Greasing slack adjusters.
When servicing the brakes yesterday and following the Meritor instructions on greasing I had the thought that whoever wrote the instructions had never actually done it. How do you grease the fittings while holding your finger over the relief valve? My grease gun takes two hands where does the extra finger come from? I took the fitting out and plugged it to grease as needed. You have to remove the relief valve at the end to purge the extra grease out anyway.