Roof Rail Delete
 

Just a quick question. I did a roof rail delete. I purchased some universal plugs but doesn't fit so well. It never really bothered me because the X5 was always in the garage but now I have to park it outside. I don't want water dripping inside the holes because of the plugs being not a perfect fit.

Does anybody know where I can get perfect fitted plugs for the roof rail mounting holes?

Thanks

I believe you need RTV sealant to make them water tight. I can't think of any OTS plugs that have a rubber seal on it.

When I took my rails off, I took some clear vinyl and taped over the plugs so they were water tight. I reinstalled the rails after 1 year so I don't have long term durability of the vinyl (rated 5 years outdoors).

Your X looks bald! :)
Why do guys want the roof rails off??

Agreed. I kept a ski rack on it for six months because I thought it looked funny with nothing up there. Note I do not, and probably never will, ski.

There have been reports that roof rails cause a lot of drag and hurt gas mileage. Yes, Roof Boxes And Ski Racks Really Do Cut MPG—More Than You Might Think

I remember reading stuff on Ecomodders, etc. I didn't have mine off for very long and I don't remember if I had any mileage increases with them off, though.

I get that. Removing the ski-rack had a distinct and immediate improvement in mileage (up 1.5-2MPG), comfort (noise) and drivability (at least subjectively it felt less wind prone).

The OEM factory rails, mounted front to back (longitudinally) , are unlikely to have any measureable effect on fuel consumption or drag etc.

Mount some cross rails (laterally) on them and its a different story.....

I don't know enough about flow to really know how it affects drag. I'd expect the lower amount surface area the air stops on to have a big effect, but you could be correct.

I don't really know squat about it either but it's pretty clear that the low frontal area of the OEM longitudinal rails will have little drag. The drag of the spaces underneath the rails is probably greater (pressure differences create drag - layman's description!). But even that is pretty low.

Removing the rear spoiler probably makes more difference at speed but it would make the car look neutered... :rolleyes:

Adding lateral rails can typically add 5-15% to most car's drag coefficients.

Roof Racks a Drag on Fuel Economy | Berkeley Lab

I take mine off in the summer. The X5 handles so much better without the rails and ski rack up top. That is a lot of weight up there.

I do think removing the rails does look funny on stock non-is models.