I had a play with it yesterday. Seems that at a certain point the window isn't sitting quite write in the rubber on the way up and when it has to realign itself to slot back in it slows. It's fine on the way down.
Looking at it With the door card off its as if where the rubber fits to the metal part on the right at the bottom needs "tweaking" to the left a bit so that the window doesn't come out on the left hand side. I did a little video but it was crap.
In a way Nick, I have a similar problem, although for different reasons.
Long time ago, I did a stupid thing, which resulted in the truck rolling backwards with me outside of it, with the drivers' door open, and a tree in the way, which forced the door against the door restrainer, snapping that, and bending backwards on its hinges, denting the door skin against the rear edge of the front wing, as you may imagine.
My eyes water just reminding myself of that incident.
Consequently, I had to get the door skin repaired and buy and fit a new door restrainer. Having done that, I found that the restraining device fouled the front vertical window channel, not by much, maybe just by 5 or 6 mm, or so, as it traced its arc movement inside the door.
In my wisdom, I eased the window track away from the arc path of the door restraint, with a suitably stout piece of steel reinforcing bar, as you do, to give some clearance. Sadly, just as I was getting there and avoiding the "click" of contact between the two components, the vertical window track popped its spot-welds holding it to the inner door skin.
Bugger.
So I botched it somewhat, because it's a devil of a job reaching in to get at where the welds are, with some bits of brackets and screws to stop the bottom end of the window track from flapping about in thin air.
So my main problem is a proper fix for the bottom end of the window track, but that doesn't assist at all in the sluggish operation of the window mech, and fitting a new window mech isn't going to improve that aspect either.
My dilemma, accepted. However, it's what I'm faced with at the same time as replacing the mech.
Ask me why I haven't attempted it yet....
Edit - And before anybody asks, no I don't have a video of my truck crunching against the tree, thank goodness
