Daughters ‘87 needs to ride smooth.

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Grit dog

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I didnt realize all the info needed for the questions. You’re right they’re 31x10.50x15. It’s a 350sbc. I’m going to drop the pressure on the tires (pressure was filled to max psi)and see how that may help, thanks.
That will be huge.
 

Redfish

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My memory of those trucks seems to be different from most of you. The 2wd square bodies were usually pretty smooth riding. I cannot remember how many times in the '80s I heard someone say, "This truck rides like a car!" Of course the top of the line trucks came with white wall "car" tires.

It looks to me as though your tire choice is not helping you. They may look cool but if they are aired up to max pressure, they are going to be stiff. @Grit dog and I are in agreement on this.

I would try replacing the front coils with a new set as close as I could get to the OE spec. The leaf pack in the rear rode pretty smooth in its day. You can affect the ride quality front and rear with the right shocks also. When that truck was new a set of Monroe Gas Magnum shocks would really make the ride stiff but they helped it handle better on a curvy road. The factory shocks were usually shot after 30K miles or less.
 

legopnuematic

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My big ten has lots-o-leafs too, the original owners even added a 3 or 4 leaf overload pack on top.

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I’ve got 31x10.50x15’s (BFG K02s) on a 15x8 wheel on my 76 c10, I’ve put 30-40k miles on them and I don’t think it rides bad at all. That is even taking trips up to northern IL and southern Wisconsin with their barely existing roads (looking at you Winnebago County) and vehicle swallowing potholes (Milwaukee).

Maybe I just have low standards or expectations.
 

gogo14910

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My big ten has lots-o-leafs too, the original owners even added a 3 or 4 leaf overload pack on top.

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I’ve got 31x10.50x15’s (BFG K02s) on a 15x8 wheel on my 76 c10, I’ve put 30-40k miles on them and I don’t think it rides bad at all. That is even taking trips up to northern IL and southern Wisconsin with their barely existing roads (looking at you Winnebago County) and vehicle swallowing potholes (Milwaukee).

Maybe I just have low standards or expectations.
Is it softer ride to have more or less leafs?
 

legopnuematic

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Yes and no. It depends on quite a few factors.

The thickness of each leaf, the width, the overall length, shackle configuration.

If you look at a trailer spring, they are fairly short, narrow, thick leafs with just a few of them in a pack, they are rated for pretty high loads.

Or a (say for example 2nd gen dodge truck) “newer” 3/4 ton, my Cummins has 3 or 4 leafs in the pack, but they are 3” wide and thick leafs, aftermarket springs sold by Carli have at at least 10 leafs, but are thinner, and are rated lower than what the factory setup are (for payload), but should ride smoother and promote more flex and travel than OE.

So it really depends.
 

Hunter79764

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Start with 25 psi all around and see what that does, I bet you'll be amazed. Then dig in on bushings and springs, or maybe go shocks first. No experience on brands for smooth ride, but if you REALLY want the 77 Caddy ride, I'm sure someone has a set of blown out stock shocks they could send :) Otherwise I think cheaper shocks would be smoother after a break in period, but something like Bilstein is going to be objectively "better" but not necessarily float down a lazy river smooth.
 

squaredeal91

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These squares IMHO ride better than new cars. New cars/trucks ride smoothly but still feel like a brick. Not a popular opinion but that's how i feel. My k10 shorty has an all wood bed on it and is too light kinda hurts my back on bumpy roads. (Putting original bed on soon) rides much better with weight in the back. I'm constantly leaving things in it for a better ride. It has the quad shocks on it all around. I know I can improve my ride by removing half of them I bet. Even heard guys sometimes drill holes in half of them to make them dummies. My sons 85 2wd fleet long rides really nicely the way it is.
Springs play allot here and so do tires as well pointed out.
All this to say lol. Monroe makes a self adjusting gas shock that stiffness on windy roads and softens back up when on flats or whatever. I haven't personally used them but have always planned getting them for my car. The guy who told me about them really liked them.
 

AuroraGirl

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Sorry R10, 2wd
replace all bushings

Anything sprung weight that can be reduced will help, but theres only so much you should lighten on the front end, and thats Maybe? with aftermarket arms? I could be wrong, but i dont imagine that would save much weight

The proper shock, and as said, the rear spring situation

But if you can isolate the cab from the frame with a custom or aftermarket cab mount, that might help. Nowadays instead of engineering trucks and frames they just engineer NVH isolation methods for the cab, gmt900 trucks are notable for this because its functionally a gmt800 frame and all that, but the cab mounts are entirely different.

Late late gmt800 got some of the engineering changes as running changes , TSBs on them make it look complicated as hell and frankly dumb, in my opinion, but if you wanted to reverse engineer modern truck cab mounts to your square that would probably make it ride a lot nicer. Then a new rag joint for the steering wheel, little rubber bits for the rear leaf springs that limit the slap and vibrational transfer from the axle

having good engine/trans mounts

Dont do poly.

THen good PT tires

But at that point you have spent so much time trying to make the truck not a 1987 Chevy, why not just get a 2wd gmt400 from the mid 90s? Would be smoother and has more interior love that also isolates (remember, insulation, trim, rubber seals.. all play a part.. you could do this to your square too.. but its time and money. )
 

Grit dog

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My big ten has lots-o-leafs too, the original owners even added a 3 or 4 leaf overload pack on top.

You must be registered for see images attach


I’ve got 31x10.50x15’s (BFG K02s) on a 15x8 wheel on my 76 c10, I’ve put 30-40k miles on them and I don’t think it rides bad at all. That is even taking trips up to northern IL and southern Wisconsin with their barely existing roads (looking at you Winnebago County) and vehicle swallowing potholes (Milwaukee).

Maybe I just have low standards or expectations.
WOW! That’s way more spring than axle!
You have basically the same truck and tires as the OP. Maybe share your tire pressures when running around bobtail.
 

legopnuematic

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WOW! That’s way more spring than axle!
You have basically the same truck and tires as the OP. Maybe share your tire pressures when running around bobtail.
So the photo above is of my 79, that has not been driven yet. So I cannot speak to how it rides. But the springs are "Blueprinted" from what originals were, 79 Big 10, 6200lb GVWR, 56" springs. Had them made at a local spring shop, they pulled the information from their vintage books.

But if I step in the bed I can flex them, or wiggle the truck. So I don't believe it is going to be a total log wagon.

Here is a photo of the original 79 springs with overloads, there is/was wear on the rubber bumpers that I believe it was loaded enough to use the overloads on multiple occasions.
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Now my 76 is a non F44 (non big ten truck), 5400lb GVWR, 52" springs. Best photo I could find that you can see the springs. 6 leafs I think?
You must be registered for see images attach


But I have put about 60k miles on the 76, I've always thought it rode fine, never any complaints from others. There has been a 30 gallon engine drive compressor living in the bed for 4 or 5 years now, so that certainly would help. Even before the compressor I never thought of it as a log wagon.

I don't remember what I have for tire pressures, but it's probably 35-40psi all around on the 31s.

With the 235/75/15s before it was what the door chart says, 28 maybe?

Maybe I just have low expectations or high tolerance to ride quality... I think it (and the Cummins, and dart) rides better than a lot of new cars do, if says something.
 

Rusty Nail

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It’s not a rotisserie restoration. I’ll put money in but, she wants the “old” truck. I just want her to have a smoother ride. i.e. dont spill coffee on the interior we just redid. Too bumpy for that right now even on a concrete hwy.
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:
 

Bloodhound1981

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I didnt realize all the info needed for the questions. You’re right they’re 31x10.50x15. It’s a 350sbc. I’m going to drop the pressure on the tires (pressure was filled to max psi)and see how that may help, thanks.
I am running 31x10.5x15 Michelin LTX Defenders, I went from 40psi to 32 and I couldn't believe the difference in ride quality, as far as being less harsh.
 

Grit dog

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I am running 31x10.5x15 Michelin LTX Defenders, I went from 40psi to 32 and I couldn't believe the difference in ride quality, as far as being less harsh.
^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.”
 

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