I have had the gatorback belt on my car (17% pulley) for like 15k miles and I can barely see the hole on the tensioner, which surprised me (I don't track the car, occasional red-lining) I don't hear any pig squeels or anything unusual.. how do you exactly feel / hear the sc belt slipping / strectching??

Are the lifespan of the gatorback belts shorter than NAPA belts? I am debating which belt I should get this time

 

Gates Belt, haha

I've had 2 NAPA Belts, both used with my 19% pulley. I'm now trying a Gates K060532 that should get here Friday.

 

When the belt was still new, were you able to see at least one full hole in the tensioner?

 

Nope,
Half hole at the most with brand new belt.

 

Seems like you're belt tensioner is going to 'go' soon.

 

Or alternately, the OP's Gatorback belt was too long for the application. If the belt was showing only half a hole new, and after 15K miles the tensioner hole is barely visible, then there is probably minimal stretching, though there could be some slippage.

If the current belt looks okay (ribs are intact, no shredding) and as the OP states, there is no squeaking or rattling from the tensioner, I don't believe that the tensioner is giving out - the belt has just stretched out from use. However, due to the stretching, there may be some belt slipping and the car's not making as much power as it can with a tighter belt. Not making optimal power would drive me nuts, but for most people, there's probably room for another couple thousand miles. Ideally, at least one hole should be showing in the tensioner, so choosing a shorter belt may be something for the OP to consider.

 

I agree, but, he could only see half a hole with the brand new belt. I bet he's going to need a new tensioner soon...

 

I certainly won't dispute that the OEM tensioner is awful and likely to fail!

That said, it seems that the use of shorter belts for 15% and more SC reduction pulleys is a more recent trend. Wouldn't surprise me if the Gatorback belt currently in the OP's car is close to stock length to begin with, which may also account for showing only half a hole when new. Hopefully, the tensioner won't need to be replaced. The OP should be able to find out the part number of the Gatorback belt used and shed some light.

 

In my experience, Gatorback belts work very well with smaller pulleys like 17% and 19%, however they do stretch over time. Napa belts will stretch a certain amount right away and then stay there for a longer time.

 

Thank you for the feedback, sir. From your experience, I'm gathering that:
1. Gatorback belts will require replacement with a new belt more frequently (10K to 15K miles) to account for the stretching occurring over time.
2. With NAPA belts, find the tightest new belt that will fit over the pulleys to account for the initial stretching.