PMCS: should the mechanics have to do them for the Grunts in theater?
Hell no, the maintainers are not normally on patrol with the Infantryman, they are responsible for their operator maintenance.
If someone puts the wrong fluids in, they should be responsible for the damages and repairs. If the Soldier does this without training on the vehicle, then I believe it is a shared responsibility between the Soldier and his supervisor that is there with him.
Do the "grunts" pass off their weapon to someone else to maintain?
It is the cornerstone of the Army Maintenance model to have the operators do their level of work..
They use the vehicle, they know what right or wrong with it.
That is of course if they care, or at the least have some sort of "Pride in Ownership" of that vehicle..
If there is a problem with the operator putting the wrong fluid in to a sub-system, I would go and look at the operator training plan..
It has been long said the "Maintenance is Training" and I agree.
Everything we do as a Soldier is a form maintenance...
We as trainees were taught to PMCS ourselves and our gear
PRT is maintenance on the body
Battle Drills, IWQ, and Warrior Tasks are all a form of PMCS that inspect our skill set.
NCOES and CBT are PMCS and Maintenance on our minds..
What should and what does happen are vastly different things...
As for the situation you have laid out.
Mistakes Happen!!!
A new troop I don't think I would push for a statement of charges, but he/she would get a decent lesson from their mistake.
The Commander, XO, and 1SG would be involved in adressing the short coming of that soldier's leaders..
I have had something like this happen a couple of times during my time in the service...
Case #1 Total Cost of Repair $78,000
A seasoned operator during a deployment destroyed the cooling system of an MRAP by adding the wrong coolant to it.
The PSG and PL hid the mistake until the vehicle failed during a mission..
the PSG and PL were relieved and charged..
Case #2 Total Cost of Repair $900
New operator, E-2 less than 1 year TIS, mistook the oil fill for the tranmission on an LMTV for the radiator fill.
That soldier added 2 gallons of water to the transmission.
The soldier was given a bit of corrective training, The squad leader was counseled, and the issue was fixed before damage could happen.
The E-2 in this story reclassed to become a Mechanic.
Being an Inspector, I have many of these stories..