AHC Weight Capacity

[hkeller]

OK. My AHC now works fabulously, with one possible expection. When I have the rig full loaded with gear and a hitch packer on with another 250 lbs or so on it, it will not raise into high mode. This is a problem, as I am normally only that loaded when going off road. I can raise it into high, load it and then it will stay in, but, of course, when I pull out onto the road, it returns to normal and then won't raise when I get to a trailhead.

I was thinking it was the leverage of the hitchpacker, compounding the perceived weight. As such, I thought about moving to a roof rack. However, before I make that investment, I thought I would get your input. I like the hotch packer, as everything is easy to get to and I can remove it before doing any of the more technical trails. Plus it keeps the center of gravity lower.

Anybody have a similar situation? I've probably got 800 lbs in the vehcile and another 250 on the hitch packer when this happens.

Thanks in advance.

 

[hoser]

The AHC system has a capacity of 1250lbs in stock configuration. The springs/T-bars take a portion of the weight and the AHC takes a portion of the weight. I suspect, AHC in HI mode will make for less load capacity as the AHC part is taking on additional weight.

Since you are only carrying heavy weight occasionally, I'd say go with some airlift airbags for $90. If they ever fail, you won't be left stranded (though you might have to dump some weight=). If you are carrying heavy weight all the time, I'd go to stiffer coils, airbags that replace the coils or scrap the AHC system altogether.

 

[calbo]

Possible workaround: before hitting the trailhead, use your trusty old hi-lift to jack up the rear a bit. Then activate the AHC and catch the hi-lift before it falls and hits your truck.

 

[Waggoner5]

Or put stock 80 series springs under the rear for extra capacity. I did this on a customers truck and had great results.

 

[ChuckB]

Sounds about right, I had 20+ 45 lb bags (~900lb) of rock in my lx and it would not self-level.

 

[Dandon]

Sounds about right, I had 20+ 45 lb bags (~900lb) of rock in my lx and it would not self-level.

Chuck, I'm afraid you've misunderstood the concept of "rockcrawling"

Now seriously, this also happend to me once, and I drove 700 km on low position. I think airbags are a good option since they can be easily adjusted to diffeent load conditions. OTOH, for frequent offroad use with heavy load, the stronger springs seems to be a toguer solution.

 

[dinibili]

Since you are only carrying heavy weight occasionally, I'd say go with some airlift airbags for $90. If they ever fail, you won't be left stranded (though you might have to dump some weight=). If you are carrying heavy weight all the time, I'd go to stiffer coils, airbags that replace the coils or scrap the AHC system altogether.

Hoser

I am not convinced that addingf air cells to the rear coils will help him lift to the high. My understanding is that these "cells" are set at a height such that they sit on the axle at normal height to stop the vehicle sagging with extra load. Putting more air in them does not make them longer. When you try to lift with AHC with the vehicle fully loaded, the "cells" will lift off the axles and be no use at all. I am aware of a bloke here that did this with a new cruiser with AHC and it was a total waste of time, I suspect, for the above reason.

Donald (on the Rock)

 

[Zimm]

Hoser

I am not convinced that addingf air cells to the rear coils will help him lift to the high. My understanding is that these "cells" are set at a height such that they sit on the axle at normal height to stop the vehicle sagging with extra load. Putting more air in them does not make them longer. When you try to lift with AHC with the vehicle fully loaded, the "cells" will lift off the axles and be no use at all. I am aware of a bloke here that did this with a new cruiser with AHC and it was a total waste of time, I suspect, for the above reason.

Donald (on the Rock)

the bag will increase the static load capability of the suspension. the ahc is in addition to this. i dont see why it wouldnt work if the proper length bags are installed.

 

[hoser]

Dinibili, that's a good point. There's a chance Airlift makes a 2" taller cell of the same diameter. Though not so sure if there would be problems running the bags when the suspension is in "N" mode, 2" lower. Maybe a cell 1" taller would be a good compromise.

 

[hkeller]

Thanks for all the input. Why would I use stock springs from and 80 and opposed to 100 LC?

 

[hoser]

I don't know the exact spring rates but in order from lowest spring rate to highest spring rate, it goes:
AHC 100
OEM 80
OEM 100
Most anything OME is even higher/taller.

Keep in mind the OEM 80 springs are uneven in height and you might want to get two of the shorter springs (PS) for less lift or two of the longer springs for more lift, or use trim packers on one side. In any case, you'll want to adjust the AHC sensor to get optimal balance (shock damping).

The OEM 80 springs are significantly "stiffer" than the AHC springs. I'm not so sure the ride would be acceptable on a stock weight rig. Maybe Christo or Wagoner would know. I'm using the 80 series springs but also have additional weight.

 

[uHu]

If you don't want stiffer springs, it would probably help with just new springs, as your coil springs (and TBs) are 7 yrs old, they don't carry the same weight anymore, leaving more work for the AHC.

Reasons for getting stiffer or longer springs could be:
- heavier rig than original
- lift
- you want larger load carrying capability and don't care about not beeing able to get into the LO setting.

If you are not in a position to try out different springs, you should really find out the spring rates of the different offers.
Think I saw a list somewhere showing some OME springs with approx same rate as OEM 80 springs?

Keep us posted.

 

[hkeller]

Well, as I am below the 1250 lbs limit of the system (even accounting for age of the springs, I am probably still below the systems limits in terms of total weight) I may simply move away from the hitchpacker to a roof rack. The only thing that causing me to exeed the systems limits, as far as I can tell, is the leverage the hitch packer has on the vehicle. By moving to a roof rack, the leverage is removed and the perceived weight should be within the limits of the system.

Until I take over this vehicle as my own, I want to maintain the plush ride for my wife. So, a non-spring change option is worth me pursuing.

Now, which rack is an entirely different question. I may look generally at my gear and see where I can limit weight. If I go with an AL rack and find low weight alternatives for my gear, like taking 16 inch chain saw as opposed to 26 inch one on camping trips, I can probably solve this problem inexpensively. Also, I have not been removing the thrid row seat, which is an easy was to ditch a hundred pounds.

Any thoughts on that idea. Thanks,

 

[calbo]

hooo boy you're gonna take a lot of flak by mentioning that chain saw

 

[hkeller]

What is wrong with taking a chainsaw on a camping trip? It's legal in the national forest in this area to cut any downed/dead trees. You can't cut anything standing, even dead trees, unless, of course, you have a foresting permit. Plus, in the winter, you often need to cut tree that are blocking the public road in the mountains. If I don't do it, the county will. However, I welcome any input, if this is not considered low impact.

The point was, there is probably a lot I can do to reduce the weight I carry in my 100, just like I reduce the weight I carry in my backpack on long trips. Like taking aluminum, not steel chairs. Bring the .357, in lieu of the 12 guage. Bring an extra strap in lieu of a chain.

 

[calbo]

What is wrong with taking a chainsaw on a camping trip? ... I reduce the weight I carry in my backpack on long trips. Like taking aluminum, not steel chairs... .

I bring an axe.
Also doubles as a... umm, a bottle opener

 

[e9999]

some would argue that there is something fundamentally wrong about not getting the stronger springs so your wife can continue liking the ride so you can't drive the 100....

 

[hkeller]

e9999:

No cr*p; you are so right. I totally do not wear the pants around here. I try, but it is a huge!!! debate. Her folks are, as they say, LOADED, and they basically bought her the 100. So, I sit and wait until mother-in-law, says, "Sweety (not me) you need a newer safer car for you and the kids; let your hubby drive the beater." Funny thing is, I am pretty successfuly at what I do, but I can't hold a candle to, "You need a new car, we'll buy you an LX470 with cash, they're supposed to be safe, honey."

Get my drift?

 

[hkeller]

PS: The dude with the Bud Light (wife's brand) and the ax is both terrifying and lovable at the same time!

 

[hkeller]

Hey: How come my last two post are both number 162?!^#*^* What gives mod?