I'm going to tackle changing the lower hose that goes from the thermostat to the engine (and a couple places). It is the one of the passenger side on the bottom (not the lower hose going to the radiator). Looking at the RAVE, and not sure it is answering my questions so figured I would throw it out to all of you:
1. How easy of a job is this, and is there anything big that needs to be moved to get at it?
2. How much coolant am I going to lose? The engine radiator and cooling system is new, so I don't need to do a flush but would like to change it out once this new hose is on so I know I have all of the same coolant brand/type in there.

 

Here is the original picture I took of the spot. I'm pointing to the joint which is cracked. The big hose I'm pointing to connects to the thermostat just off camera to the right.

 

(1) It is pretty easy to get to, you shouldn't have any problems.
(2) You are going to lose ALL of your coolant. If you are running DexCool, you want to refill with DexCool ONLY. If you want to change to green (or another type) coolant, you need to flush your system even though it is "fresh".

 

Make sure you bleed the cooling system really well, otherwise it will overheat if air gets trapped in the external thermostat housing causing it to remain closed.

 

So besides just taking that hose off, is there another preferred route to draining the system?

 

That depends if you want to reuse the coolant or not. If you want to reuse the coolant then use a hand pump to drain the coolant tank first, then remove the top radiator hose and drain as much from the radiator and thermostat side as you can, then go to lower hoses until you reach the point where you want to work. There is no easy way to drain the coolant into a bucket, that would make life too simple.
If you do not want to reuse the coolant then pull the truck onto any surface that you do not care about and pop the bottom radiator hose off.

 

Yep...sounds like another messy garage job! I'll get the drain pans ready!

 

Do the hand pump method in the garage, any other way will flood your garage.

 

I will drain what I could before I open the flood gates!

 

The first time I did it I put a 5 gal bucket under and pulled the bottom radiator hose, coolant went everywhere except in the bucket lol