What Wooden Location Should I Mount My Thule Roof Mounted Top Rack System # THTB60?

Question:

Im mounting these rails onto the wooden roof sheathing of my Adventurer 89RB Truck Camper. What fastener system is recommended for blind mounting onto a wood based structure 1/2inch sheathing or perhaps the structural rafters? Obviously, the t-bolts that mount accessories must clear the railsfoot mounting screw heads. Also, the roof is 96inch wide, what is the widest center-to-center spacing that the rails can be mounted to fit available Thule crossbars/pedestals?

asked by: Jim

Expert Reply:

I have an answer for you. As far as mounting the Thule Roof Mounted Top Rack System # THTB60 to the wooden sheathing on your Adventurer 89RB camper, Thule does not recommend using the track system on any material other than fiberglass. The reason for this is because the anchoring capability of wood is not as stable as mounting the tracks to fiberglass. This could result in cargo detaching from the roof. Also, mounting the tracks to wood will void all associated warrantees. However, if there is any other fiberglass surface on your Adventurer 89RB camper, that will be a great option for an installation location. The general rule of thumb is to mount the tracks on the thickest surface you have that will still allow you to attach the nut to the M5 x 40mm screw. It is also important to make sure that you are not drilling through any electrical wiring.

As far as the longest crossbar system we have available on your 96-inch wide roof, I recommend the following parts:

- Thule ProBar Evo Crossbars - Aluminum - 79" # TH713700
- Rapid Podium Feet for Thule Crossbars - Fixed Point # TH460R
- Fit Kit for Thule Podium-Style Roof Rack Feet - 3101 # THKIT3101

With this crossbar system, you will be able to transport cargo/accessories on your Adventurer 89RB camper.

expert reply by: Bob C