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Leaf Springs - Build Your Own Pack

107K views 253 replies 31 participants last post by  ADDvanced 
#1 ·
I've been PM'ing with WoodButcher about his spring pack that he assembled from various leaves
from more than one vehicle. Rather than keep the discussion in the dark,
here's a thread where all can contribute and benefit.

The concept -
Use various leaves out of various springs to built the height and load carrying spring that you want for your van.

My 89 has glass springs. They don't look frayed or broken at all but I want LIFT. So I'm
replacing them with steel leaves.

Here's the two springs I'm working with (I bought a complete pair of each, only showing one of each in these pics).
The shorter spring is from a 99 Astro.
The taller spring is from a 2001 S-10 pickup, 2WD, 4.3 V6.
It is exactly the same dimensions as Astro/Safari steel springs - 26x28 - 2.5" wide.






About 3 3/4 inch difference in the height of the springs at rest... :banana-parachute:


OK. Here's a question for the spring rebuilder experts.
In the photo below, the clamp thingies in YELLOW, those appear to be rivited on.
I had to bend the fingers away with a BFH to get the captive spring out.
Also, the nylon/plastic insulator thingies in RED. Those appear to be mounted with a
"one time only" push on connector. I had to destroy those to disassemble the sandwich.

The question, do you reuse those same clamp thingies (the YELLOW circles)? Or do you
use some kind of alternative that is bolt on?

AND

Surely you buy new nylon insulators (the RED circles). I've seen several types listed in catalogs.
Do you replace with the exact same style or is there a better, stronger, groovier style and do they
push into place with that same kind of "ladder lock - one time only" connection?



Here's the disassembled S10 leaves, wire brushed and primered with rust converter.


The +1 spring on this S10 pack is a real monster!... :character-cookiemonster:




Domestic animals always seem to enjoy hanging around while I'm working on any project....:animals-dogrun:
Circled behind the palm tree, Harley the horse.


Lump
 
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#2 ·
Just heat the clamps up with an acetylene torch if you got one, then bend them back. In fact, looks like you could probably bend them with a large C-clamp. That's what I did. As for the spring pads, I don't know. I just reused what was left of mine. I think they are more for noise reduction than anything, and also prevent your springs from wearing out.
 
#3 ·
X2 on those guides, if you have a torch, use it. I don't so I used a bar to spread and a big clamp and hammer to close it.

Just to be sure I didn't give bad advice in our PMs here is the gist of the conversation-

Me-
"If you don't carry loads more than 75% of the time don't add leaves. It will ride like a buckboard on a bad road. My van rides hard with just my tools which put me right around the GVWR, when I load lumber or equipment it rides nice. Use the springs you have with the most arc with all the factory hardware steel shims in the center and nylon slides at the ends. The slides on mine are long gone so she squeaks unless greased often.
If I were after lift with no load I would use a shackle lift rather than block under the spring, IMO using blocks like that is asking for trouble, I don't know the terminology for it but those blocks move the axle away from the spring and the spring is what is meant to keep the axle straight with the body.

If you make a post asking what you want to do, want to accomplish, ride, handling and so forth I'll post explaining what I do. I'm sure others know better than I for lifting and comfort."

Lumpy then asked,
"When you mounted your (now thicker) spring pack at the axle, you had to use longer
U bolts, obviously. What about the other side of the anchor plate? Those bolts on the
bottom part look pressed in. Did you have those removed and replaced with longer studs or ???"

Me-
"They are standard bolts if memory serves, I removed the stock bolts and added spring back in '01 so I'm a little foggy on that but there are no bolts pressed or otherwise permanently attached to the clamshell. If you add spring these need to be longer as well.

Also! if adding leaves you need a longer bolt to hold the pack together, be sure to get hardened bolts, grade 5 are ok,, 8 is better."

Thats it,,,
so guys, I'm no mechanic, my knowledge is only from what I've done to all of my trucks since I started hauling my own tools in the eighties so if I've been doing something wrong clue me in too. Lump says he does not carry loads very often and I would try to persuade him not to bild a thicker pack but to use the S-10 spring as is and add a shackle lift to preserve the ride and his backside. I think the S-10 spring will give a little lift and add load capability as it does have the +1 load bar at the bottom.
What say the mechanics here?
 
#4 ·
Not a mechanic here, but I've done lots of rear suspension work on my van. Lumpy is right about the studs, I ground/chiseled/drilled them out and replaced them with bolts before I went to 4" blocks with all 4 u bolts and a top plate. Use grade 8 hardware if possible, our Lowes sells it around here, if not available grade 5 will work. I got the grade 8 center bolt at Carquest.

How much lift are you looking to get, Lumpy?
 
#5 ·
I built my own spring pack using the springs from the astro and a 96 s10 blazer i put the packs together using the center bolts from the s10 and i used the BFH to close the clamps again, i never reused the plasttic pieces that go on the end of the leafs... They are mostly for sound proofing the springs that way you dont get the squeaking of metal on metal rubbing,which i get on occasion on a hot summer day
 
#6 ·
Hmmm... So if the free height difference between the two packs is about 3 3/4", would it be safe to say that it would lift the rear at least 3"? If it's closer to 4", that might give too much rake on my van. I'd have to go shackles which would I wouldn't mind. I don't like the idea of blocks though.
 
#7 ·
Those of you that have done this, What is your ride like, loaded and empty? what did you do or add?

Trapper,
I have no experience w/ blocks, can you clue me in? My biggest concern would be pulling up a hill loaded as I carry tools at all times. You have no concerns that these can twist? Keep in mind even with a G80 or another style locking rear end on clear, dry pavement we have only one drive tire unless you have a locker and then they only lock when one slips so all the force is on one side. If lumpy wants more than 2" of lift I think ither shackles or blocks would be the best way to go.
Also with your lift, your on stock springs right? do you use a rear sway bar?

Shadow,
I don't think he'll get that much lift from the S-10 spring. It appears to be the same weight except for the flat helper on the bottom and a good arch to it, (stop me lump if I'm wrong) so IMO the gain would be closer to 2". I'll bet these would be perfect for a nice solid ride loaded or not.
 
#8 ·
How much ride am I seeking?
Not sure. I have 2" shackles now. When I install the S10s I'll use the same 2" hole
and see what the lift is like.

I tend to agree (guess) with woodbutcher that just because the unloaded springs are 3.75 taller,
I will probably not get 3.75 lift. Their tight arch causes them to be shorter. They will need to
lengthen once in place and that will reduce the lift.

OTOH, the glass springs in there now are nearly flat. As close as I can measure, they
are only 1/2" taller at the ends than at the axle. So somewhere between the switch
from glass to steel, and steel Astro to steel S10, I'm guessing I'll easily get 2", and
likely 3.

That would give me about 5" total with the shackles. Then I can fine tune them by simply
choosing another shackle hole. Hard to imagine I'd want LESS lift. If I could somehow get
8" of lift, I'd do it and then buy wheels and tires to deal with the extreme.

I think(?) that with the lift created by the higher arch springs, I'll be able to use the
S10 plates instead of the Astro clamshell anchor plate. Then I can use two hefty
U-bolts. Those U-bolts on Astros seem VERY tiny compared to the larger diam S10s.
If the lift it high enough, the upper-inboard side of the spring plate may not be a factor
in terms of hitting the frame member upon spring compression.

Here's something I found about S10 springs -
In Astro steels, the SHORT (26") end of the leaf goes to the REAR of the van.
In S-10 steels, the SHORT (26") end goes to the FRONT.

Also, the S10 springs use two different sized end bushings. In S10s, the REAR
bushing is 1.5" diam, the FRONT bushing is 2" diam. In Astros, both ends are
the same. SO - When you install S10 springs you'll be reversing them from the
way they sat in the S10. What was rear now becomes front. One point of confusion
is then the bushings. When you're searching for leaf spring bushings, the REAR bushing
on the S10 will now be the FRONT bushing on the Astro, and vice versa.

Lump
 
#9 ·
What are you doing to the front?

I would think you will get at least 3" of lift--I would imagine that the S-10 springs will just pull the shackles farther forward. You may have to deal with your wheels sitting too far forward, I don't know how that will end up. If they do, you can compensate while increasing your lift by installing blocks with offset holes. I could post pics of my setup...I used metal that I had laying around to fab my blocks and plates, so it's not pretty, but works well. I know some guys have posted their :2: about blocks, but I haven't had problems. When I am driving on really uneven surfaces

my tires occasionally rub on the body, but not too severely. I have only about 750 miles on the van after I went from 5" to 8" of lift, but I have done some crazy things with it and had no problems.
 
#10 ·
What am I doing to the front?

Waiting for these other guys to get further into their experiments with coils to know which
one does what and how tough the ride is.. :D

You might be very right about the shackles rotating to deal with the taller arch in the S10 leaves.
Esp since I have a longer than stock shackle (2" lift).

As far as the wheels sitting farther forward, I will turn the front hangers around.
The spring mounting hole in those is off center. So reversing the hanger gives you
about an inch+ of shift of the wheels toward the rear. Guess we should all be
checking our pilot shaft when we do that to make sure we've still got
enough diddly in the squat.

Please do post pics. Did you use some kind of plate w/ U-bolts like an S10 or universal,
instead of the stock Astro clamshell?

Lump
 
#11 ·



As you can see, I fabbed the blocks with scrap metal, so they look a little messy. The spring plates i also made from some 1/4" stock I had lying around.

Woodbutcher, I missed your question about the blocks causing twisting. On rare occasions, my tire rubs on the front of the wheel well, but it is pretty close anyway. I tack-welded the blocks onto the perches to reduce the potential for the blocks to slide around. So far, no problems with the blocks, I wouldn't hesitate to do it again.
 
#12 ·
Oh, and Woodbutcher, right after the build I went on a camping trip with my family (9 people and a boat trailer full of stuff) with absolutely no problems. I think the only time you would possibly run into problems is severe off-road conditions. I beat the heck out of my van and the only problem I have had is that a couple small tack welds I put on my blocks failed (bad welds). The blocks didn't move, though. As for the ride, I have OLV add-a-leafs on the back and re-indexed keys on the front. The ride is a little stiff, but not at all unpleasant. It handles off-road quite well, but is not as nice as stock suspension when on moderately bumpy roads. I like the ride, all things considered.
 
#13 ·
Trapper, thanks for the pics.

What size other than length (what diam and throat spacing) are your U Bolts?
The S10 size bolts I have are 9/16 x 3 1/4 x 7. They seem a little wide throated
for the Astro axle but I don't really know how U bolts are supposed to fit.

Does your top anchor plate ever hit the bottom of the "frame" when you hit a large bump
and cause the wheel to move upward?

Lump
 
#14 ·
Thanks for the input trapper, having towed with a load inside is the kind of test that matters.
:thumbup:
When I see those blocks on any truck it looks to me like the top of the block would act as a pivot point putting great stress on the u-bolts. If those blocks were longer front to back like an inverted triangle I would feel better about using them on my van.

Think about this, If those are made from square tube stock, the top piece being half again as long and all welded up a second set of square u-bolts around the upper tube and spring pack, maybe the top plate longer to catch all 4 u-bolts. I'm probably thinking in the land of overkill here as were not talking rock crawlers w/ supercharged engines but,,,, what do you think? Would that cure any fore and aft movement?
 
#15 ·
MONSTER Leaf Springs?

The guy that delivers our bales of hay came in a 3500HD flatbed.
I was drawn to the leaf springs. Look at these monsters -



The overload springs have overload springs. And either set separately are
bigger/more leafs than our biggest Astro pack -


The spring pack on the BOTTOM is the primary set of springs. They are engaged all the time.
When the truck is loaded heavy, the top set comes into play with it's own set of frame bumpers.

A 4+1 spring pack with a 6+1 overload spring. 12 leaves total. Each one is REALLY thick
and I think 3 1/2 inch wide. 15,000 GVW rating.

Still with all that monstrosity, I noticed that the nut was missing from one side of the
rear sway bar. He had it wrapped with 17 ga aluminum wire, the kind we use for horse
area hot wires.

Lump
 
#16 ·
Shadow (and others) PM'd me and asked about my current plans for replacing my stock glass springs
with taller S-10 leaves. I'd like to keep plans about all this out here on the forum so
that those with comments and ideas can chime in.

My set of S-10, 3+1 leaves, are dismantled, wire brushed, primered and painted.
I got new bushings yesterday. Now I need a few little parts like the nylon/plastic
isolator things that go on the ends of a coupe of leaves, couple of this-n-that's etc.

Here's one concern and my planned resolution.
Consider the items in YELLOW in the pic below. We're looking at the LEFT wheel, viewed from the rear -



Notice the "anchor plate" (the clamshell) that holds the springs to the axle. U-bolt in the
outboard side, half clamp on the inboard side, both below the axle.

Consider the items on the TOP half of that clamshell. The glass springs are 3 inches wide
PLUS they have a rubber spacer that adds 1/4 inch to each SIDE of the spring, in order to
fill up the clamshell. That means the total inside width of the clamshel is 3 1/2 inch. Installing
2 1/2 inch wide steel springs into that 3 1/2 inch wide space leaves an extra half inch on
each side of the spring. I don' t think I like that.

SO - Here's my thought on how to "fill up" that space.
Build an "extra leaf" out of 3 1/2 inch wide steel. Make that "leaf" out of 1/4 inch THICK steel
but instead of make it as long as a typical add-a-leaf, make it only 6 inches long, the length
of the clamshel from front to back. Drill a hole in the center of that "extra leaf" and bolt it
to the rest of the spring pack, just like you would a regular add-a-leaf, but bolt it on TOP
of the pack. Now you've got the TOP part of the leaf pack wide enough to "fill out" the clamshell
and keep things nice and stable. I may do the same thing at the bottom of the new spring pack,
add a short, 3 1/2 inch wide piece of steel there and bolt it to the pack as well. That will center
the leaf pack over the spring perch. The perch, of course, has a hole designed to hold the bolt head
so the pack really isn't going anywhere. BUT, filling in that extra half inch of space on both sides
of the pack just seems like good engineering. Asking a 10mm bolt to pull the leaf pack together
is one thing. Subjecting it to possible side loads is probably not what it's best at.

I got the idea from several hours of just laying under there, looking at the assembly, and then
seeing this product -
http://offroaddesign.com/catalog/Zero%20Rates.htm

As an added bonus, I'll gain another 1/4" of lift, or whatever thickness I use to make the plates.

Pics, of course, when it happens.

Lump
 
#18 ·
What's up with that rubber pad? I'm thinking it's to keep the fiberglass leaf in place since a hole in a fiberglass spring isn't a good idea. Is it necessary to keep? I'm not even sure if there's one on my 2000. If there is, I'm gonna remove it to make room for my planned 4-leaf pack.
 
#19 ·
Shadow - That rubber "surround" thing is indeed weird. They probably only used them on the glass springs
to reduce friction on the fiberglass. Staring at those darn things again and again is what got me
thinking of using a steel version for the replacement pack. If we were to try and use the rubber
thing for the steel springs, it would STILL be too wide for the spring by 1/4" on each side.

And Jasen - True that. Not really a "leaf" since it's not doing any springing. But not
really a block since it's not really doing any lifting, unless you use one in the bottom
and then it's only a quarter inch. In the commercial version in the link, one of the
reasons for using appears to be mounting the axle more forward or rearward. That's
a consideration here as well. But we'll be getting an inch or so moved rearward as it
is by reversing the front hangers. If I need more, I'll consider something like the off
center block in the link. And heck, I'll gain another inch!

Lump
 
#22 ·
I checked again and yes, there's a rubber pad on both the bottom and top of the pack but they don't surround it. Looks like my bumpstop went bye bye too. :shrug:


My yard is not level but that rear definitely needs to go up!


The spring packs I pulled off a 93 S10. To my disappointment, they look like the soft ride pack. But they were only $12 a piece. There was one newer S10 that had a 3+1 pack but they looked tweaked probably because the front end was destroyed from a wreck.
 
#23 ·
Thanks for taking that pic of your steelies, Shadow.
Same direction and all as my pic. Makes it easier to see the difference.
If my rubber things are still in good shape, perhaps I'll consider incorporating them
into the sandwich.

I wonder if I could build new rubbers out of high torque RTV, the grey stuff...Hmmm :confused:

Lump
 
#24 ·
Lumpy said:
I wonder if I could build new rubbers out of high torque RTV, the grey stuff...Hmmm :confused:

Lump
Windshield urethane is some tough stuff when it's cured. I actually used it today to fill the torque mounts on my wife's Saturn. Note to anyone who uses it, I would get an air-powered caulk gun if you don't already have one. Trying to squeeze that stuff out manually is a super PITA due to it's thickness.
 
#25 ·
Finished wire brushing and rust reform/priming my S10 springs. Now applying Desert tan flat rustoleum.

Here's a couple of pics of the front hangers, standard OEM Astro 96-05 parts, that will replace
my standard OEM Astro 85-95 clamshells. These pics show pretty well how the single hole that
is used for mounting the spring is OFF CENTER. In it's normal usage, the entire hanger is mounted
so that the hole is more toward the FRONT of the van. That puts stock steel springs into a position
that centers the wheels within the wheel well. When you use higher arch springs, they are the same LENGTH.
So the arch tends to bring the axle FORWARD. Simple solution is to turn the hanger brackets around, now
causing the off center hole to be an inch or so more REARWARD.

Hope that makes sense. Here's da ho's -







The hangers are actually stamped with "FRT -->" so in use, you simply turn them so the arrow points to the rear.



Lump
 
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