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2012 Premium 2.5
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I modified the roof rack of my 4th gen Outback so I could carry building materials. You can’t carry a sheet of plywood on the stock rack. This mod doesn’t require any cutting or drilling of the original car parts and is entirely reversible. It does require a lot of cutting and drilling of steel, and some welding, but you might be able to adapt it to your own skills.
I removed the original cross bars and fastened a long straight metal rail above the molded plastic roof mount on each side of the car. Now, new cross bars can be fastened anywhere along the length of the new metal rails.



For the metal rails, I bought a 10-foot length of strut channel at Home Depot/Lowes. Strut channel is a C-shaped square bar, about 1-5/8 inches square, with an open slot down the length of one side. It is sold in the electrical department and is used to mount conduit, pipes and fixture in commercial construction. Actually, I used the smaller half channel, which is 1-5/8 x 13/16, but the full size channel is much stronger, if you don’t mind the taller profile. Cut the 10-foot channel in half to make two 5-foot rails.

The new rails are attached the car’s existing black plastic roof mount on small pedestals I made from pieces of steel angle stock, also from Home Depot/Lowes. For the cross bars, I adapted my old Thule roof racks from my last car. Instead, you could buy some square steel tubing or use more strut channel.

01 – Pedestal Parts
Parts A, B, C, & D are the 4 pedestal bases that bolt to the car where the original cross bars had been fastened. They are made of 2”x2”x1/8” steel angle. The two with large [5/8”] holes are 3” long and go at the left front (A) and right rear (B) positions, where the original cross bars were fastened with pivot bolts. The two with pairs of small holes (C & D) are 4” long and go where the original cross bars had latched into large oblong holes. Note that the holes are offset by 5/8” on the otherwise identical pieces. This is because the holes in the car roof are 1-1/4” farther apart in the front than in the back.
The two rings shown at upper left in the picture act like tall washers when using the original pivot bolt to fasten the pedestal bases. They are made of ½” steel plumbing pipe. Without them the bolts are too long and bottom out.
The two pieces shown below the rings fit down inside the oblong holes in the car and act like toggle fasteners to grip the edges of the oblong holes when the bolts in the other two pedestal bases are tightened. These parts are made from a piece of 1” square tubing cut in half lengthwise with nuts welded behind each hole for bolts to fasten. ¼” x 1” steel bar stock, drilled and tapped would also work.
The parts at the right in the photo are the pedestal tops, made of 1-1/4”x 1/8” angle. Part ‘a’ goes with part ‘A’, part ‘B’ with part ’b’, etc. One side of each piece has been drilled 2” OC for 3/8” machine screw and nuts are welded behind each hole. These will be the top surfaces of the pedestals. The adjacent sides are drilled with clearance holes for ¼” machine screws that will fasten the piece to the corresponding base, which has been drilled and tapped. See other photos for more detail.
The parts in the lower right of the photo are simply pieces of 1” x 1/8” strap steel drilled 2” OC to act as washers for the 3/8” screws that will join the rails to the pedestals.



02 – Pedestal Parts in Progress
In the upper left of the photo below is the pedestal base for the left front corner of the car, viewed from the side (A). The pivot bolt from the original cross bar is in place, through the ring of ½ inch pipe that takes up the bolts excess length. The length of this ring is critical so that the bolt hits bottom just as the pedestal base is held tight against the car. This is a shoulder bolt, designed to stop at the end of the threads rather than at the bottom of the head. If the ring is too short the pedestal will never be held tight. If it’s too tall the shoulder won’t hit bottom and the bolt could work loose over time.
The large hole in ‘A’ & ‘B’ fits over a raised boss in the car’s black plastic roof mount, where the pivot bolt goes through.
Ignore the radius you see on the upper left corner of the pedestal (A). All the vertical sides of the pedestals will be cut short in the next step.
In the lower left is the pedestal base for the right front corner of the car (C). It is shown with the toggle assembled with two bolts as it would be when installed on the car. Again, the vertical side will be cut down and then drilled later.
On the right of the photo are the pedestals for the rear of the car. Their mounting holes are drilled 5/8” closer to the vertical side, so the verticals will be in line with those at the front of the car, which is wider than the rear.




Installing the Pedestals with Toggle Fasteners
There is a special technique for installing the toggle fasteners in the oblong holes where the OEM cross bars originally clipped into the plastic roof mounts. See the sequence below.




03 – Marking the Pedestal Height
Once the pedestal base fits in its designated place on the car’s black plastic roof mount, its vertical side must be marked and cut the correct height and angle. The pedestal top, which bolts to the vertical side of the base and projects horizontally back over the base, must be high enough to clear the raised part of the car’s black plastic roof mount, seen in the left of the photo. It must also be on the same plane as all the other pedestal tops.
Here is how to mark the cut lines. Temporarily fasten each base in place on the car. Clamp a piece of metal angle or a narrow piece of wood to the vertical side of each base. On each side of the car, lay a straight edge on top of the piece clamped to the front and the rear pedestals. Loosen each clamp enough to raise, lower and rotate the piece until it is in line with the straight edge and until the straight edge clears the black plastic roof mount and is parallel to the straight edge on the opposite side of the car. Remove the straight edge and mark the top of the clamped piece.
Now the bases can be cut along the marked lines and the pedestal tops can be fitted to the bases. The vertical sides of the tops will also have to be cut to align with the bottom surface of the base, but that can be done in the shop and not on the car.





04 – Assembling the Pedestals
After cutting the vertical sides of the pedestal base and top to the right height and angle, they can be fastened together. Welding would make it impossible to insert the lower fasteners under the overhanging top, so use removable fasteners. I used 1/4-20 screws and tapped the holes in the bases, so nuts are not needed. The holes in the tops might need to be enlarged for enough wiggle room for alignment during final assembly.
In the following two photos the pedestal parts have been painted, positioned and are being aligned with each other using a straight edge before tightening the fasteners. Also during alignment, check the distance between the left and right pedestals at the front and rear of the car, so the two rails will be parallel. But don’t worry too much. The pre-punched holes in the strut channel rails allow quite a bit of free play.





05 – Fasten Rail to Pedestal
Here the rail has been placed on the front and rear pedestals with the pre-punched holes aligned with the holes in the pedestals. Since the pre-punched holes are large and elongated it should not be hard to find a spot where all four holes align. The 2-hole washers we made from 1” strap in the first step keep the 3/8” bolts from going through the oversized holes in the rails.




06 – Cross Bar Mounts
These mounts fasten my old Thule brand rectangular cross bars to the new rails. Part ‘A’ is a short piece of 1-1/2”x1/2” steel channel drilled with clearance holes for two 3/8” bolts. The hole spacing depends on the holes drilled in parts ‘C’, which are 8 short pieces of 1-1/4” steel angle. Four are drilled with clearance holes for 3/8” bolts and the other 4 are drilled for 3/8” thread tap. Part ‘B’ is cut from a piece of 1-1/2” square steel tubing and forms a stirrup that will fit over the Thule cross bar and hold it in place.
Example ‘D’ shows the relative positions of each of these parts. A 3/8” bolt will come up through part ‘A’ into the tapped hole in part ‘C’ under the stirrup (B). A 3/8” bolt will go down through part ‘C’ nearest the center of part ‘A’ and hold the cross bar to the rail. Both parts ‘C’ will be welded to part ‘B’ to form a single piece. Cut a scrap of wood exactly the height of the cross bar and put it under the stirrup (B) while welding to get the correct spacing for the bar.



Here is the finished cross bar mount (rusty from 2 years’ use), showing the bolt head holding the bracket to the bar and the bolt & special nut that hold the cross bar to the rail. The special nuts come tapped for different size bolts. I chose 3/8”.




07 – Rail and Cross Bar
This is a close-up of the front right corner of the roof rack showing a load lashed to the cross bar. At the extreme right is the front-most support I added below the rail. It is a piece of angle welded to a piece of T-shaped steel. It is bolted to the bottom of the rail and simply rests on top of the car’s black plastic roof mount. At the rear end of the rail (not shown) there is a gap of about an inch between the rail and the plastic roof mount so I filled in the gap with a small rectangle of rigid PVC plastic, fastened only to the rail and resting on the roof mount. These two end supports are probably more psychologically useful than physically, but they can’t hurt.
Remember, the load is really held to the car by the original four mounting points, so don’t overload the new rack even though it holds more than the old one. I’ve used this rack for a couple of years now without problem. I keep a cheap ratchet wrench with a 9/16 deep socket in the back of the car to position the cross bars whenever I need them.




 

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Snail - I know I'm years down the track from your original post, but thanks so much for the time & effort you put into this.

I work in a fairly niche field and have to carry loads on the roof - not always heavy, but bulky and long that would be most suited for a tray...I've had my heart set on an Outback but the built-in crossbars have been a real concern that has held me back from buying. I had come up with the idea of using steel strut in place of the built-in bars, but without seeing how they could be modified I was worried it could turn into a very expensive exercise.

So - thanks for the helpful post!
 

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Nice! For the record, the C-shaped channel he speaks of goes by the trade name Unistrut, though they are not the only manufacturers. It comes in lots of different finishes too, especially flavors suited for outdoors on a salty car roof.
Unistrut is cool because there are a multitude of fasteners (like the rectangular nuts pictured) that work with the system to attach it to things, and to attach things to it.
 

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2014 Outback 2.5 Limited
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I've been trying to figure this out for a few years. You sir, are a genius!
I'm going to try fabricating something similar from wood
 
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