Hitch for extra Cargo

[TaMbALoLoNg]

Just wondering if anybody had any problems hauling your extra cargo through your hitch vs the roof rack? I got 3rd row so when the seats are up theres not much left for luggage space. The good thing is you dont need to climb to offload, its right there.

[GoVols!]

That right there is why I got the hitch. Uhaul sells one of those with foldable sides about 3ft high and a locking top. Ive seen it used for firewood, luggage, etc. The rear box also does not impact gas mileage like the roof boxes do.

[TaMbALoLoNg]

Originally Posted by GoVols!

That right there is why I got the hitch. Uhaul sells one of those with foldable sides about 3ft high and a locking top. Ive seen it used for firewood, luggage, etc. The rear box also does not impact gas mileage like the roof boxes do.

Makes sense, never thought of that. That's another good reason.

[JCL]

Problems with this type of carrier generally relate to overloading, and load placement. The OEM (or any other) hitch is designed for a point load, applied vertically, approximately 8" from the receiver pin. I have the E53 documents, and the E70 may be slightly different, but the theory is the same. If you have the E70 guidelines, just adjust the calculations.

Using the E53 guidelines, you can't apply the rated tongue weight of 600 lbs to your carrier, unless you can get the CoG within 8" of the receiver pin. If you are 16" out, then you have 300 lbs capacity, at 24" you have 200 lbs capacity, and so on. This is ignoring dynamic effects, and you can see these carriers bounce significantly over bumps.

All the early problems with E53 hitches that I saw, related to bending moments from using cargo carriers. The carriers essentially bent the rear pans of the vehicles, due to the load profile.

When the carrier manufacturers talk about using a certain class of hitch, you need to take into account that your hitch is bolted to a unibody, not a frame, so the bending moments are the limiting factor.

Now, load it up with tents and sleeping bags and so on, and none of this will matter. Put some weight in it, however, and make sure that you stay within the design limits of the hitch mounting.

[GoVols!]

This is the box I was talking about.
U-Haul moving supplies: Carpod Carrier

[JCL]

Originally Posted by GoVols!

This is the box I was talking about.
U-Haul moving supplies: Carpod Carrier

The centre of gravity (if the load is distributed equally front/rear) appears to be about 24" from the receiver pin, according to the drawing in your link. The stated capacity of 450 lbs may be OK if you had a frame-mounted hitch, but the BMW hitch won't hold that safely; it is rated for 600 lbs at 8". At 24" to the load centre, the capacity comes down to 200 lbs, if you have the OEM hitch. Deduct 50 lbs for the carrier, and you have a design capacity of 150 lbs of cargo. If you are under that load, you should be fine.

[TaMbALoLoNg]

$270 GoVols wow. I got mine for $40 but the original price was $110. 500lbs max load, I wont be close to that.

[JCL]

Originally Posted by TaMbALoLoNg

500lbs max load, I wont be close to that.

More like 150 lbs maximum capacity. Guess you didn't read the posts above?

[GoVols!]

Where did you find the rack for $40? I havent bought anything yet. Waiting until I need it after the kids come. For $200 bucks saved I can use tie down straps rather than having the sides...... Pretty much plan on using it for a cooler and a couple suitcases. Don't really need 500lbs of crap back there.

[TaMbALoLoNg]

Originally Posted by GoVols!

Where did you find the rack for $40? I havent bought anything yet. Waiting until I need it after the kids come. For $200 bucks saved I can use tie down straps rather than having the sides...... Pretty much plan on using it for a cooler and a couple suitcases. Don't really need 500lbs of crap back there.

Google Haul Master and you'll find it.