PRINZU INSTALL -- WITH A TWIST

I bought the Original (updated) Prinzu roof rack (not the Prinzu Pro) for my 3rd Gen Tacoma Double Cab, and I am looking to install it. The question I have, which maybe some of you here with practical or technical expertise can answer, is whether I should use the Pro mounting system or the Original.

I was watching the manufacturer's install videos for both, and the mounting method for the Pro looks better to me.

The Original method: Load the surface around the installation holes with silicone sealant, then press the spacers into the silicone.

The Pro method: Put rubber washers around the holes (per the video, with a thin layer of silicone sealant on the underside of the washers), set the spacers on the washers, then partially fill the holes from the top of the spacers with silicone sealant.*

My thinking is the rubber washers clamped under the spacers with the force of the tightened bolts, with silicone sealant down the hole, will make a better seal against water intrusion than a bead of sealant under the spacers. I also think the washers will provide more stability and shock absorption than a squished bead of silicone. So I'm wondering if I can use the Pro method on my Original, assuming I can source the correct washers.

I contacted Prinzu / CBI about my idea. They won't say whether it will work, which I understand. However, the only concern their rep mentioned was that due to the height of the washers, the bolts sold with the Original might not go as deep into the mounting holes in the cab. I don't think that's a concern, as the bolt threads seem long enough to hold either way; the washers are fairly thin; and the washers are replacing what would be a bead of silicone sealant. (I'm reluctant to source longer bolts and risk not getting the right hardness, tensile strength, thread pitch, etc.)

Prinzu / CBI won't sell me the washers, but they did give me the specs:
3/8" x 13/16" x 3/32" EPDM Washers

So, what does the hive mind say? Get the washers and use the Pro method, or use the Original method?



* If anyone wants to compare the actual instructions --

Original:
https://youtu.be/OJRHSbytBDg?si=Y3k1YGxDQygebeKm

"Next apply silicone over the holes
Then place the spacers over the holes and silicone and press down making sure a good amount extends around the edge."

Pro:
https://youtu.be/UxB3KBfvLdM?si=9Vc_UI9iz2gry88x

"4. Setting the rack on the vehicle.
● Make sure the Vehicle is clean around the factory mounting
points so the rubber washers will seal properly to the roof.
Place the rubber washers over the mounting points, place
the aluminum spacers on top of the rubber washers, now fill
the inside of the spacers with the silicone. You won’t need to
fill the entire spacer with silicone, just make sure there is a
good amount inside the spacers."

 

i think this is splitting hairs. by the time the rack is tight enough to not move, the rubber will not be offering any real vibration resistance because the other half of the bolt is bypassing it.

and i've also seen rubber washers like that curl up and self-eject right near tightening torque.

my preference would be to skip the rubber washers and use only silicone. adding washers to the silicone adds an additional failure mode.

 

Tbh I just completely filled those holes up with silicone, my thoughts are always that more protection is better than less