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Have Cummins, Will tow.
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Trailer is not an option.

I did some comparing on the Cars.com site.

A 1998 Grand Cherokee with similar type suspension is rated for 1150 lbs. load. Uses the same Dana 30/35 axles and coil spring suspension. Difference from the Wrangler is tires.
There is more than just the "similar" suspension. Fame, brakes and steering are all factored into that. Plus your lift adds weight so that takes away from your GVW. Do you plan on upgrading your brakes and steering when you add all that weight? How tall will this tank be? I get the fact it will be foam but that still raises the COG, so will you factor that in? As for the CJ you mentioned was it a dual rear wheel? Almost every Fire CJ I've seen was a DRW. Will your Jeep hold 1000 lbs in the back seat, Yes, Will it do it safley? NO!
 

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Discussion Starter · #22 ·
You know how much room you need for 50 gals of water.
Water=8.2lbs
7.3gals= per cubic foot
So you will need about 7 sqf and the back plate of a tj is only like 6sqf
A gallon is 231 cu in, x 50 gallons = 11550 cu in. With a footprint of 35 in x 35 in (the usable area of the cargo area, and the footprint of the aluminum tank I will build) leaves a height of only 9.43 in. As for volume, it will fit easily. Also, the COG of the tank is half the height or 4.7 in. With 50 gallons @ 8.2 Lbs/gal gives 410 lbs. at 4.7 in gives a torque moment of 160 ft-lbs. That of two 200 lb passengers sitting in the rear seat (weighing 30 lbs) with a COG of 18" (measured in my TJ) gives a torque moment of 645 ft-lb. The body roll through a turn with two rear passengers is well over three times that with the water tank. The only issue is the additional weight of the pump, frame, hose, jaws and tools. I estimated that equipment at 400 lbs. With that mounted on top of the tank would still not raise the COG above the top of the tank, but I'll use it for the moment calculation. At 810 lb at 9.43 in equals a torque moment of 637 ft-lbs, less than that with two passengers.

There is more than just the "similar" suspension. Fame, brakes and steering are all factored into that. Plus your lift adds weight so that takes away from your GVW. Do you plan on upgrading your brakes and steering when you add all that weight? How tall will this tank be? I get the fact it will be foam but that still raises the COG, so will you factor that in? As for the CJ you mentioned was it a dual rear wheel? Almost every Fire CJ I've seen was a DRW. Will your Jeep hold 1000 lbs in the back seat, Yes, Will it do it safley? NO!
Front brakes (calipers, rotors, and pads) on the Cherokee are the same on the TJ. The Rubicon Dana 44s also have rear disc brakes where the Cherokee only has drums. I have upgraded to a beefier tie rod and link along with heavier dampener, and adjustable track bars. The adjustable upper and lower links are solid 1 1/2" steel (not tubing) with poly bushings where both the Cherokee and TJ are stamped steel with rubber. The fire department CJ sold on Eday did not have duals. Tires would be a concern if the payload were to be carried at speed for extended time, but that is not the case here.

Most of the weights for payload etc are for safety on the road.

If you aren't using this jeep on the road, put some airbags in it to control the weight and load her up. The TJ has a pretty strong frame if it isn't rusted, axles are defiantly stronger than rated payload of the jeep. Just keep in mind that weight in the jeep is going to seriously effect handling at speed and braking.

Assuming that the jeep is only used on the track you could put a decent sided tank in front of the grill attached to the front bumper. But you may need to put in heavier springs or air bags in the front for the weight.
The TJ is my daily driver, rock crawler, EV vehicle. I will be removing the CFR equipment between races. It is not in our budget to purchase another vehicle. I like the idea of adding air bags. I can then remove them when I take out the foam system. Also, it won't be driven on the street with water in the tank. The tank will be filled and emptied at the track.
 

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Have Cummins, Will tow.
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Damn infedels, don't get shown up by the dirka dirka...thinking it might be a toyota, but you get the idea.
That doesnt count. I've seen 6 people on a BICYCLE! A Camry on top of a bus, A Camry in back of a Heliux (Toyatas version of a Ranger). Wasn't able to count all the sheep in the Camry. I stopped counting the RPGs, AKs RPKs and other weapons in the bed of the Heliux that had 6 guys in the bed and 4 in the cab. All this was on the same mission
 

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Pretty funny how everyone will add hundreds of pounds in lifts, cages, tires, bumpers, winch, gear and people, but if you mention running 1000 or so lbs in a jeep rated for an 800lb payload, then buses full of nuns and blind children are in peril.

I used to treat my YJ like a truck, because it was the only vehicle I had. I'm sure I had much more than 800lbs (YJ's had the same rating) in it several times between general use and weeklong desert runs.

Sounds like you have it figured out.

Jack
 

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Pretty funny how everyone will add hundreds of pounds in lifts, cages, tires, bumpers, winch, gear and people, but if you mention running 1000 or so lbs in a jeep rated for an 800lb payload, then buses full of nuns and blind children are in peril.
Who is being dramatic, eh? First off, tires are not sprung weight (unless you mean the spare). And people in this thread have already told OP to take into account items already in the Jeep for the total payload. OP asked what can be done SAFELY. That's the answer he is getting.
 

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Who is being dramatic, eh? First off, tires are not sprung weight (unless you mean the spare). And people in this thread have already told OP to take into account items already in the Jeep for the total payload. OP asked what can be done SAFELY. That's the answer he is getting.
Oh, but tires do count toward GVWR. The physics of starting, maintaining and stopping that weight is still there and must be accounted for. Also big difference between being dramatic and sarcastic... I am fluent in the second.:wave:

I'll let you decide which one I was going for.

I will still argue that he is not driving down the road at 65mph+ with this "payload." He has said that he will not be "loaded" until he is at the venue, therefore his situation is much different that what Jeep "rated" the jeep to safely carry. Their rating is for normal operations on a highway at speed day in and day out. A couple of hours a day for two days (at most) while sitting for the majority of that time isn't to be considered normal operation.

All I'm saying is that people routinely overload the crap out of their jeeps (they have been doing it since the inception of a jeep) and using them for many years in that capacity. Buses of nuns and blind children notwithstanding...:D

Jack
 

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Then a tj is not the right vehicle for the job.
x2000

If you are using this as a QRV you want something that will not just handle the weight, But Handle the weight as well as get you there as quick as possible. The TJ is not the vehicle for this. You dont want to be the one
that has an accident on the way to save someone. then you have a whole new situation to deal with and aren't able to save or help anyone.
 

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Trailer is not an option.

I did some comparing on the Cars.com site.

A 1998 Grand Cherokee with similar type suspension is rated for 1150 lbs. load. Uses the same Dana 30/35 axles and coil spring suspension. Difference from the Wrangler is tires.
and weight of the vehicle, and wheel base... the two vehicles re not the same
 

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Weight limit sticker should be inside the door somewhere. I think on mine it is on part of the tub on the drivers side door area but I forget.

If you have insurance for the race, through the track or whatever, they may very well do a quick bit of math if you have a wreck with the jeep.

If you tell your insurance what you do with the jeep and pay for the coverage in all the fine print will be mention of stock vehicle specifications or something.

Weight limits on a vehicle take all sorts of stuff into account. On a tj I personally think one of the big things is the wheelbase. An lj has a better towing limit for a reason, but came with the same engine and all kinds of similar stuff.

Lots of wranglers are overloaded and I am not about to say I am going to be perfect every day I own my tj.

That cj you saw on ebay may have been overloaded, or as someone mentioned was specced for that job.

Anytime I was racing, just quarter mile stuff, all damage was on me since I did not want to pay the insurance for that coverage. I never worked as a rescue crew helper but my understanding was that the race tracks insurance was very picky about making sure things were done right.

Anyway, just my experience and opinion on it.

That sticker on the vehicle means a lot and I have seen half ton trucks do the jobs of a one ton truck but that sticker can mean having insurance cover an accident or not.

In today's world I can't afford to have my insurance not cover an accident.
 

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Have Cummins, Will tow.
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12,019 Posts
Pretty funny how everyone will add hundreds of pounds in lifts, cages, tires, bumpers, winch, gear and people, but if you mention running 1000 or so lbs in a jeep rated for an 800lb payload, then buses full of nuns and blind children are in peril.

I used to treat my YJ like a truck, because it was the only vehicle I had. I'm sure I had much more than 800lbs (YJ's had the same rating) in it several times between general use and weeklong desert runs.

Sounds like you have it figured out.

Jack
Problem is he has the normal lift and armor and is adding that gear on top of that already over weight jeep

Sent from my phone so expect errors
 

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I live in Grass Lake, Michigan. Our Fire/Rescue bought and outfitted a 2009 JK Rubi for just such an operation. Here it is in action:
I have seen it go LOTS of places with that setup. I doesn't even slow down over rough terrain with it. The last time i saw it was cruising across a farmers field at 40 mph to a brush fire. The jeep they used before that was a CJ6 with the V6.
 

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I would hesitate to use my personal vehicle for any work related hauling, like someone else said, insurance will find a reason not to pay. You are using an already lifted vehicle to respond quickly to an incident on a race track, you will likely drive faster than you should, which could easily spell disaster for you and your Jeep. Something to also consider with carrying liquid is that it moves, when you go to stop the car, the water will still want to keep moving making it more difficult, plus it changes the way your car handles dramatically. If the track already has a fire response vehicle than I would think they need to be equipped to handle any fire that might happen in their venue. Your club needs to review its needs with the track to ensure they can handle incidents accordingly. Like many people have said, we all have overloaded our Jeeps or other cars at one time or another, it does not make it smart or right. Good luck to you in finding a solution!
 

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If you are at a race track, how far are you actually talking about traveling? maybe a mile at most? I guess it depends on the track but I doubt they will be doing much more than 35 - 45 mph on the way to a wreck.
 

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In a nutshell, get a different rig for this or you will be the one that needs rescueing
 
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