Originally Posted by MikeW
Hi! We've got a 2004 Grand Cherokee V8 (5.2L) and looking at purchasing a 25' Safari. Any one have any thoughts about the Cherokee as a tow vehicle? According to the specs, the Jeep should not have a problem pulling the trailer.
These are specs I found on the 'net for the Grand Cherokee:
Curb Weight: 3995 lbs.
Gross Weight: 5200 lbs.
Base Number of Cylinders: 8 Base Engine Size: 4.7 liters
Base Engine Type: V8 Horsepower: 265 hp
Max Horsepower: 5200 rpm Torque: 325 ft-lbs.
Max Torque: 3600 rpm Maximum Payload: 1100 lbs.
Maximum Towing Capacity: 6500 lbs.
And these are from the Airstream website:
Safari Trailer MODEL - 25' W
FACTORY WEIGHT, W/O OPTIONS OR VARIABLE WGT. - 4920 lbs
HITCH WEIGHT, W/O OPTIONS OR VARIABLE WT. - 680 lbs
ADDITIONAL ALLOWABLE WEIGHT,INCLUDING:NCC - 942 lbs
OK, lets start with the Max allowable payload of the Jeep.
Specs say 1100 lbs, but subtract the max allowable from the curb weight you get about 1200 lbs. That’s 1200 lbs total, no people, no dogs, no beer, no gear.
From the 1200 lbs, subtract the weight of two people. The FAA allows 170 lbs per person, so we'll assume that - so we subtract 340 lbs for people (more or less -- WAY more in our case).
Now, we have 1200 lbs - 340 lbs = 860 lbs total load available.
From the Airstream specs, they call for an unloaded hitch weight of 680 lbs.
So, 860 lbs left after two people, less 680 lbs of hitch weight = 180 lbs for everything else.
I assume you will want a weight equalizing hitch - weight EQUALIZING hitch.
An equalizing hitch does not make weight magically disappear. It transfers some weight from the rear tow vehicle wheels to the front wheels, and a bit to the trailer wheels. But it does it at a price. There are considerable forces - both static and dynamic - that are induced on both the tow vehicle frame and the trailer frame. Think about how the weight is transferred with an equalizing hitch - it is all transferred through the frame - and in opposite directions that a tow hitch (dead weight) is designed for.
I would guess that a good weight equalizing hitch with a decent safety chain (6,000 lbs test MINIMUM), would be in the neighborhood of 100 lbs.
So, from above - with NOTHING ELSE in the Jeep (or the trailer), we had 180 lbs of load left. Subtract the weight of a good equalizing hitch, and you have only 80 lbs left for camping gear, adult beverages (got to have those), dogs, tools, friends, and kids. With none of the above in the GC, you are already dangerously close to the territory of negative numbers.
Using real numbers in a real world situation, a 6500 lb trailer would require a MINIMUM of 10% of the total weight on the tongue - 650 lbs.
Do the math on the payload of the Jeep, and you will see that a 6500 lb trailer is really not a realistic tow for the vehicle. Some Forum members suggest downgrading ANY tow vehicle by 20% to 30% (70% to 80% of max rated capacity) to estabilish a "margin of safety" or, said otherwise, a "comfort zone" for peace of mind.
Mike, don't want to rain on your parade, but you have asked a question that brings a lot of passion to the surface here on the Forums. There are others that are active that would just as vigorously defend towing a 25' Safari with your Grand Cherokee.
Remember, the "add ons" for towing (Power Steering Cooler, extra Tranny Cooler, etc.) are designed to minimize problems, not increase total carrying or towing capacity. The actual "towability" limiting factor of any vehicle usually remains unknown to us (non-Auto Industry) laymen. It might be the engine, the transmission, the rear end, brakes, wheel base, steering design, tires, cooling, or any other individual part of the vehicle. A Tow Rating is more about controlling a trailer rather than straight line acceleration. Think of it this way, in an emergency situation, which would you rather have under you, a 500 HP drag racer or a 500 HP Over the Road Truck? Extreme examples, but when your belt deep in stopping, avoiding, and controlling, I would suspect that just about the only thing goes through your mind is "I wish I had more”......brakes, stability, direction control, wheel base, mass -- take your pick.
On the engine specs for the Jeep; Max HP at 5200 RPM and max torque at 3600 rpm. Man, that engine will be screamin' at those speeds, and require a generous dose of 2nd gear to maintain the HP and torque rating at speed.
OK, I'm off my soapbox for now, the final decision to tow or not to tow rests entirely on the driver. You are "pilot in command" of your vehicle. Just remember that the design engineers put tow limits on vehicles for valid reasons, the numbers are not "best guesses" or assigned capriciously.
Also, remember this, the sales people, (both Trailer and Tow Vehicle), will tell you anything you want to hear to make a sale, but probably will not stand behind you in court or at a service bay after a failure has been determined to be caused, wholly or in part, by an inappropriate tow vehicle.
Welcome to the Forums, practically any question asked will probably be answered; sometimes it's just not the answer you want to hear.
Good luck on your decision, lots of great help here, good people with a load of experience -- and sometimes differing opinions.