Seems like a slim subject for a post, but perhaps some of you don’t know it can be done. The shafts that stick out of the front of the van, and to which the wiper arms are attached, have a plain bearing sleeve. I bet that over time any lubrication in the sleeve is lost and the shaft gets that little bit harder to move.
I have a spare wiper assembly in the barn, so here are some pics of the shaft and housing.
Front view, showing the splined area that the arm meshes with, the threaded end for the wiper arm securing nut, the threaded base that the big nut that holds the housing in place on the sheet metal (the housing is also held to the van by phillips headed screws that you can see at the front edge of dash board near windscreen). You might be able to make out a circlip just above the large threads.
Circlip removed, 2 washers, and a rubber grease seal.
Back, inside view of above, circlip and washers removed and the shaft pushed back. This exposed shaft is what need lubed.
Make sense? Ok, out to the van. First pry off the plastic cap at the base of the wiper arm. See the little slot on wiper arm base where you can insert a screwdriver to twist off the cap?
Cap off, 10 mm nut exposed. Often it is pretty rusty in here.
Remove nut and thin washer, wiggle wiper arm and remove from stud. The splines will look cruddy like this one, no worry, clean the splines out with a pin/needle. It’s these splines which bite into the softer metal of the wiper arm that prevents the wiper arm from slipping, not how tight the 10 mm nut is. So spend some time to clean the splines out.
Pry off the black plastic shroud. Careful, don’t scratch the paint.
That big nut is supposed to be somewhat tight, 69 in. lbs (8 Nm). You can see the golden coloured circlip, remove that (don’t lose it!).
In this pic the circlip and the 2 washers have been removed, and the 10 mm nut put back on the shaft (to give me something to hold on to). The shaft was pushed in and out a little and that made the grease seal pop out.
Bentley says to use molybdenum disulphide grease on the shaft, I used gear oil. If I had the shafts right apart then grease would make sense, but seems to me that oil is better in this situation.
And then it is just a matter of putting it all back together. The circlip might be the hardest part to re-install. The wiper arm nut is tightened to 5 Nm (43 in. lbs). Do not over-tighten, risk of strippage! I place the arm on the shaft and before tightening the nut, I move the arm into proper resting position Then tighten the nut and the assembly draws up without moving out of position. Oh, and another thing, I glob some waterproof grease onto that nut to reduce rusting.