Public Advisory: Baja Racks, 5th generation 4Runner.

[CuStOm]

:victory:

 

[DaveInDenver]

I disagree. The spacers under the feet, if properly manufactured with proper quality control, should prohibit the sheet metal from being touched/impacted.

From Baja's website "Load Capacity: Dynamic (while driving) 300Lb (136 kg); Static 600Lb (272 kg)". Load capacities of the rack do not include the 80lbs of the rack itself. The dynamic state of the setup is approximately 160lbs at best with the bedding and whatnot inside the closed tent. When were parked and occupying the tent the load on the rack is at most 460lbs with people and personal affects.

http://bajarack.com/?id=racks_list&model=18

It appears Toyota rated the factory roof rack at 120 lbs (page 172 in the 2015 model owner's manual). That rating may be driven solely to prevent high center of mass and not capacity of the mounts, I dunno. How the aftermarket capacity was determined would be my question, was it analytically or tested?

 

[java]

Damn that sucks!

I made the feet on my rack sit completely down in the channel, It was pretty obvious after removing the factory rack that that is where the load was carried.

 

[CuStOm]

It appears Toyota rated the factory roof rack at 120 lbs (page 172 in the 2015 model owner's manual). That rating may be driven solely to prevent high center of mass and not capacity of the mounts, I dunno. How the aftermarket capacity was determined would be my question, was it analytically or tested?

The engineer in me things that has more to do with the cheap pot metal and plastic riveted roof rack than the roof structure itself.

 

[Dalko43]

To me this illustrates the problem of roof racks. Racks get heavier and capable of more stuff but the roofs they are bolted onto do not.
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Seems to me the issue is not with Baja Racks, as I would imagine that any kind of rack that is attached in this manner and carrying this kind of weight would likely do the same thing.
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Quite simply, the problem is you are putting more weight on the roof than the roof is designed to carry.

But what is the rating of the 4runner roof? Can it really handle 300-600# only a few inches of support? I think that's a good question.

I agree. Seems the Baja only addressed the strength of their rack; which is pretty easy to ascertain. Hell, I could build a rack out of schedule 80 pipe that would have a capacity of 1,000 lbs.!

Yet, unless Baja has done some form of finite analysis on the roof of the 4Runner and their components, I'd say that their numbers are pure conjecture.

It looks like the aftermarket company has stepped up to the plate to deal with these issues, which is always a good thing, but I'm inclined to agree with the above posts. I truly wonder how much analysis has been done on the amount of weight that the 4runner roof (not the roof rack itself) can handle. Car companies have been very adamant about cutting weight where they can in the name of efficiency. If you just compare the 5th gen 4runner to the previous generation, you'd easily notice that the gauge of metal on the doors and panels is much thinner on the newer vehicle (the sound of the door closing is a dead give-away).

Between the issue of roof strength and the issue of center of gravity, I've made a conscious effort to put a minimal amount of weight on my 4runner's roof (usually nothing more than a canoe). If people are doing some serious traveling with all the back seats full, then maybe I could see the need for a roof rack on something like a 4runner (so long as it loaded properly and safely). But a lot of the overland rigs I see are driving around with empty roof racks and a whole bunch of weight (tires, armored bumper, fuel cans) cantilevering off the rear end....just doesn't seem efficient or necessary....but to each their own I guess.

 

[DaveInDenver]

The engineer in me things that has more to do with the cheap pot metal and plastic riveted roof rack than the roof structure itself.

If the roof rack is designed for a given amount of weight then there's no reason to build the underlying structure any stronger than necessary, either. It's likely the rack itself is weaker than the mount points, Toyota isn't stupid and knows a customer would rather see a bent extrusion or broken cast rack piece than a dented roof in the event of an overload. But unless someone has engineering data or done an analysis or testing then it's just a w.a.g.

 

[Badmeat]

What's referred to as the "roof luggage carrier" is actually the factory crossbars, which are rated at 120lbs. See page 171 in the manual.

The factory "rack" is capable of much higher load.

Also, understanding how everything attaches to the roof is key. There's 8 bolts that assist in supporting the load (see OP). If everything is designed and mounted correctly, the surrounding sheet metal is left unaffected, because the sheet metal is not designed to support any weight and shot not be touched by the "feet" of the rack.