Can the weight police check these numbers for me?

gemsworld wrote:
I recently acquired a new TV to pull my 21' TT and I have some numbers that I would like to share with the experts here to see what they think.

The TV is a 2014 Jeep Grand Cherokee with the following specs:

6,200 lb towing capacity

6,500 lb GVWR

1,270 lb payload

4,880 lb curb weight with a full gas tank

2,540 lb front & 2340 lb rear per CAT scale

3,200 lb front & 3,700 lb rear GAWR


9,740 lb combined weight of the TV and TT, fully loaded with WDH and gas tank 1/3 full per CAT scale

2,620 lb front, 3060 lb rear & 4,060 lb TT per CAT scale

From what I gather, it seems that I'm well within the maximum limits but I'm a bit confused regarding the discrepancy between the GVWR and payload capacity based on the curb weight.

If the GVWR is 6,500 lbs and the curb weight is 4,880 lbs, logic would dictate the payload should be 1,620 lbs instead of the 1,270 factory rating. Am I missing something in the equation, or it's not unusual to have these types of discrepancies with the specs?

Your Jeep weight rating probably included a 154 pound driver on board. So it would be impossible to have a 5,000 pound curb weight and 6,500 pound GVWR and still load 1,500 pounds of cargo - with no driver on board to move the vehicle without exceeding the GVWR. Thus Jeep estimated that some of the Jeeps will have a curb weight near 5,000 pounds, and conservatively said "We can safely load 1,200 pounds and still not exceed 6,500 GVWR."

If you look closely, the WDH shifted 80 lbs to the front axle. Do you think that's adequate, or should I adjust the WHD to add more weight to the front or get rid of the 80 lbs. As it is right now, both the TV and TT are fairly leveled.

As always, I'm looking forward to hearing from the experts.

I would not try to tighten the WD hitch any more than it is. You do not need to transfer any more weight, and many who do, find that the WD bars act as a spring, and make the ride less stable than when you don't tighten it a lot.

You have plenty of extra capacity on your front and rear axles. It seems like you can calculate your hitch weight based on the increased curb weight while hitched up.

With 80 pounds transferred to your Jeep front axle, also about the same amount of hitch weight is transferred to the trailer axles too.

Did you discover the 'easy' way to attach the spring bars? By raising the hitch on the trailer a LOT, you can attach the bars with very little spring pressure on them, practically by hand pressure, not using the levers at all to lock them in place. Just make sure not to over tighten the spring bars.

Have Fun Camping!


Fred

OK so I am a Jeep Engineer....

6,200 lb towing capacity

6,500 lb GVWR

1,270 lb payload

4,880 lb curb weight with a full gas tank

2,540 lb front & 2340 lb rear per CAT scale

3,200 lb front & 3,700 lb rear GAWR


9,740 lb combined weight of the TV and TT, fully loaded with WDH and gas tank 1/3 full per CAT scale

2,620 lb front, 3060 lb rear & 4,060 lb TT per CAT scale

6,200 lb towing capacity, 1,270 lb payload - These are just marketing ratings, your vehicles actual ratings will vary.

2,540 lb front & 2340 lb rear per CAT scale - You easily meet the axle ratings.

OK so this means that your JGC weighs 4880# (2540+2340).

The GVWR is 6500 so your JGC's payload (6500-4880) capacity is 1620#

The weight of your trailer appears to be 4860 (9740-4880).

So you have left out one important rating: GCWR

What you can tow = GCWR - 4860

Assuming you meet the GCWR requirement (Please post your result) I also concur that the WDH settings look ok as is....

2,540 lb front & 2340 lb rear per CAT scale


2,620 lb front, 3060 lb rear & 4,060 lb TT per CAT scale

You have too much weight on the front axle ... You only want to restore front axle to stock and never over..

Your tongue weight seems to be 720 lbs.. thats a lot of weight for that jeep no?

And what 21 ft TT do you have that has that much weight?

gemsworld wrote:
If the GVWR is 6,500 lbs and the curb weight is 4,880 lbs, logic would dictate the payload should be 1,620 lbs instead of the 1,270 factory rating. Am I missing something in the equation, or it's not unusual to have these types of discrepancies with the specs?

This web page gives a single payload value of 1270# for all 2014 GC Limited 4x4 versions even though there are three different curb weights depending on engine choice.
It appears that the 1270# payload is for the diesel engine version which has a curb weight of 5275#.
The V6 version has a curb weight of 4875# which is very close to the 4880# you measured.
I think it is safe to say that the payload for your GC is about 6500-4880 = 1620#.
However, you should look on the TIRE AND LOADING INFORMATION sticker on the driver's door edge or pillar to see what is listed for the maximum allowable weight of occupants and cargo.

If you look closely, the WDH shifted 80 lbs to the front axle. Do you think that's adequate, or should I adjust the WHD to add more weight to the front or get rid of the 80 lbs. As it is right now, both the TV and TT are fairly leveled.

I recommend that the front axle load with TT attached and WD applied should not be greater than when unhitched.
It is not necessary to adjust the WDH to make the TV "level".
Does your GC have the automatic-leveling suspension. If so, was the auto leveling active when you were adjusting the WDH?

To properly interpret your two sets of scale measurements, you need to add about 100# to the rear axle load for the second set to account for the missing 2/3 tank of gasoline. You can assume all of this weight should be added to the rear axle.
The indicated TT weight would be (2620+3160+4060)-4880 = 4960#.

To achieve a front axle load increase of 80# and a rear axle load increase of 3160-2340 = 820# would require a tongue weight of about 1200# with about 300# being transferred to the TT's axles via the WDH.
So, either there is a problem with your scale measurements, or you have a very heavy tongue weight for a 4960# trailer -- 1200/4960 = 24%.

Ron

Thanks for all your comments.

The 720 lbs added to the rear axle also includes about 90 lbs of gear in the back of the SUV and another 55 lbs for the Equalizer WDH. I'm guessing the actual tongue weight is about 575 lbs, which seems to be about right for a TT with a 4,882 lb GVWR.

Let us know how it tows with that 5000 lb brick behind it

Yeah... Something wrong with the weights IMO....

gemsworld wrote:
The 720 lbs added to the rear axle also includes about 90 lbs of gear in the back of the SUV and another 55 lbs for the Equalizer WDH. I'm guessing the actual tongue weight is about 575 lbs, which seems to be about right for a TT with a 4,882 lb GVWR.

You cannot use only the rear axle load change to determine tongue weight -- you also must include the front axle load change.
You also cannot use the TV's axle loads when hitched with WD applied to determine the tongue weight -- you must use the axle loads with TT attached and no WD applied.

And, if you have the Equal-i-zer brand hitch, the weight probably is closer to 100# than 55#.

If you add 90+55 = 145# to the first weighing to correct for cargo and WDH weight which was not included, the TV's first GVW would have been 4880+145 = 5025#.
If you add 100# to the second weighing to correct for 2/3 tank of gasoline which was not included, the second GVW would have been 5780#.
The TV's weight, with TT attached and WD applied, would have increased by 5780-5025 = 755#.

However, that does not mean the TT's tongue weight is 755#.
In order to increase the front axle load by 80# while increasing the TV's GVW by 755#, a load of approximately 270# would need to be transferred to the TT's axles.
This means the indicated tongue weight was approximately 755+270 = 1025#.

If you want a better estimate of tongue weight, you need to re-weigh your rig.
The weight of TV occupants and cargo should be the same for all weighings.
The WDH should be in the receiver and the WD bars should be in the rear of the TV for the "TV only" measurements.

A second set of weights should be taken with the TT attached and the WD bars in place, but with no load applied to the WD bars.

The sum of the TV's axle loads from the second weighing minus the sum from the first weighing will be equal to the TT's tongue weight for that loading condition.

Ron

Can you be specific about the numbers you feel are wrong? The numbers I used came from a commercial scale. I'm sitting here looking at the weight tickets.

repost all you weight tickets, weights please..

Post what tt you have also....

Thanks