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Replacing the water pump on a Toyota Sienna before it fails?

The last time my wife took our 2006 Toyota Sienna in for service, the service manager reminded her that the next visit would be the 90,000 mile service and told her that in addition to the belts (timing belt as well as the serpentine belts as called for on the maintenance schedule), the water pump would also have to be replaced. When she spoke with a couple of the mechanics she was advised that this is the dealer’s policy because it (the water pump) may fail in the futute and if it does they will have to charge her for installing another new set of belts including the timing belt.
Needless to say, I am very skeptical about this. I know that water pumps eventually go, but not usually at under 100k miles. I feel that if Toyota water pumps don’t last, then the factory should include the replacement of the unit on the service schedule.
Has anyone else run across this? Any advice is helpful

I agree with you that the water pump should last another 90,000 miles until the next timing belt.

But, changing out the water pump adds almost nothing to the labor charge when they’re changing out your timing belt. The timing belt drives the water pump. So instead of risking that the water pump lasts another 90,000, most people just decide to pay for the extra part now. They don’t want to risk having the water pump last only another 50,000 miles, then they have to pay for all that labor again.

Dealers’ (not factory) aggressive-maintenance policies are often money-driven. You should consult 1) All details of your warranty, 2) Your owners-manual, 3) Factory-Service manual. On the last item, I would go to a different dealer, ask to see the Service Manual on the Sienna without telling them the exact reason or any “leading” information as to why. This service manual may also be available online somewhere. If you are unable to locate independent information on why this replacement is necessary, and at last resort the original dealer refuses to provide such proof, they will either back-down from their position or fail to provide the independent-proof. Then you will know with certainty that this is bogus.

To the best of my knowledge and belief, unless you live in Alaska or Death Valley, as long as you maintain fluids, regular thermostat changes and engine doesnt overheat, the water pump will last well over 100Kmi and maybe twice that. You can prolong the life of the belts and prevent cracking, by applying generous amounts of Belt-Dressing (spray can) just before Winter and also just before the hottest Summer months. I would apply it twice during both periods. The engine should be running during application.

Good luck.

There is no set maintenance interval on water pumps because there is no reliable indicator of lifespan. All moving parts wear and fail. It’s entirely reasonable to expect a water pump to last 100,000 miles. It’s not as reasonable to expect it to last 200,000. If the you replace the water pump now proactively, you’ll be out the cost of the pump plus a small additional labor charge. If the pump fails at 140,000 you’ll be buying a pump, another timing belt, and the labor–plus the cost of towing if needed, inconvenience, and the possibility of engine damage from overheating or timing belt failure.

Knowing that, it’s your car and your money. You are free to authorize the repair facility to replace only the belt or the belt and pump.

Did you ask how much extra the water pump will cost?
Sounds like you went to a dealership.
There’s no need to take an out-of-warranty car to a dealer for this kind of work.
You may find that a good independent non-chain shop can do the 90K service with a water pump for less than the dealer price without the pump.
You can look for a good mechanic here:

The cost/benefit of replacing the pump with the timing belt became very apparent and from about 1990 on I refused to replace a timing belt unless the customer agreed to the complete package including all timing belts, the tensioner and idler pulleys and the water pump and also the cam and crank seals on some engines. It’s funny how some people object to replacing the pump that has no indication of failure but when the pump fails within the year and ruins the timing belt insist that the timing belt is under warranty.

As a consumer, I think it is prudent to go ahead and replace it. Basically you are paying for the cost of the part to insure that it won’t fail between timing belt intervals. By comparison, I just replaced a water pump on my MPV (has timing chain) at 158K miles. If this were a timing belt engine and if I didn’t replace the water pump at that same time, I would be out double the labor, at a minimum.

Your choice, but understand the risks involved.

Although I have only replaced two water pumps since 1956 (on a 1941 Chevy and a 1984 Impala), I agree that the difficult location on many cars with timing belts, the pumps should be replaced at a modest extra cost on those vehicles when the timing belt is done.

I was in an office once in New York, and an electrician was pulling out the all fluorescent tubes from the ceiling and putting them in a garbage bin. I asked the building manager why, and his answer was, “NY electrians are very expensive”, so they extablished a projected time when most tubes would be past their 90% life expectancy, and then replaced them all at once rather than call in the world’s most expensive electricians to replace them one at the time.

In pre-Thatcher England that task would require a licensed, unionized electrician PLUS a helper, an electrician in training. Never mind that in the US the average housewife or teenager knows how to do this without help.

A fleet customer with many vehicles had 6 vans that were driven in 2 shifts up to 600 miles each day by female college students carrying aging, invalid patients. We kept the vans running without a failure for years and each had in excess of 300,000 miles when they ended the program. It is amazing how reliable a vehicle can be if properly maintained.

At 90,000 miles on my 2002 Sienna, Toyota recommended INSPECTING the water pump when replacing the timing belt, and it was good. At 180,000 miles, they recommended replacing it.

Much will depend upon maintenance. If you have been pumping sludge and acid in your cooling system, your water pump should be replaced. If you have kept good coolant in it, then an inspection by a qualified mechanic who does not have a prejudice that all pumps on all makes must be replaced, will suffice.

That is on Toyota, I make no such claim on other makes.

Although I agree with changing the pump at the same time as the belt, let me ask a different question:

How many times has a replacement pump failed prematurely? Of those times, how many pump failures took the timing belt with it, and then wrecked the engine?

Any real difference between OEM pumps and aftermarket?

I have seen 2 replacement pumps fail prematurely. Both were branded as “new,” not rebuilt and were Chinese imports sold at McParts stores. As a matter of fact, they were both the same part, fitting the Cadillac 4100 engine.

Flip of the coin. I think most last to the next timing belt change or typical ownership period somewhere between 100k-150k miles.

C60- BELT DRESSING!?- yes I’m shouting, I have a can of belt dressing around somewhere only because I haven’t bothered to throw it out, but I certainly haven’t used it in 30 years and absolutely wouldn’t;t use it on a timing belt.

OK, this happened to me with my 1998 sienna. I replaced the timing belt at 89k miles. in 2016 I replaced the timing belt at 169k miles because I knew it was getting kind of old. I asked the dealer about replacing the water pump before they changed the timing belt. They never said I should replace the water pump, or any of the idlers or pulleys. This was the oldest Toyota I ever had, with the most miles. I regularly changed the coolant. I was over-confident.

Less than a year later an idler and water pump failed. Maybe the water pump leaked, and ruined the idler pulley. They wouldn’t take responsibility for it. That was a $900 mistake. I don’t know why they didn’t advise me to replace it. They will lose my business in the future because of it.