I'll help to the best of my ability.
Keeping All parts in availability for a vehicle is only required Bby law as long as a warranty period in in effect. Look at ford for instance. Over the last 10 years with Toyota, I've noticed that for the most part, toyota tends to keep stuff around for an unusually long length of time compared to other manufacturers. I know I can still get parts for FJ40 cruisers. There are also cars that the parts dropped off of a little more rapidly such as the Corolla FX and other short lived models. It's really a matter of demand for the part. High demand means it will stay around a while, as no demand means it will phase out faster. Interior componants like trim usually will disappear in color but stay around in gray for a while as well.
I couldn't find the official statement regaurding mixing of the coolants, If you mix, you will have to use the properties and intervals of Toyota Red coolant. Mixing Toyota red into Pink is OK if you dont mind the downgrade in lifespan of the coolant. You can go UP from red to pink but if your vehicle is older then 04, you still use the timetable for red coolant for your intervals. It's common to see people top off red coolant with pink since they don't have to add water.
We don't change the idler or tensioner when we do timing belts unless there is a reason to do so as replaceing them all would be an extra expense that not every customer needs to take on. Water pumps and drive belts are treated the same way. We generally keep "most" tensioners/pumps and belts in stock in case they are needed. Every dealer has a different practice for stock levels and parts they keep "on hand".
I hope this helps as i know it's not the 100% definate answer you were looking for but hopefully it's a good solid start.
Keeping All parts in availability for a vehicle is only required Bby law as long as a warranty period in in effect. Look at ford for instance. Over the last 10 years with Toyota, I've noticed that for the most part, toyota tends to keep stuff around for an unusually long length of time compared to other manufacturers. I know I can still get parts for FJ40 cruisers. There are also cars that the parts dropped off of a little more rapidly such as the Corolla FX and other short lived models. It's really a matter of demand for the part. High demand means it will stay around a while, as no demand means it will phase out faster. Interior componants like trim usually will disappear in color but stay around in gray for a while as well.
I couldn't find the official statement regaurding mixing of the coolants, If you mix, you will have to use the properties and intervals of Toyota Red coolant. Mixing Toyota red into Pink is OK if you dont mind the downgrade in lifespan of the coolant. You can go UP from red to pink but if your vehicle is older then 04, you still use the timetable for red coolant for your intervals. It's common to see people top off red coolant with pink since they don't have to add water.
We don't change the idler or tensioner when we do timing belts unless there is a reason to do so as replaceing them all would be an extra expense that not every customer needs to take on. Water pumps and drive belts are treated the same way. We generally keep "most" tensioners/pumps and belts in stock in case they are needed. Every dealer has a different practice for stock levels and parts they keep "on hand".
I hope this helps as i know it's not the 100% definate answer you were looking for but hopefully it's a good solid start.