Rear suspension...?

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AlreadyGone

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Yep, me again.  :p Same astro and 6x12' CT. I've been wondering about the rear suspension and towing the trailer.

The leaf springs have 3 leafs, and the shocks are yellow, no labels that I can find, but stamped: Made in the USA P364H. I cannot seem to locate that part number on line, so I really do not know what brand they are, etc.

The hitch is a class 3 Reese with a Max tongue weight (there are 2 listed on the sticker) WD 500-600 lbs

The tongue weights for single axle 6x12' trailers are generally under 200lbs.

I weight just over 200lbs and standing on the rear bumper causes the rear end to drop ~1"....1.5" max.

Being relatively new to towing, I'm wondering if I need to have much/any concern about beefing up the rear suspension. I realize that the trailer needs to be loaded properly, so if that is the case...how do things sound to you as I describe?
 
AlreadyGone said:
Being relatively new to towing, I'm wondering if I need to have much/any concern about beefing up the rear suspension. I realize that the trailer needs to be loaded properly, so if that is the case...how do things sound to you as I describe?
A friend of mine that is well versed on hauling everything from big trailers with an 18 wheeler, to smaller stuff with his pickup uses air bags in the rear, and has hauled a 31' trailer with it. For hauling a travel trailer on a regular basis, he also recommends using an equalizer hitch.
 
The tongue weight of a cargo trailer will vary depending on what you have loaded in the trailer and, even more importantly, WHERE you have it loaded. If you load all sorts of heavy items forward of the axle(s) then your tongue weight will increase. Load those heavy items behind the axle(s) and you can reduce tongue weight. Care with that though, as you may go negative tongue weight and the trailer points it's tongue up into the air and you get in a whole lot of trouble.

Basically, having some weight that is crunching the rear suspension is normal. All you are looking for is, 1) Not exceeding the hitch capacity, and 2) not crushing your rear suspension so much that your vehicle "squats" (rear down, nose in the air). A slight squat is OK for short distances, but I wouldnt take it on the highway long distance. You want your vehicle and trailer to all be nice and horizontal.
 
AlreadyGone said:
The hitch is a class 3 Reese with a Max tongue weight (there are 2 listed on the sticker) WD 500-600 lbs
You may already know this, but for the benefit of others who come along and read this thread . . .
The reason receivers have two tongue weight listings is that one is for a simple hitch, and the heavier one is for using a weight distributing hitch.
With a simple hitch, all of the tongue weight is carried by the rear axle, and in fact, the leverage it exerts on the vehicle will actually offset some of the weight on the front axle.
With a weight distributing hitch, when properly adjusted, both the front and rear axle carry equal amounts of the tongue weight.
 
If the load is causing your rear to squat a lot, you have a few easy options

1) Load adjusting shocks can help carry some of that load. I have a pair of these on my van, and they helped a bit, but not a lot. Great to do if you are needing to change your shocks anyway.
2) Leaf spring helpers, work by basically adding an additional spring to your leaf spring setup. I added these as well, which helped a lot more. Probably your best bet for a quick, bolt on, fix without breaking the bank.
3) Lastly, Air bags. I installed some of these on the truck that tows our Airstream since the tongue weight is so high it was causing massive squatting. At $300+ they are pricey, but they are the end-all fix. You have no more worries once they are on and inflated. However, you may want to deflate them when not towing as they will make your unloaded ride extremely stiff and possibly bouncy to the point of being a hazard at speed. Once loaded, this no longer poses a problem.
 
Good info here, and I definitely appreciate ya'll helping me understand this. I don't mind modifying/upgrading/investing in this van where needed, but, of course, I'm trying to avoid that if practical.

1) So, generally speaking, if there's too much squat...then I can or should be able to shift a bit more weight to the rear of the trailer, correct?

2) The tongue weight listed for the trailer is what? Is that the tongue weight of the trailer empty/without any cargo? If yes, then I would seek about 10-15% gross trailer weight on the tongue? So, if the trailer weighed out at 3,500lbs gross...I would be seeking roughly 350lbs tongue weight?
 
ok does the van sit level without the trailer hooked up or does it sag in the rear? if it sags without a trailer your springs need work. basically your van should sit level. then hook up the loaded trailer if it sags now the best alternative is air bags or more leafs added. I like the air bags because when the trailer is off you can let some air out and regain your original ride height. DO NOT use the shocks for compensating ride height weather coil over or air shocks. shock mounts where never design to carry the weight. highdesertranger
 
second on no air/spring shocks
let the shocks do their job and let the springs do theirs
overload leaf springs would be the cheapest,quickest
 
tongue weight listed by the seller is empty tongue weight, you will need to give soem thought to how you load it, you want 10-15% of the total weight on the tongue, more is better within that range, so say 3500lb total weight, 350 -385 tongue weight, I would look for 385, for less sway, with trailer set level
then make sure it sits level when hitched, and the van sits level, too
 
highdesertranger said:
ok does the van sit level without the trailer hooked up or does it sag in the rear?  if it sags without a trailer your springs need work.  basically your van should sit level. then hook up the loaded trailer if it sags now the best alternative is air bags or more leafs added.  I like the air bags because when the trailer is off you can let some air out and regain your original ride height.  DO NOT use the shocks for compensating ride height weather coil over or air shocks.  shock mounts where never design to carry the weight.  highdesertranger

It sits fine now, and seems stout. There doesn't seem to be any issue, but I'm not sure and trying to understand what to expect. How much does a weight distributing hitch help...and do I need 1? I think: Yes, but I really don't know.

2000 Astro LS AWD
Vortec 4.3L
Rear: 3.42
GVW: 4160
Payload: 1600

6x12 Trailer
Single axle
Brakes if I order, Probably not if bought used.
GW: 3000Lbs, unless I order with 3500 or 5200 lbs axle.
Expected total trailer weight: ~3000lbs

Cargo weight in the van needs to be considered the same as towing weight per owner's manual.
 
My friend added airbags to his 96 Astro for load support. The bags used are different than the Firestone ride rite bags on my full size van. I think his only add 2000 pounds of extra support, instead of the 5000Lbs of the full size bags.

And no this does not mean the vehicle is then safe to carry that much extra weight. Beefier rear suspension alone does not increase the GVWR. His astro was sagging dangerously when loaded down with headlamps not hitting the road.

I generally inflate my airbags to keep the same distance between top of tire and wheel well on all 4 corners, as this seems to make the van handle the best. The PSI depends on how much weight I am carrying, but usually I have 10 more PSI drivers side.

I'd recommend getting the burliest tow hitch offered for your vehicle.
 
SternWake said:
Beefier rear suspension alone does not increase the GVWR. 

Actually, NOTHING you add or change on your vehicle legally changes the vehicles GVWR.  That's assigned by the manufacturer when they build it.

Get into an accident with too heavy a trailer and it won't matter what changes you made, you're going to have legal problems.
 
SternWake said:
My friend added airbags to his 96 Astro for load support.  The bags used are different than the Firestone ride rite bags on my full size van.  I think his only add 2000 pounds of extra support, instead of the 5000Lbs of the full size bags.

And no this does not mean the vehicle is then safe to carry that much extra weight.  Beefier rear suspension alone does not increase the GVWR.  His astro was sagging dangerously when loaded down with headlamps not hitting the road.

I generally inflate my airbags to keep the same distance between top of tire and wheel well on all 4 corners, as this seems to make the van handle the best.  The PSI depends on how much weight I am carrying, but usually I have 10 more PSI drivers side.

I'd recommend getting the burliest tow hitch offered for your vehicle.

Well, it's already got a Reese Class lll on it. I was asking about the rest of it:

Weight Distribution Hitch

But this is what I am trying to sort out...whether I need things like airbags...or should need them. Ya'll know a lot more about all of this than I do, so I just hope that I can get info that leads me in the right direction. I really don't want to be loaded up, ready to go, just to have to wait around to get some off-brand airbags (or whatever) from some local shop.

As before, I am just over 200Lbs. I just went out with a tape measure. Standing on the rear bumper...it dropped 7/8" So, If I am realistically looking at a max tongue weight of 385lbs. I think I'm good, but I don't really know...that's why I'm checking with you guys.

I'm not against airbags, weight-distributing hitch, sway control, etc...I'm just wanting to be safe and spend as little money as possible...yet still be in the safe-zone. And, I am very open to the idea of leaving here with the minimum (so to speak) and doing long-term upgrades, improvements, etc after getting out of here. But, that will involve a roughly 2K mile journey before I stop long enough to de-stress and settle anywhere for any length of time<---more than a few days.
 
Ok, so with airbags I don't have to buy a compressor, right? I can just set them up to fill and release air like I would with air shocks, correct?
 
that is correct, but having an on board air compressor is so nice. highdesertranger
 
I have to agree with HDR - it is ever so nice!

After having to borrow one (thanks Larry.. :D ) after the RTR I bought my own - $65.00 from W/M - it's a Slime heavy duty that does up to 150 psi and even came with an additional length of hose for those hard to reach places and all the extra tips for blowing up beach toys etc.

Since working air hoses are getting harder and harder to come by and most places are now charging for air...sigh...having a compressor on board just makes sense.
 
Airbag's adjustability is nice for changing loads. i use mine to 'level' van with 100PSI curbside bag and 0PSI street side when stealthing. I put schrader valves inside van and can change pressure from within.

They can lose PSI over time so having a method to fill them, even if a hand pump, is better than havig to rely on a coin operated gas station machine.

Air shocks, well the shock mounting hardware is not designed to support the weight of the vehicle. Asking them to do so might damage Axle or frame where they mount, or might be 'just fine'. I would not ever employ add load support shocks to my own vehicle.
 
highdesertranger said:
that is correct,  but having an on board air compressor is so nice.  highdesertranger

SternWake said:
Airbag's adjustability is nice for changing loads.  i use mine to 'level' van with 100PSI curbside bag and 0PSI street side when stealthing.  I put schrader valves inside van and can change pressure from within.

They can lose PSI over time so having a method to fill them, even if a hand pump, is better than havig to rely on a coin operated gas station machine.

Air shocks, well the shock mounting hardware is not designed to support the weight of the vehicle.  Asking them to do so might damage Axle or frame where they mount, or might be 'just fine'.  I would not ever employ add load support  shocks to my own vehicle.

Ok, but considering the following do they seem like more of a necessity or a luxury:

As before, I am just over 200Lbs. I just went out with a tape measure. Standing on the rear bumper...it dropped 7/8" So, If I am realistically looking at a max tongue weight of 385lbs. I think I'm good, but I don't really know...that's why I'm checking with you guys.
 
an astro pulling a 6x12,eww,i dont like the idea of an astro pulling anything but you keep it light and drive mellow you should be o.k.
i would be more concerned about braking then anything else,i like to balance the trailer out so it has a touch of tongue weight so the trailer carries the load and the tow vehicle pulls and stops the load,it is absolutely a butt puckering moment when your trailer is pushing you down a hill
 
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