You might be lucky enough not to have tread rubbers along your 'running boards'. You might have extra tread rubbers, so you might have up to three per side. You might think that they are passive and maintenance free
I've recently received an e-mail from an owner of a 2004 car, which was showing lumps under the tread rubbers which needed further investigation. The rubbers can be pulled out with a bit of effort. Don't use a tool unless you're desperate, because you may damage the aluminium strip.
This photo shows how the build up of corrosion under the rubber starts to create a bump over each fastener:
Once removed, here is what was revealed:
With a bit of fiddle, it's possible to get at all the nuts under the running boards, even though the silencers are in the way. Last autumn, I spent a day taking all the nuts off, and applying Coppaslip to the threads, finishing off with Tectyl506, but I didn't lift my tread rubbers.
If you do, you may find this:
But with a bit of elbow grease, it will come up like this:
I don't have a photo of the completed job, because Jon is having to source some new stainless bolts. The trims are square punched so the bolts are round headed coach bolts, probably with a square section under the heads.
Anyway, you know what I'm like, so this morning I thought I'd check the Roadster. The rubbers pulled out easily, leaving this sight:
Slight rust on some heads but nothing as bad as Jon's. So first I wet 'n dried the rusty heads before etch priming with a small brush. Then I squirted some ACF50 over the heads.
Then I cleaned up the rubbers using Armor All, before refitting. This requires maximum concentration, some lubrication (Armor All or similar) and a blunt screwdriver. Insert the inner lip first, work from both ends into the centre, and keep the screwdriver straight.
Maximum concentration will prevent a slip, and damage!