This guide will show you how to install and modify universal gutter mount ladder racks to clear the high roof. This is a cheap, versatile and strong solution to the common problem of high roof clearance. The Highland Brand ladder racks cost about $80 per set and have a static load capacity of 400 pounds. The cross-tubes will be mounted higher than intended, resulting in decreased stability. This install will incorporate some structural modifications to ensure stability. These are a must for carrying significant weight on the modified racks.
Tools & Parts:
- Highland Roof Racks https://www.amazon.com/gp/product/B0002MABL4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
- Extra Cross Tube Bolts & Nuts
- 3/4″ EMT- Electrical conduit available at any hardware store
- 3/4″ EMT clamps
- Bolts and Nuts for EMT Clamps
- 1/4″ X 3/4″ Aluminum Bar stock’
- Drill & Drill Bits
1. The first step is to re-drill the cross-tube mounting locations on the legs to clear the high roof. There are two ways to do this. The first is to reuse the existing upper holes on the legs, and drill a new set of upper holes. This is the easiest method, but will reduce clearance for roof box clamps (and whatever else you want to mount) and reduce effectiveness of cross bracing.
The Second is to is to re-drill all four holes and mount the cross-tube as high as possible on the leg. This is the method I used and will be outlined below. The method for re-using the original upper holes is essentially the same.
Align and drill the new holes for the cross-tube mounting bolts. Do this on each leg. The original holes were used to mount the EMT and EMT clamps, detailed later on.
2. Mount the racks to the van to establish the width. Mark this on the inner tube, remove the rack and drill TWO holes of equal spacing. The extra hole and bolt will greatly improve strength and stop the cross-tubes from rattling.
3. It just so happens that 3/4″ EMT clamps fit the original cross-tube holes. I drilled out the EMT clamp holes to match and ran a 10ft length of EMT down each side. This helped prevent the rack from shaking during low RPM vibrations and cold start. The EMT runners provide great mounting locations for all kinds of stuff and make great hand holds for access.
4. I found that having roof boxes and load up on the modified racks created a parallelogram effect, which did not tolerate lateral force well (from turning, wind and cold start). This was especially apparent when driving off road with load in the boxes, I could see them swaying. I reused the original lower cross-tube holes to mount diagonal cross braces.
I made diagonal cross-braces using aluminum bar stock, bent it up and mounted it as shown below. I only made bracing for my first two racks, since that is where I mount my roof boxes.
5. I found a company called Makerpipe that makes structural kit fittings for 3/4″ EMT. You can make all sorts of things and I used it to mount my ladder (also made of 3/4″ EMT).
