I also use the 4 bike pro-rack. Excellent product and have no complaints at all.
As wright stated, our particular model requires a slight modification. The base poles are too short. One needs to fabricate a longer pole.
On my previous HW256, it worked fine out of the box. That is because the sprockets would land over the front storage bin which was lower than the roof. The HW296 has no front bin so the bikes basically have to be transported level. To achieve level, you need to raise the front fork attachment bar higher than it is designed to go. To fix this problem, you simply need to get longer base poles.
Wright. Do you have any pics of your mod for this gentleman?
2006 HW256 (previous pup)
2013 Chevy Tahoe
Equalizer WDH 1000#