- :
- Plano, Texas, USA
This's not true. If you have 2006 or prior Toyota Sienna the V6 uses timing belt and the water pump replacement would involve timing belt and there's a routine replacement schedule on timing belt. But 2007 and newer Sienna the 3.5L V6 uses timing chain. The chain is an internal lubricated part that does not need to be replaced unless it fails which is not common. With timing chain the water pump is driven by an external drive belt and it's also external. So there is no need to access the chain area. My brother had a 2008 Seinna having original water pump until 150K miles when he totaled the van.Yeah, on our Toyota Sienna mini-van, the water pump was something everyone recommended changing when the timing chain was replaced at 100K miles (part of normal service). The logic was that the water pump generally failed at 120K miles and you actually had to remove the timing chain to replace it. That was a $3500 service at the dealership.
Even if the water pump fails on Sienna, the dealer cost is $600 at the most for watef pump replacement. For 1st-gen CX-9 V6 with timing chain replacing water pump is a totally different story though.