How kill a "cash cow"

The street talk "why to read the horoscope of a dead child" is true in case of Kerala SRTC. The requirement of the number of buses, the perpetual survey of the density of traffic on specified routes, selecting the right type of bus for that route, and above all the timing of the schedule makes the services successful. Successive Governments, Transport Ministry, political interests never considered these facts but promoted their personal interests. So Kerala SRTC ended up with an abundant number of buses that were more than required and the shortage of buses that was needed suitable to a particular route. To me, it looks like till 2001 they had no choices left except two leading HCV (Heavy Commercial Vehicles) and depending on how much influence one of them had with the Ministry and its minions. Common principles of standardisation which results "on the shelf availability of required parts, consumables, and the ability to negotiate prices, credit payments, scheduled delivery of parts to various depots, the return of parts to the supplier on exchange basis etc were not implemented. The fact is these two manufacturers held in Kerala SRTC captive for many decades and some of the Ministers and bureaucrats helped continue status quo. Consider the following if they were standardised.

Fuel-High Speed Diesel or LSHS (Low Sulphur Heavy Stock)

Engine Oil: SAE 20 W40 Viscosity, 

Gear Oil: API GL-1 to API Gl-5

Brake Fluid. DOT-3 to DOT 5

Coolant: from the gutter water to anti-rust (not antifreeze) 

Fuel, Air, Lubricating oil filters

Tyres

Internal trimming

Batteries

Tyres... many variations like conventional, radial, traction, rolling etc.

And there are many more items that can be standardised for a fleet of over 6000 buses. Did anyone in Kerala SRTC think about it? Even if they knew did they try to implement it and continue to monitor even if the Government, Minister for Transport, the CMD and the CME changes?