Author Topic: Leaf springs + airbags  (Read 21489 times)

Offline ssapach

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Leaf springs + airbags
« on: May 17, 2011, 04:40:10 pm »
So I've heard of people removing all but 1 or 2 leafs from their springs and then basically using the "helper" air bags to give them the lift that the leaf springs normally would.  Basically leaving the 1 or 2 leafs to keep the axle in position.

Sort of like a poor man's air ride if you will.

It can be aired up to carry weight or drop the air to smooth out the ride when empty.

Is this a bad idea?  It would seem to be that with so few leafs in the pack the axle wouldn't be rigid enough in its location and want to wrap and bounce a lot.

So, anyone here try this or know someone who has?

If it's a success I might consider it for my 1 ton, but if it's a bust I will gladly run away from the idea altogether.

Thanks in advance for any input.

Offline HAULIN IT

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Re: Leaf springs + airbags
« Reply #1 on: May 17, 2011, 08:28:53 pm »
I have basically what your describing on my truck. It still has 3 leaves with the airbag directly over the axle/spring on home-made brackets.
I air it up to level the truck while carrying extra weight. Not sure that taking all but 1 or 2 leaves out of a truck built for hauling that kind of weight is the best plan.
The shocks keep the vehicle from bouncing & traction bars keep it from wrapping up. Not sure any of this should really apply to a 1 ton truck though.
I checked through me file & don't have any pictures, however I could if you think you need them. Lorne

Offline Edahall

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Re: Leaf springs + airbags
« Reply #2 on: May 17, 2011, 08:50:32 pm »
So I've heard of people removing all but 1 or 2 leafs from their springs and then basically using the "helper" air bags to give them the lift that the leaf springs normally would.  Basically leaving the 1 or 2 leafs to keep the axle in position.

Sort of like a poor man's air ride if you will.

It can be aired up to carry weight or drop the air to smooth out the ride when empty.

Is this a bad idea?  It would seem to be that with so few leafs in the pack the axle wouldn't be rigid enough in its location and want to wrap and bounce a lot.

So, anyone here try this or know someone who has?

If it's a success I might consider it for my 1 ton, but if it's a bust I will gladly run away from the idea altogether.

Thanks in advance for any input.

My dad did the exact thing you mentioned on his chevy pickup and while it made it ride a lot softer, he did experienced some axle wrap under heavy throttle. However, the axle wrap subsided considerably once he corrected the axle vs. driveline angles. Also worth mentioning is he just left 3 leaves per side. My recommendation would be to just try it out and let us know how it works. If you do get axle wrap, you might have to correct your axle to driveline angles with some wedges. Also, there are ways to get rid of axle wrap such as installing traction / ladder bars.
1990 ¾ ton 4x4 Chevy Suburban
-Cummins Diesel - 12 valve - factory rebuilt
-6 speed bullet proof manual transmission - NV5600
-Gear Vendors Overdrive
-Upgraded Holset HX-35 turbo
-NP205 iron transfer case
-3.73 gears
-2" Lift

Offline ssapach

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Re: Leaf springs + airbags
« Reply #3 on: May 17, 2011, 09:24:43 pm »
The 1 ton rear springs have 10 pieces to each side and the fronts are just 4 each (last I remember anyways).  And with my old springs, I could always try a few times and keep removing more until i'm happy.

Making traction bars shouldn't be a problem for me either.

So if you've ridden in a truck with this sort of modification, how nicely does it ride compared to just the leaf springs?

Offline Edahall

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Re: Leaf springs + airbags
« Reply #4 on: May 18, 2011, 12:06:53 am »
So if you've ridden in a truck with this sort of modification, how nicely does it ride compared to just the leaf springs?

With this modification, it'll ride a lot softer.  However, the typical overload air springs are a little too small for optimal ride.  It ends up being a little bouncy.  What you need is a air spring that is a little larger to lower the resonant frequency.  Take a look at a Lincoln air spring to give you an idea of capacity.
1990 ¾ ton 4x4 Chevy Suburban
-Cummins Diesel - 12 valve - factory rebuilt
-6 speed bullet proof manual transmission - NV5600
-Gear Vendors Overdrive
-Upgraded Holset HX-35 turbo
-NP205 iron transfer case
-3.73 gears
-2" Lift

Offline slammed79

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Re: Leaf springs + airbags
« Reply #5 on: May 18, 2011, 12:23:53 am »
You mentioned a "poor mans air ride"

Are you trying to get better ride quality or lower stance?
Lower stance with helper bags will do you fine, but you can run a bag bigger than a helper for the same or less money. I might reccomend Slam Specialties RE7 or 8 bags with just 2 leafs.  Traction bars will help, or a panhard bar. Those bags will give you weight rating to tow and not bottom out.

I'd leave at least 3 springs and go with the air bag that I mentioned, with a shrader valve set up, pull up to a gas station and air up as needed.
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Offline ssapach

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Re: Leaf springs + airbags
« Reply #6 on: May 18, 2011, 08:48:38 am »
I only stated "poor man's air ride" as someone once referred to it as that.....not here though, somewhere else in internet land.

I would like to maintain stock ride height, if not gain an inch or too by inflating the air bags more at times when I wanted.

The truck will be used for a mixture of things, work and just cruising around.  So for the "cruising" time, being able to dump some air and have a smoother ride would always be a plus.

This is something I would experiment with on my truck's stock springs first, and if I were to enjoy it like that I could leave it.

The idea here is also to help out the old saggy springs.  The front isn't quite level and the whole truck does sit lower than it would from factory, but I guess that's to be expected after 25 years.  The air bags will lift it all up a bit and allow me to level it out too.

The other issue is that with the removal of some of the leaves, it would actually sit lower initially.  So either that space gets made up with some small blocks/wedges or hopefully won't require that and that space would be made up by the lift that the air bags would supply.

The loss of ride height would be more noticeable in the rear, the 10 pack leaf spring is about 4" thick (just guessing).  So trying to make up that much ride height with the air bags might actually just prevent what I'm trying to accomplish here anyways.

Offline Edahall

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Re: Leaf springs + airbags
« Reply #7 on: May 18, 2011, 09:19:36 am »
I only stated "poor man's air ride" as someone once referred to it as that.....not here though, somewhere else in internet land.

I would like to maintain stock ride height, if not gain an inch or too by inflating the air bags more at times when I wanted.

The truck will be used for a mixture of things, work and just cruising around.  So for the "cruising" time, being able to dump some air and have a smoother ride would always be a plus.

This is something I would experiment with on my truck's stock springs first, and if I were to enjoy it like that I could leave it.

The idea here is also to help out the old saggy springs.  The front isn't quite level and the whole truck does sit lower than it would from factory, but I guess that's to be expected after 25 years.  The air bags will lift it all up a bit and allow me to level it out too.

The other issue is that with the removal of some of the leaves, it would actually sit lower initially.  So either that space gets made up with some small blocks/wedges or hopefully won't require that and that space would be made up by the lift that the air bags would supply.

The loss of ride height would be more noticeable in the rear, the 10 pack leaf spring is about 4" thick (just guessing).  So trying to make up that much ride height with the air bags might actually just prevent what I'm trying to accomplish here anyways.

It'll ride pretty rough if you add air bags and not take out leaves unless you use the air bags to lift it way up past the stock spring height.  As mentioned, I also agree with using 3 springs and some large volume air bags.  The larger the air volume (capacity), the less bouncy it'll ride.

Yes it'll sit lower when you remove leaves however, you use the air bags to lift it back up.
1990 ¾ ton 4x4 Chevy Suburban
-Cummins Diesel - 12 valve - factory rebuilt
-6 speed bullet proof manual transmission - NV5600
-Gear Vendors Overdrive
-Upgraded Holset HX-35 turbo
-NP205 iron transfer case
-3.73 gears
-2" Lift

Offline HAULIN IT

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Re: Leaf springs + airbags
« Reply #8 on: May 18, 2011, 10:16:26 pm »
with a shrader valve set up, pull up to a gas station and air up as needed.
Funny you mentioned that!

I went out to the garage & took a picture of mine for you...right now they have a few pounds of air in them, they blow up rather round when aired to 20 psi or so & can raise the truck several inches.

The airbags definitely help with stabilizing the lean with some weight in the bed while going into a corner. I leave just a few pounds in them (per the manufacturer's recommendation) unless I'm hauling more than a couple hundred pounds, then I air it up to make up for the sagging so the snubbers don't bang. Lorne


Offline ssapach

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Re: Leaf springs + airbags
« Reply #9 on: May 19, 2011, 09:52:25 am »
Thanks everyone for all the info on this.

This is exactly the kind of stuff I am looking for, perhaps I will go this route when I get working on my old truck.

Offline Captkaos

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Re: Leaf springs + airbags
« Reply #10 on: June 27, 2011, 05:11:58 pm »
N2TRUX ran this setup on his truck before upgrading to Ridetech stuff.

Offline Irish_Alley

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Re: Leaf springs + airbags
« Reply #11 on: June 27, 2011, 05:49:53 pm »
what are air shocks for?
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Offline roadrage41

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Re: Leaf springs + airbags
« Reply #12 on: June 28, 2011, 02:17:41 am »
3rd Gen f-bodies  ;D
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