’t have complaints. Thanks to you all, I’m glad she lets me drive sometimes.
 

HotWheelsBurban

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My one ton crew cab has E rated 245/75R16 tires, Michelin on the rear and BFG commercial T/As on the front. I run 45 in the front and 70 in the rear; I don't haul loads a lot but don't want to have to air up before loading. With a minimal load in back(~100-200#) it rides like a truck. One of the main streets on my work commute has the decorative bricks in patterns in several intersections. Some of them have moved because whatever is under them has moved, and this street has a LOT of traffic on it. When the rear wheels go over those bad spots, it feels like the back end is hopping. But with a decent load in it, the truck rides very well, and the long wheelbase helps with the stability on the road. And it tows well too; you barely know the trailer is there until you have to stop.
I ran 50 PSI in the rear tires for a while. It did improve the ride but the tires were starting to wear wrong. So I put them back to 65-70(depends on the outside temperature) and the wear patterns are normal. $200 a tire, I want them to last!
 

CalSgt

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I'm a visual guy, here's a graph to illustrate the load rating and pressure relationship, and the idea of load range E or other higher load tires as well. The OE design is to take the loaded max axle weights, determine the corresponding pressure, then apply factors to account for how low tires are expected to get, how much extra capacity, etc., which means that you get 3/4T trucks jittering around the road and feeling every piece of gravel. Dropping pressure based on ACTUAL tire load gets the ride back to the way tire designers intend them, since we rarely run loaded at the max weights.

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Auto manufacturers are also under tremendous pressure to increase the efficiency of their vehicles, customers want better fuel mileage and the federal government taxes manufacturers more in vehicles that are less efficient.

Maxing tire pressure is the cheapest economical modification possible: more air = less sidewall deflection = less energy required to move
 

Fjordlander

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V8
I have a 76 k10 so idk how helpful experience is for you and I know everybody hates on Rough Country but I bought new leaf springs for front and rear (2in lift kit) from them and my truck is smooth now. I also put bilstein shocks on the front and I had previously replaced all the body bushings which made the body sit a lot straighter.

It's still going to be more bouncy than a modern truck with coilovers but I can put my coffee in the cupholder and it doesn't spill like it used too.

The lift kit was about $650 and the bilstein shocks around $200 for just the front. I'm sure if I added bilsteins in the rear it would help even more but I'm happy with how the ride is now.
 

73cheyenne

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I took some of the shorter leaves out of the rear springs on my '73 K20. I had the front leaf springs re-arched at a spring shop to get more travel in front. I put Firestone air bags in the rear to get the load capacity back when needed.
I changed wheels to 17" aluminum and put radial tires on. If I'm not hauling anything heavy I keep the tire pressure at 35 psi.
I just have standard duty shocks, not stiff heavy duty. It rides much softer than when it was new.
 

Bennyt

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I know I already mentioned it but if you don't know about these, definitely worth your time to research. Makes your truck ride super smooth empty or loaded. They used to be made by BFGoodrich and I think Goodyear at one point for Buses and HD trucks. Everyone I know that has installed these all say that it was the best $300-500 ever spent on their trucks. I've installed them on 2-3 of my trucks over the last 25 years.

The SA-04HD I believe is the one I have installed on C30's.
On C10's I believe the 88-98 one can be adapted but you'd want to check with your local spring shop. I installed a set on my K5 but can't find the part numbers.

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