GVWR and RGAWR for towing vehicle
I apologise for posting this twice but as a new member I am still figuring out the Forum.
In August, we are travelling to outback Queensland including Birdsville and I have been investigating the weight of my Patriot SEL Outback caravan and MY2013 Jeep Grand Cherokee fully laden for the trip.
A couple of weeks ago, I packed my Jeep and Caravan as if I was heading off to Birdsville with additional water, fuel spare tyres etc and put both the Jeep and the Caravan over a Public Weighbridge.
Here are the figures:
JEEP GRAND CHEROKEE and SUNLAND PATRIOT SE-L CARAVAN
Gross Combination Vehicle Mass (GCVM) 6240 6,449
Caravan Gross Trailer Mass (GTM) 3,020 3,324
Caravan Aggregate Trailer Mass (ATM) 3,340 3,500
Car Gross Vehicle Mass(GVM) 2,940 2,949
Tow ball weight 320 350
JEEP GRAND CHEROKEE From Handbook
Actual Allowance Variance
Gross Vehicle Weight Rating (GVWR) inc ball weight 3,260 2,949 311
Front - Gross Axle Weight Rating (Front GAWR) 1300 1,452 -152
Rear - Gross Axle Weight Rating (Rear GAWR) 1,960 1,678 282
Whilst initially both the car and caravan (independently) are under their respective ATM and GVM, it looks like there are issues with the Jeep GVWR and Rear GAWR when the caravan is attached.
I understand the tow ball weight needs to also be taken into consideration in the calculations of the Gross Vehicle Weight Rating (GVWR) – the Jeep GVM at 2940 + tow ball weight at 320 = 3260kg which is over the listed GVWR in the Jeep owner’s manual. I can drop the tow ball weight back to 280 by removing 40 litres of water stored in jerry cans on the front drawbar.
This puts the GVWR about 300kg over in total and the Rear Gross Axle Weight Rating (RGAWR) over by an amount of 282kg.
Have I calculated this correctly or have I misinterpreted the figures?
What are the options available?
I have looked at what I have in the Jeep to possibly reduce the payload of the Jeep but I cannot reduce it down by anywhere near 300kg – it just won’t work. I have a long range fuel tank that contains 75 litres of fuel, a cargo area including a 2nd battery and fridge, and I am carrying a second spare tyre for the jeep. All of these items I feel are necessary for where we are going.
Is there a way that strengthening the rear suspension and having it re-certified by say another 250-300kg would overcome the issue?
I would prefer not to use a weight distribution hitch due to my D035 off road hitch and some of the places I am travelling. I assume that using a WDH might move some of the weight on the rear axle to the front axle (let’s say 140kg) however the rear axle will still be some 150-170kg over.
Are there any other options that can be considered (apart from getting another vehicle which is not really an option)?
I look forward to your input and thanks for your assistance.