Truck Rack Mount Question

this is totally fine and there is nothing wrong with mounting yakima locking blockheads or thule locking lowrider racks with this applications. we just talked about it here, and don't see a reason to seal the outside of the block with silicone, or use rubber washers. i don't see it being a bad idea either....not doing that wouldn't be a dealbreaker for me.

maybe someone else has some insight why they would suggest that that i'm overlooking??

if you were going to nut it on the under side, you could use a little primer on the drill hole.

just make sure that where you mount them, your handlebars and pedals wont' interfere with the cab or wheelwells and you mount far enough forward to accomodate your wheelbase.

Thanks for the reply -- glad you think it is okay. My main concern was inviting rust. The places where I saw that suggested it was as an effort to keep water out.

rust would be my only concern. if you self tap, you might find over time that it will rust. if you can nut it on the underside, you'd have a chance to prime the drill hole before install. this is a good reason for mounting it to a board or using something like the thule locking bedrider.
you mentioned you didn't want to go this route in your original post....but this rack, albeit a little bit more expensive, is fully locking, and if you mount it about 5" from the front of your bed, is a good place to store the front wheels of the bike. it's not permanent, and can be mounted high or low in most beds.

I would use these http://www.mcmaster.com/#rivet-nuts/=b2qgky so that there is a locking nut in the back of it. pretty sturdy I used it for my amp and other things. when out side i usually use silicone around the flat part then mount it down and wipe the excess (kind of doing like plumbers putty or doing a kitchen sink

rivnuts would be a great way to install this stuff.

I forgot to mention just for good measure put a coat of rustoleum on the edge of the metal to prevent the rusting. the silicone should give a good seal but just for good measures..

also don't use self-tapping as it does have a tendancy to rust and rust whatever it comes in contact with. also the movement from the bike without tying it down would probably bend the metal

Thank you both -- I really appreciate the advice.

I bolted mine to the bed at the top of the back ofthe bed to make it easy to get the bike from the side of the truck. I used grade 5 bolts with nylon lock nuts and washers and sprayed some rustoleum on the drilled area. Worked like a charm, but in my new truck I use a block of wood since this is a brand new truck

I for some reason have the hardest time to drill in the bed. even though i drilled in the cab for the amp and other things and lets not start in the engine. but I love those riv nuts