Parkliner Weight Distribution Kit

[Jon in AZ]

Originally Posted by MaryNJWildlife

...Murano specs:
Front curb weight = 2345
Rear curb weight = 1635
Total curb weight = 3980 (after reading, I learned that this includes fuel)
Max payload = 1195
GVWR = 5311 (not sure why this is not equal to the curbweight + payload)
Maximum tow capacity = 3500
GCWR (by my calculation) = 3980+1195+3500 = 8675
...

I doubt that your GCWR is the total of the curb weight plus the payload plus the maximum trailer weight. It doesn't work that way. It's probably less than that, maybe quite a bit less. For one thing, part of the trailer weight (typically around 10-15%) is carried on the hitch and reduces available payload. For another, tow ratings assume two people and minimal additional payload; more than that in people or equivalent cargo reduces the maximum trailer weight.

There are four primary weight ratings supplied by the vehicle manufacturer:
GVWR: maximum recommended weight of the vehicle and everything in it, including any trailer weight carried on the hitch (tongue weight)
GAWR (front and rear): maximum recommended weight carried by each axle; the rear axle is the one to watch
GCWR: maximum recommended total weight of vehicle, trailer, and everything in both

Payload, tow rating, and tongue weight rating are derived from the above ratings, and there is give and take among them.

The trailer also has a GVWR and a GAWR.

In addition, tires have weight ratings. Generally the combined rating of both tires on an axle is more than the GAWR to allow for a little left-right imbalance. However severe left-right imbalance can overload a tire on one side without overloading the whole axle.

To find out if WDH is indicated, you should load the trailer and vehicle (people and cargo) as you normally do and weigh each axle. If the vehicle's rear axle approaches or exceeds the GAWR, adding WDH will transfer weight from the vehicle's rear axle to the vehicle's front axle AND to the trailer's axle.

And as if that isn't enough to give us all a headache, there is frontal area to consider. Tow ratings are tested with low profile box trailers. The added height and width of a typical travel trailer puts additional strain on the drivetrain at highway speeds or when towing into a headwind, partly mitigated by the rounded shape of many molded trailers. Some manufacturers address the frontal area issue by slapping on a limit; many ignore it. But it's a good reason to stay well within the GCWR of your vehicle.

[cpaharley2008]

You may also want to read the first thread under "Towing...." for some definitions and explanation of items spoken often here--
http://www.fiberglassrv.com/forums/f...rms-55514.html

[MaryNJWildlife]

I found the previous numbers on the internet, cars.com, for the model of my SUV. So now I went to the manual. It directed me to the "F.M.V.S.S./C.M.V.S.S. certification label on the driver's side lock pillar." Unfortunately that label doesn't specify gross weight or axle weight ratings. It does say max payload is 900 pounds which is a lot less than the 1195 I had.

From the manual, this is the only other info:
Max trailer weight = 3500
Max tongue weight = 350
GCWR = 8300

I guess I need to go weigh the Murano to establish its curb weight.
The Parkliner only has one axle so I don't expect it to have a separate GAWR, should I?

[MaryNJWildlife]

Originally Posted by cpaharley2008

You may also want to read the first thread under "Towing...." for some definitions and explanation of items spoken often here--
http://www.fiberglassrv.com/forums/f...rms-55514.html

Thank you, Jim. I'm saving this and will memorize with diligence

[Jon in AZ]

Originally Posted by MaryNJWildlife

...Unfortunately that label doesn't specify gross weight or axle weight ratings... It does say max payload is 900 pounds which is a lot less than the 1195 I had...The Parkliner only has one axle so I don't expect it to have a separate GAWR, should I?

You might ask your dealer about the other ratings. The one I'd be most concerned with is the the rear axle weight rating. Between tongue weight and people, pets, and cargo in the back of the vehicle, it's the most likely to be overloaded when towing.

Payload may be less because you have AWD and perhaps other options. They add weight.

The trailer does have a GVWR (total trailer weight including the tongue) and a GAWR (just the axle weight, not counting the tongue weight). The latter is based on the specs of the axle installed by Parkliner, likely a 3500# axle, or possibly limited by the tire ratings. In any case it's rarely an issue as long as you are within the GVWR of the trailer overall.

[MaryNJWildlife]

Update: I purchased the "Air Helper Springs" by AirLift for the Murano and had them installed. I really like them. Even with no trailer attached, the SUV rides better. It has less bounce in the back. When the camper is attached, there is less sag and the ride feels more stable. I don't pack the rear of the SUV with heavy stuff, only light things. I distribute the weight in the camper adequately so now it looks level. I'm very happy with the AirLift system and don't plan on installing a weight distribution kit. I've been passed on the highways by many large trucks and there is no sway whatsoever.