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Airbag rear spring helpers or rubber rear spring inserts? To prevent rearend squat at full load.

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April 28, 2017, 06:34 PM
Black92LX
Airbag rear spring helpers or rubber rear spring inserts? To prevent rearend squat at full load.
When loaded the van goes full squat

No load no squat


There are two options to remedy this issue adjustable airbags that cost $100 and installation is cake. As nothing needs to be removed just jack up the van deflate the bags slide the on the springs and run your air lines.
https://www.etrailer.com/Vehic...ehicleid=20141113073

Or hollow rubber spring inserts $200 and much more involved install as the springs actually have to come out and be reinstalled.
https://www.etrailer.com/Vehic...ehicleid=20141014485

Both kits get great reviews but no mention of which is better or can I find an actual comparison of the two systems.

Will pull my 4wheeler and utility trailer occasionally but will be traveling with 4 adults 3 kids and all our stuff. Have a roof mount cargo carrier but depending upon the trip will have a hitch mounted bike rack or a hitch mounted cargo carrier so I need to mitigate the squat.

I really like the price of the airbags, ease of installation, and adjustability though I plan on having this van for 10 plus years I am not sure how durable the kit is compared to the kit with the rubber inserts.
But like anything I'll pay more and do the harder install if the results are worth it.

Anyone have experience with these sorts of rear spring enhancements?


————————————————
The world's not perfect, but it's not that bad.
If we got each other, and that's all we have.
I will be your brother, and I'll hold your hand.
You should know I'll be there for you!
April 28, 2017, 06:47 PM
Jaywendland1981
Yep I have installed a bunch of the airbag systems. I have also replaced a bunch of popped bags due to overloading and over inflating the bags. If you are careful you can avoid popping bags but a really good bump with a load will still pop them. The rubber may be a better choice but I have no experience with them.


There will be whores, tits and sex.
April 28, 2017, 06:51 PM
oldbill123
Might check the vehicle weight capacity and tire ratings. Sounds like it may be close to limit
April 28, 2017, 06:53 PM
Orguss
I'm just wondering how often you'd be at max load.



"I'm yet another resource-consuming kid in an overpopulated planet raised to an alarming extent by Hollywood and Madison Avenue, poised with my cynical and alienated peers to take over the world when you're old and weak!" - Calvin, "Calvin & Hobbes"
April 28, 2017, 06:58 PM
phydough
Those are some real cool wheels.

I can't be helpful otherwise, I know nothing about family truckster suspension. I would lean toward airbags though. The rubber inserts will cause it to ride rough when empty.

You were talking about lowering it anyway. Just leave it loaded up all the time. It'll have that weird Cali lean though.

Nice wheels.
April 28, 2017, 07:01 PM
cas
"Back in my day" Wink we'd put on air shocks.


_____________________________________________________
Sliced bread, the greatest thing since the 1911.

April 28, 2017, 07:15 PM
Black92LX
quote:
Originally posted by Orguss:
I'm just wondering how often you'd be at max load.


Had it less than 2 months and have already squatted it 3 times. It does not take much. Have a 12 hour drive to Florida towards the end of the year with 4 adults, 3 kids, and all the stuff to go along with it.

I have not installed my hitch yet so I am not sure if my 4wheeler on the trailer will squat it or not.


————————————————
The world's not perfect, but it's not that bad.
If we got each other, and that's all we have.
I will be your brother, and I'll hold your hand.
You should know I'll be there for you!
April 28, 2017, 07:19 PM
Black92LX
quote:
Originally posted by Jaywendland1981:
Yep I have installed a bunch of the airbag systems. I have also replaced a bunch of popped bags due to overloading and over inflating the bags. If you are careful you can avoid popping bags but a really good bump with a load will still pop them. The rubber may be a better choice but I have no experience with them.


My reading most people have found 25lbs to be ideal when loaded and 10lbs when not. Max is 35lbs so presuming 25lbs should be enough room for bumps.
Plus it runs a single valve so air would transfer to the opposite bag so unless you hit a pretty large bump with both sides one should be pretty good.


————————————————
The world's not perfect, but it's not that bad.
If we got each other, and that's all we have.
I will be your brother, and I'll hold your hand.
You should know I'll be there for you!
April 28, 2017, 07:36 PM
PHPaul
My take:

Airbags are adjustable. Rubber spacers are not. If you use the spacers the ride will be noticeably stiffer at normal loadings and there won't be a thing you can do about it.

JMHO, YMMV.




Be careful when following the masses. Sometimes the M is silent.
April 28, 2017, 07:40 PM
zoom6zoom
quote:
Had it less than 2 months and have already squatted it 3 times.

Check to see if the correct spec shocks were installed in the first place?




I have my own style of humor. I call it Snarkasm.
April 28, 2017, 07:56 PM
Black92LX
quote:
Originally posted by zoom6zoom:
quote:
Had it less than 2 months and have already squatted it 3 times.

Check to see if the correct spec shocks were installed in the first place?


They are OEM. The squat is a very common thing in the Sienna just like it is with many pickup trucks just at different weight loads.


————————————————
The world's not perfect, but it's not that bad.
If we got each other, and that's all we have.
I will be your brother, and I'll hold your hand.
You should know I'll be there for you!
April 28, 2017, 08:04 PM
Jaywendland1981
The rubber inserts wont hurt ride quality. They only make contact after the rear end has squatted a few inches.


There will be whores, tits and sex.
April 28, 2017, 08:11 PM
MooneyP226
From what I have found, your base payload without the towing package is a mere 1380 pounds. Your towing max without the towing package (since there's no hitch on it I'm guessing it is not equipped correctly for max towing) is 1200 pounds. 30% or so of your trailer weight, with a normal ball hitch (non-weight-equalizing) will be directly taken from that payload.

Using an average of 160# per adult (may be a bit heavy, may be a bit light- input your own figures Wink ) x4 os 640#

3 kids at 80?# = 240

There's 880 pounds of your max 1380.

Now, add fuel and other fluids (often the total capacity available is measured using a dry tare)

Add up weight of cargo bag, added accessories such as hitch, hitch carrier, electronics, etc.

With a max tow weight of 1200, assuming your trailer os maxed, that's 360# of tongue weight.

880 for people + 360 for trailer tongue = 1220 of 1380

You have 160 pounds capacity for all your motor fluids, and people stuff.

With loaded hitch carrier INSTEAD of trailer, at max of, say, 350# leaves you 10# extra. Your actual tongue capacity may be much less if the van is a unibody. It may be 10% of the vehicle's towing capacity (1200#), so INCLUDING the trailer tongue weight, you can only put 120# force on the hitch without risking it tearing free (think worst case scenario trying to avoid a wreck) If that is true, your actual towing capacity could be much, much less than 1200. Without a weight distributing setup it could be ~ 400#. Trailer AND load.

Your hitch carrier, if that is true, is limited to the same 120# as it is a direct load, including the weight of the carrier and pin.

I calculate loads daily while driving a truck for a living.

You most likely do not have as much capacity as you think you do to stay within the parameters of the vehicle's design or electronic safety programming. You already know your suspension is being stressed. Brakes, rims, tires, and suspension parts all have design limits too, as you know.


IIRC from my RVing days, there are several states along the Eastern part of the country that will stop and inspect your load much like they do to us truckers.

Your load calculation should be along the lines of:

Capacity: 1380

Minus:

Fuel and other liquids (gas is 6 pounds per gallon)

Permanently added equipment

Added equipment (temp., ie hitch carrier, roof bag, etc)

Weight of humans

Weight of humans' belongings

Pets(?)

Trailer tongue weight.


If you get below "0" you are trying to move more than it is rated for.

I had to buy a 3/4 ton truck when I was got a new camper back in the day because my then current and otherwise totally fine truck wasn't rated for the load. Those were fun times, calculating Gross Vehicle Weight for trailer, GVW for truck, and GCombinedVW for the combo.

At least your wheels are already awesome though- so you won't have to recalculate for the added weight difference of heavier rims since added rum size means more weight gained than tire weight (in sidewall weight) lost, not to mention the additional unsprung and rotationa weigt and forces being applied to your steering and braking systems. Wink

ETA: If you still wanna take all your stuff and everyone else's, I'd go airbags. Heavy trucks use them for a reason- ride and adjustability. And keep your load inside the wheelbase as much as possible- leverage and all, esp when you take your trailer.




Clarior Hinc Honos

BSA Dad, Cheer Dad
April 28, 2017, 08:29 PM
cparktd
I'd try the air bags, cheap enough. Would you add an onboard compressor? By the time you wear them out you will know if worth it to replace.

I bet either could easily overwhelm the dampening power of your shocks, making it a bouncy ride.



Endeavor to persevere.
April 28, 2017, 08:32 PM
doublesharp
I've had Timbren's (used to be called load levelers) on a couple of 1/2 ton pickups and they really help balance a load. I towed a trailer with a tractor/bushhog and it made my 1/2 ton's nose point to the sky. The Timbren's leveled it out but weren't noticeable when unloaded. Highly recommend Timbrens. AW Dukes in Louisville sold and installed mine.


________________________
God spelled backwards is dog
April 28, 2017, 09:14 PM
hrcjon
air bags.


“So in war, the way is to avoid what is strong, and strike at what is weak.”
April 28, 2017, 10:33 PM
reflex/deflex 64
I would go with airbags, to include the onboard air compressor. Maybe not the most premium system but not the bottom of the line. Firestone and Air Lift offer systems for trucks, maybe fewer problems?

I'm quite interested in the rubber blocks though, as I do appreciate fewer complications if it offers a comparable result.


----------The weather is here I wish you were beautiful----------
April 29, 2017, 12:53 AM
41
I would look at putting heavier springs versus the airbags which can be a safety problem.

Maybe that have a towing option which has heavier springs.


41
April 29, 2017, 02:10 AM
Gibb
My Nissan Pathfinder suffers the same issue. The easiest solution was the airbags. Just remember to keep the fill lines separate, from what I understand is that if you try to run both bags of the same line you can overload one side causing a blowout. That's usually the number one cause for failed bags, at least it is from the comments I've read on my vehicles forum.




I shall respect you until you open your mouth, from that point on, you must earn it yourself.
April 29, 2017, 04:58 AM
hudr
I had airbags on a 1-ton Chevy years ago. I liked them. Unloaded, at about 10psi, they took the "jounce" out of the rear suspension. Loaded, and at about 25-30psi, they really smoothed things out and kept the truck level.

Also, think about what MooneyP226 posted. I was in the trucking industry a long time as well. Most folks don't think about "capacity" and GVWR in terms of "all their stuff" AND women, dogs, and kids.

But I'm like you, I can't stand a squatted vehicle, loaded or not.