This one is driving me a bit nuts. This staining keeps coming back - I can remove it but it takes a bit of work. It's not greasy, seems to drip both straight down and driven back by the wind while in motion. I get some of the same staining on the front driver rim as well.
I haven't put together whether it comes with rain. Our front AC drain is stopped and water will pool on the roof in the front driver corner and come down right about here, so it's probably related to that - however, fixing that issue likely only slows this down and doesn't eliminate it? It's interesting that it only seems to start at the door hinge and go down from there - so if it's from the roof, why wouldn't I see starting from up high?
Has anyone else seen something similar?
It looks like it is rusting the hinge rod creating the stain.
Looks like rust.
Pull out a magnet and check both screws and hinge. May even be able to eyeball the source.
Hopefully the screws-- easy to replace with stainless steel.
When I talked to Xtreme about a rust stain like that, only much smaller, they said ti was not the hinge. The hinge is SS.
On mine, I had a small delamitation along the edge of the slideout opening. When I fixed it, the rust disappeared.
I think you have a leak behind the vertical trim strip that is letting water get to the interior steel framing. You will need to pull the strip off, fix the seal in the joint and reinstall the trim strip. You may find that the sidewall is delaminating behind the trim strip. It could be as high as the top of the strip near the roof and running all the way down behind the strip before showing itself.
Let us know what you eventually find,
Rich
Any idea how is the the strip attached?
Is the center piece flexible? Could be where you remove the center piece and screws are holding the channel. I would wait until someone that knows forsure chimes in.
Look inside compartment. Could it be steering gear leak or from something inside compartment. . . Also thought about front wheel bearing leak. . .
Not coming from inside the compartment - I think Rich has the right idea with it behind a leak under the strip.
I had similar on one of my hatches a few years back. The area above the door seal is Carbon steel that goes up then makes a 90° bend. All of my hatches those areas were starting to rust do to OE inferior paint work. I took the time to wire brush all of them one weekend, then painted with a rust encapsulating paint (Eastwood) POR15 is another that would do nicely.
Could also be a leak around one of the clearance lights and the water tracking towards that strip area and down.. I'm not familiar with how the ones on a newer coach were done, but if they have gaskets or screws that are sealed with caulk, you might investigate that area as well.
First thing to do is put a level on trim strip and see if the coach is lower at front as any moisture in trim will be heading that way.
Take trim strip AND the vertical one off and see if there is any indication of water entry. Clean it up, replace strip then use a clear caulk to put a very small bead on both sides of vertical one and only on upper edge of horizontal trim.
This should fix it or give you some insight into another issue when trims are off. When replacing screws put a dab of caulk in hole to seal underside of screw head.
Johnh
Another thought is to look closely at the joint/moulding where the front cap, roof, and sidewall meet. Looking at photos of a 2007 Nimbus, it looks like there's a seam/moulding that runs across the roof where the front cap joins the sidewalls, as well as an upper moulding that joins the roof to the sidewalls.