proper use of air shocks

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str12-340

str12-340

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So I have seen plenty of posts here saying that you should NEVER put air shocks on a car and I have seen air shocks used improperly to cover up worn out leaf springs in a car, or to jack it up to a place where the rear suspension simply doesn't work. Today I started packing for a Thursday departure to the Rod Run to the End of the World in Ocean Park on the Long Beach Peninsula of the coast in Washington State, it's a 300 - 400 mile round trip and we will be gone for 7 days. This is what my trunk looks like at this point:
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There is stiff stuck in every available nook and cranny including tool boxes, road disaster supplies and everything we need to live for that time. We are now in the process of filling the back seat up!

The leaf springs are 6 leaf ones from ESPO, maybe 4 years old. I checked the ride height in the back before I loaded it, and when it's full of maybe 5-600 lbs of stuff I'll add maybe 25 lbs of pressure in the shocks and bring it back to the usual ride height for the trip. Once we get there and unload into a rented cabin, I'll bleed some air off to restore proper ride height for 6 days of running around, and then visit a shop when it's loaded to go home to add air for the ride home.
 
Do some load relocating

Move the heaviest items to the floor of the back seat. Next heaviest to the back seat least heaviest to the rear (by the latch) of the trunk.

That way you don't have as much weight behind the axle centerline
 
Just know that you are putting way more load on the shock mounts than they are designed for, even with "only" 25 PSI. Just keep your ears open and get under there and look whenever you stop for gas and food.
 
I used air shocks for years when I had a boat. I even had them on my 68 barracuda back in the day. Never had an issue. However, the metal was about 40 years newer on the car back then. I think “never” is pretty extreme.

Loading the upper shock mount can be a concern. However, they are loaded every time you drive it & hit a bump. If the upper shock mounts aren’t bent or loose, you will probably be ok for awhile.

‘They used to sell leaf spring helpers back in the day that bolted on to the existing leafs and performed the same function. Would think they are cheaper than air shocks.
 
as long as you understand that "proper" also means 2 valves and 2 dedicated lines
(otherwise, you take a left hand turn, and the car sways a little to the right, shifting the load
guess what happens to that fight shock that now has a higher load on it? if you have one line, it will collapse as the pressure moves to the other side)
 
I've had air shocks since a few weeks after I drove it new from the dealership.
I quickly installed them as that is what I used in my 62 Wedge.
Following the Mopar Chassis Manual, all we had, or needed back then was clamping springs, pinion snubber, and air shocks to preload, same as adjustable coil-overs now.
Preload pressure was in the teens, - however with the car loaded for holidays, towing a ski boat fulla camping gear, 4 people in the car, air shocks up to whatever needed to stop tires rubbing on corners.
Those air shocks ; (newer ones) are still on the car today and the shock mounts are just fine ! !
I'm sure somewhere on the East Coast there are rusted out POS that may have had issues with upper mounts, but I've let fear and common sense be my guide .
Cheers .
 
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RustyRatRod said:
Just know that you are putting way more load on the shock mounts than they are designed for, even with "only" 25 PSI. Just keep your ears open and get under there and look whenever you stop for gas and food.
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So my experience is much like the one inertia posted in #7. My first air shocks went on this car in 1973. I have driven this Dart well over 200,000 miles. I have air shocks on both of my other 70 Darts and we travel in them quite a bit, so 49 years of using them tells me that concerns about them are not based on experience, but rather horror stories where they were improperly used. We have Mopar friends who travel with us to several shows a year in their 1973 Satellite station wagon, which came from the factory with air shocks installed and fill valves in the rear door jamb.
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Joey4speed said:
Pillows?
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We stay at a cabin at an old renovated fish camp - there are wool blankets in there too!
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diymirage said:
as long as you understand that "proper" also means 2 valves and 2 dedicated lines
(otherwise, you take a left hand turn, and the car sways a little to the right, shifting the load
guess what happens to that fight shock that now has a higher load on it? if you have one line, it will collapse as the pressure moves to the other side)
Click to expand...

just how long are you thinking I'll be in a turn, and how big do you think those itty bitty air lines are? I understand what you say in theory, but not in practice. This particular car has a bunch of USCT frame stiffening done and a nice Energy Suspension sway bar up front so it doesn't lean much :thumbsup:.
 
diymirage said:
as long as you understand that "proper" also means 2 valves and 2 dedicated lines
(otherwise, you take a left hand turn, and the car sways a little to the right, shifting the load
guess what happens to that fight shock that now has a higher load on it? if you have one line, it will collapse as the pressure moves to the other side)
Click to expand...

Interesting, I have never thought about it that deeply. I have never heard of independent air systems for each shock, but seems like it would be useful if you were trying to preload one side.

I have never observed this effect on my cars, so I would think it would be very minor. As noted above, not a lot of pressure, & pretty little tubing.
 
Uneven load squeezes air outta one shock, fills shock other side, not only does load lower one side, but the displaced air lifts other side, - car leans more .
 
You don't want to carry heavy items inside the passenger compartment. I had a friend get killed by a metal tool box that was on the front floorboard of his pickup, he had a roll over accident. The heavy item was extremely fatal.
Dana67Dart said:
Do some load relocating

Move the heaviest items to the floor of the back seat. Next heaviest to the back seat least heaviest to the rear (by the latch) of the trunk.

That way you don't have as much weight behind the axle centerline
Click to expand...
 
My best friend, when we were 16, got a 68 Dart GTS 340. It was a nice car. His brother gave him a pair of deep dish slotted chrome wheels. He mounted some L60-14's He put airshocks on with the extensions. The back bumper of the Dart sat about chest level, needless to say he wrecked the car due to the very ill handling.
 
I always thought air shocks were there so you could raise up the back end.

Because it's easier to go fast when when you're always going downhill.
 
lemondana said:
You don't want to carry heavy items inside the passenger compartment. I had a friend get killed by a metal tool box that was on the front floorboard of his pickup, he had a roll over accident. The heavy item was extremely fatal
Click to expand...
There is that, but propperly restrained...
 
Vehicles that had come from the factory with air-shocks also had their mountings beefed up to handle the additional loads placed on the mounts. 70 year old technology.
Airbags mounted between the housing and frame are the current norm. No mount load.
I didn't see any one mention that you also need to re adjust the air pressure in the tires accordingly.
 
think a recurve and heat treatment of the standard springs and a rebuild with pure zinc interleaves is value for money... get the height set where you want it and get the spring hardness/rate set so that it doesn't squat when the boot is full or you tow.

its a brutal process involving a big vice, a torch and a big hammer.. but once the shape is achived and the result heat treated all good. a place that specialises in farm machinery and truck springs is ideal and its never as expensive as you think it will be, they do this all day, and car springs are small cross section in comparison to those off a trailer.

its not exactly precise but i'm yet to find somone who didn't like the result once everythng settled back in
getting the spring pack back together could be a struggle threaded bar and clamps necessary and then some nice cap head high tensile bolts

depends how much you want them to do...

think mine cost £160
 
inertia said:
Uneven load squeezes air outta one shock, fills shock other side, not only does load lower one side, but the displaced air lifts other side, - car leans more .
Click to expand...
I had air shocks on my 72' Dodge Van to rid the rear sag. I installed them on one line. Reason was if and they did leak, the rear would drop the same on both sides. No one mention the shackles extensions for raising the rear. On my B300 Van I just turned the rear shackles over and gain around 4". No more leak down, problem solved!!!!
 
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