I have started in a new laboratory and they had a lot of preventative maintenance not being performed so I have been running into a lot of problems. My latest is after tracking down a massive air leak I ran a tune - all looked good, not great. Then all of a sudden my peaks went haywire.
I finally figured out no PFTBA in the vial. I refilled and then find out they just filled it 6 months ago - my old lab I never needed to fill the vial in over 8 years. This is a 5975 so the vial is horizontal instead of vertical and when I removed the vial since I have only done this once I couldn't remember if there is supposed to be an o-ring around the collar.
Sorry lengthy post - possibly due to major frustration about lack of documentation and basic maintenance.

I know how you feel, sometimes trying to keep people interested in doing maintenance is a full time job. Had someone last week ask me to look at their 5973 because it wasn't tuning and had air at about 10%. I looked at the autotune they just ran and the EMV was set to 3000V. It was the original EM that was in the instrument when it was installed in 2005!
As for the PFTBA, I believe it does go a little faster in the 5975 because of the way the vial is made. You just can't get as much in there without it overfilling. If there is an o-ring on the vial it should be inside the fitting, either an o-ring or a Teflon ferrule should be there to seal it.
Be sure not to fill it above the horizontal tube or you will be drawing in the liquid instead of the gas from the headspace. Fill a little then turn it sideways to make sure it is not too much.