2005 Prius Hybrid Coolant change at 45k?

No way. That's way, way too early... Tell him to prove that that's what Toyota recommends.

The FIRST coolant changes are scheduled on toyota USA.com at 100,000 miles!!

 

Hi Brian,

Its not reasonable unless the coolant was contaminated. As Fibb indicated, 100K miles is the US change interval for the factory-fill coolant; subsequent refills are to be changed at 50K mile intervals.

 

Had the shop suggested changing the transaxle fluid, that might be a good plan.

 

Seems very good to me. You cannot go too wrong replacing that for $120 because its almost 4 years old and that coolant in the inverter is the heart of the hybrid system. Waiting on 100K change out is way to long. Thats almost 8 years on average driving. I will change my 07 out at 4 years old also at least. I'm running this product in my 07 Inverter coolant now:

http://www.redlineoil.com/whitePaper/21.pdf

Excellent aluminum corrosion inhibitor.

Inverter coolant replacement is not a do it yourself because of the special evacuation needed to purge air out of that fluid system.
If I was you I would have them change the trans fluid also. Then you will have another 50,000 miles of worry free motoring ahead of you. Probably $250 total. Every 4 years $250 is cheap cheap. Money well spent. Keep clean oil & fluids in a Toyota and it will run forever.
Lots of posts lately of failed Inverter coolant pumps. Not sure why they fail. Fatigued coolant? Poor quality pump? I do know when the pump fails the Inverter overheats...and since it has no temp sensor no warning's are thrown till the Inverter fails. Out of warranty its about $5000. Even in warranty I'd hate to roll in a 2005 on a flatbed truck with a failed Inverter to the same dealer I didn't have the INVERTER COOLANT SERVICED by.
Just sayin'.

 

Too frequent changes of car fluids is an unnecessary burden on the environment. Don't do it.

 

I helped another owner change both the engine coolant and inverter coolant at around 80K miles. By visual inspection both coolants looked like new. No debris or other contaminants visible. If it was poured into a punchbowl you would not be hesitant about drinking it (but of course you would not want to drink this highly poisonous fluid).

Still trying to figure out why the service interval for subsequent changes is 50K miles. My guess is that the shorter interval is due to the expectation that some old coolant will remain in the system, so Toyota wants the mixture of old and new replaced more frequently. For example, the engine coolant capacity is 9 qt but after opening all three drains (engine block, radiator, CHRS canister) I could only get 6 qt of old coolant out. Therefore after new fluid is added you end up with 2/3 new, 1/3 old.

 

Patrick, did you check the specific gravity or do a chemical analysis? The reason most coolants need replacement is that they lose the substances in them that prevents freeze and boil. Although they look perfect, their specific gravity will measure wrong and they won't do the full job they claim. That's my understanding and I do test mine and see the SG change with old radiator punch.

 

Hi Steve,

I did not check the specific gravity since the owner wanted to have the coolant changed early. I do have one of the plastic gauges with a rubber squeeze bulb intended for that purpose.

 

Yesterday, went to the Toyota dealership to have the "maintenance required" light checked. The receipt says "inverter coolant completed" and "performed hv fan service and instated new filter." Total charge $400. Now going thru all the posts, it seems that the recommendation for inverter coolant is at 100-150k miles. Mine is 37,550 -- nowhere did I see any evidence of a leak. Is it hasty to assume that the dealership upsold me?

 

It is not hasty to make that assumption, and if you look at the inverter coolant reservoir you will see a sticker which indicates the factory fill coolant should be replaced at 150K miles. It is not likely that the HV fan needed service unless you have unusually furry pets shedding hair in the back seat area.

The "MAINT REQD" light operates on a 5K mile odometer timer. The engine oil and oil filter should be replaced at 10K mile intervals (or sooner depending upon personal preference.)