2009 Prius: drive belt question

Well, took the Prius in to the dealership for the cooling pump recall. When I got the car back, the guy at the desk said gave me their usual multipoint inspection printout, but this one said Red Warning! The drive belt is cracked and needs to be replaced ($140). Took it to a local garage, and told them I couldn’t see any cracks (it’s deep in, but I can see a couple of inches of the inside of the belt as well as the outside. They couldn’t either, and said it looked fine, but if I wanted to replace it as preventative maintenance that would be reasonable and what he would do himself were it his car($77). I took it back to the dealership for its 90k checkup, and got a printout with Green next to “drive belt.”
I saw an old posting by Tom & Ray, which said that 90k on a Prius is not 90k on the drive belt as it is not always running. So. Should I replace it? Does the “multipoint inspection” not really include inspection of the drive belt, or was the prior recommendation made on a better view, or solely based on mileage (or business practices)? I checked again with a strong flashlight, and could see one hairline crack in the outer rib. Don’t know if it matters, but I live outside of Boston, the car spends some of its time in an enclosed garage but has spent nights in the cold and days in the sun.


Forget about the fewer hours the hybrid motor runs. If there are any cracks, replace it. If the manual says to replace it, and now is time, replace it. If it’s in great shape, leave it in.

It can’t be determined if a serpentine belt requires replacement by visual inspection anymore. In the past serpentine belts were made from neoprene and these belts would crack/chunk out indicating replacement was required. But serpentine belts today are made from EPDM. This material doesn’t crack/chunk out when it’s worn. It just wears out.

You can get a free belt belt wear indicator for these EPDM belts. http://www.autotrade.ie/index.php/gates-launches-accessory-belt-drive-system-wear-indicator/3468

So just because the belt shows no cracks doesn’t mean it’s not worn out.


Remember what Tom and Ray say… The cheapskate always spends the most. Why such anguish over a few bucks? Let it break in a bad neighborhood or drive it with a broken belt will be way more expensive.

Thank you - that was quick. Tester, I’ve ordered my belt wear indicator, and the website (and your post) were informative.

Texases: The manual says to start inspecting the belt for wear starting at 60k, then every 15k thereafter, nothing about a suggested time for replacement.
I will go ahead and replace (might try to do myself after seeing the video on youtube).

I am still curious why the same garage (not necessarily the same mechanic) that said I needed to replace the belt now says that it is fine…

" I am still curious why the same garage (not necessarily the same mechanic) that said I needed to replace the belt now says that it is fine… "

Not all service recommended to customers is the result of a thorough inspection. Some service items, particularly ones that are fairly easy and don’t require much time, but are lucrative for the technician or the business in general, are sold as normal routine. The technicians and the repair facilities have to make a profit in order to remain in business.

I’m not saying that anbody is dishonest, but this should cause one to be a bit more skeptical when having a car serviced. You are probably better served by servicing the vehicle according to the manufacturer’s service schedule.


Common sense: Alas, the maintenance guide just says “inspect” from 60k to 125k (the last scheduled maintenance in the guide). Some of the internet postings suggest replacement at 100k; if that’s a good guide, then I have a little time to order the parts. Others have done it earlier, but blame it on living in the desert.

KRiley: Good point, if the drive belt is like a timing belt, replace 10k miles early. On the other hand, I wouldn’t buy a brand new battery right now to avoid the chance of it fizzling out, not when people get plenty more than 90k miles out of the original. Or maybe I should…