Faulty J-bolts on Yakima rack?

[spudz]

I have owned a Yakima Outdoorsman 300 full truck rack for about 3 years now. I’ve got it rigged to Toyota Tundra and I typically carry 1 polyethylene kayak (~ 65 pounds) on it over freeway and paved roads. At most I’ll carry three kayaks on it ( ~ 65 pounds each = 195 pounds).


I have not had any problems with this system until recently. This past summer I loosened a “J” bolt so I could relocate a tower. The J-bolt snapped. I replaced the snapped j-bolt with a new one that Yakima provided. As I loosened the bolt on the opposite tower, that J-bolt snapped too. Thought that was odd to have another snap. All bolts had anti-seize applied to them upon initial installation, hex nuts were moving when removed from the bolts. I noticed the original J-bolts no longer maintained their original "J" shape. The hook part of the “J” shape of the bolt pulled away and no longer had the original “J” shape (see photos). I then attempted to remove another J-bolt from a different tower to see if that was becoming disfigured too. As I loosened that bolt, it snapped too. I now have had a total of 3 of 4 J-bolts snap. All 3 had snapped close to the base of the threading. Upon inspection all original 4 J-bolts are disfigured where the hook end of the “J” bolt has been pulled/stretched.


A side by side of a new J-bolt, the solitary unsnapped bolt and 2 of the three snapped J-bolts.


A pic of the bent J-bolt sitting on top of a new J-bolt.

I’m happy that Yakima replaced all the J-bolts. But they couldn’t explain why this was happening. Would like to know if any other Yakima users had similar problems? Is this a common trend in the j-bolts used for the Outdoorsman 300?

[Dannowar]

Three kayaks that high up I would imagine puts a lot of stress on the racks.

[spudz]

Typically I’d carry 1-2 kayaks on the rack. Seldom would I carry three. When I spoke to the Yakima reps they stated that three kayaks, even 4 kayaks, wouldn’t be a problem as long as I stayed below the 300# load capacity. However, they still weren’t able to explain why the bolts would fail.

[RedSledTeam]

It appears that you are over-stressing the J Bolts. What do they clamp and how much torque does it take to get it to adequately clamp up?

[rossman]

Have had my Outdoorsman for close to 10 years now on 2 trucks with the same J bolts. No problem with mine. The bottom of the J bolt should fit into an 6 inch long by 3/4 inch square of extruded aluminum. Wanna make sure you are using those and that they lay flat under the lip of the truck bed. If they are missing or not laying flat I can see them bending and breaking.

[mrJB]

Even though Yakima is based in Washington, I wouldn't be surprised if they are now outsourcing some parts (i.e.,China). Wouldn't want a failure while underway...

Don't know if they would be stronger, but you might want to cut down some trailer "U-bolts" and give it some stress and check before mounting. Beyond that, you could go to a machine shop and have them make you a set out of grade 5 or 8 steel...

[YakDout]

See if you can find higher grade bolts through www.fastenal.com

[makobob]

I looked at Rossman's in Asuncion and wondered why not just use a backup plate and through bolt them?

[spudz]

RedSledTeam , The J-bolts secure the tower to a 6” long piece of aluminum that fits snugly under the truck bed’s rail. Not an incredible amount of torque applied.

[spudz]

Thanks Rossman, The aluminum bar is flat and snuggly secured to the truck bed rail.

[spudz]

MrJB, Not sure where the original J-bolts were made. However, new J-bolts came in a bag/kit stamped made in China.

[spudz]

MrJB & YakDout, I’ll keep the replacement J-bolts on for now and check every few months for any disfiguring. If these replacements falter, then I’ll take your advice and make a trip to a machine shop/cut down some trailer U-bolts. Would hate to lose the rack/kayak while driving down the PCH!

[spudz]

Makobob, back plate under truck bed rail and through bolt through the back plate and rail plate section of tower?

[jruiz]

Have had mine on two different trucks for two years now. Didn't notice any problems when I switched them over to a different truck last May.

[alanw]

Assuming the bolts didn't come that shape originally...

If the bolts were loose, then they bent during use. Cheap bolts.

If the bolts were still tight, they were over torqued during original installation.

My .02

[makobob]

Originally Posted by spudz

Makobob, back plate under truck bed rail and through bolt through the back plate and rail plate section of tower?

YES, it does put holes in truck but it would be bullet proof.

[pbb]

I suspect your piece of aluminum is the culprit, possibly combined with over tightening.

Think about the way they have bent. That suggests that the load is all getting applied to the end of the J and there is torque pushing down and out. Whereas without the aluminum block the load would be at the bottom of the J and not pushing out so much.

[Mahigeer]

It looks to me that it is caused by having a load (kayaks) at the end of a lever (the uprights) putting sideways pressure on the J bolt/s.

As the kayaks on the top move from center to left and right on the top (looking at the road from driver's seat), they exert load on the j bolts through the up rights. Which are now a lever. One end the j bolts, the other the kayaks.


I think the only thing to do since the level distance cannot be changed; is either to lighten the load, use a thicker diameter j bolts, or jay bolts made from a stronger material.

Some modification may have to be done to accommodate the thicker diameter j bolts.


Good luck.

[jruiz]

If you look at the area circled in the picture, there seems to be a wormhole or rip in the space-time continuum. Or your cross bar is bent.

[Mahigeer]

One more suggestion which I am not sure it is mentioned by others.

Drill a new hole in the corner plate and the truck, so instead of "j" bolt you can use a "u" bolt and fender washer.

That way the pressure is not at the short section of the "j" bolt, but up to the washer and nut.

A stainless steel "U" bolt and washer will keep from rusting and prolong the life of the fasteners.