I’ve been shunting curtainsiders for nearly 9 years now (yeah, it shows
), and although I’ve had to get the brake cleaner out on several greasy patches over the years to save both me and the next drivers getting caked in it, I’ve yet to see it up here before…
The rest of the trailer was pretty much spotless. It was one of their lower trailers, but not that low! So someone getting over-excited whilst ‘bungeeing-up’ their air lines was out of the question 
Just curious as to whether anybody has any suggestions?
…A greasy tree?
…A really messy fitter greasing-up the curtain track?
…Grease lightning?
…
To expand the subject slightly…
Why do some drivers feel the need to leave the entire contents of the fifth wheel on the side deflectors after coupling/uncoupling?
Ken.
Shame as its a clean trailer apart from that, not the most fastidious of people but that would annoy me pulling it. Perhaps a greasy truck wash brush? Defeated the object…
That high up must of been a grease monkey.
Looks like the mast of a forklift has rubbed off it when the curtains were open- mystery solved 
Transc:
Looks like the mast of a forklift has rubbed off it when the curtains were open- mystery solved 
yep most probable cause forklift mast . Once saw a 3 week old curtainsider that had the mast of a Moffet mounty rubbed on to it in about the same place -boss thought it would be a good idea to clean it with cellulose paint thinners - one lovely black mess on a white curtain - new curtain required .
Transc:
Looks like the mast of a forklift has rubbed off it when the curtains were open- mystery solved 
Ah, good thinking Batman! Yeah I reckon we have a winner, didnt think of that one! Blimey, I was lucky to find the front curtain pole in a straight line then! One of the disadvantages of not letting drivers near the trailer when being loaded I guess.
beefy4605:
Transc:
Once saw a 3 week old curtainsider that had the mast of a Moffet mounty rubbed on to it in about the same place -boss thought it would be a good idea to clean it with cellulose paint thinners - one lovely black mess on a white curtain - new curtain required .
This Stuff would’ve saved him a fortune! Not sure I’d be too keen using it on a show-winning paint job, but a little bit works great on most vehicle-related surfaces.
…bit late now though I suppose 
We have had oil marks like that on some of our trailers so I appreciate the info.
W