Check the Dang Tensioner!!

[LXstatic]

Note to self, when replacing the serpentine belt on the 5.7 be sure to check the tensioner while you're in there. I recently had the belt replaced on my wife's LX and took a road trip to Nawlins. It did great all the way down there, parked it for the weekend and on the way back 10 miles north of NO I heard a ticking noise and then a big hiss. Pulled off the highway and saw 1/3 of the belt had come apart and wrapped around the fan shaft and the a/c compressor clutch. Then noticed the a/c freon line had been damaged, FML!! Luckily there was enough belt to keep it running all the way back to Mempho. Since my return, my mechanic has installed the new tensioner and belt and now I am waiting for the only a/c line in the country to arrive from Cali, then a freon charge... Please let this be a warning to always check the dang tensioner!! What was a $100.00 belt change has snowballed to near $600.00, smh.

 

[biphnest]

More details please... How many miles were on the new belt before it failed? What brand and part number was the new belt? How many miles were on the tensioner before it failed? Where you able to personally inspect the failed tensioner? Did the mechanic also inspect the idler pulley?

 

[bloc]

FYI if you do some digging most cities have shops that can install new rubber sections into AC lines and even repair damaged metal lines.

But yeah I have new tensioner/idler/fan bearing bracket on the bench waiting for some good weather for install. At 150k now and hope to avoid a failure like yours.

 

[OregonLC]

Hard to tell what has been done already on the truck. It's a 2015 so the miles are likely not that high. But one might also consider doing all rotating parts 'while you're in there'. Tensioner, idler, fan bracket, water pump. Do those along with the belt and you should be good for another 100K.

I added the alternator to the list of proactive repairs because a) mine gets submerged and b) it's a royal mother bear to get to. The time to do it is with the radiator out. It's a $320 insurance policy against later pain.

 

[LXstatic]

More details please... How many miles were on the new belt before it failed? What brand and part number was the new belt? How many miles were on the tensioner before it failed? Where you able to personally inspect the failed tensioner? Did the mechanic also inspect the idler pulley?

I had the belt replaced right before the trip... Toyota belt part # 90916-02680. So, approx. 395-400 miles. The LX is a 2015 with 53k on it. Seems a little weird that the tensioner failed that early, but after some more looking the tensioner was causing the belt to move forward toward fan, etc. Not sure about the idler, I will check. Thanks!

 

[Sandroad]

I had the belt replaced right before the trip... Toyota belt part # 90916-02680. So, approx. 395-400 miles. The LX is a 2015 with 53k on it. Seems a little weird that the tensioner failed that early, but after some more looking the tensioner was causing the belt to move forward toward fan, etc. Not sure about the idler, I will check. Thanks!

Your further description points to the possibility of a faulty job installing the new belt. Few (none?) tensioners fail that early and the tensioner usually wrecks the belt by locking up the bearing and not by causing the belt to move around. And, with a failed bearing the remainder of the belt would not have lasted until Memphis. Did you inspect the failed parts?

 

[OregonLC]

Yeah, I'm thinking what @Sandroad is. It's not the easiest job to get that belt on with everything in place. If one of the grooves were running on the rim of the pulley because it wasn't seated properly I could see how it could cut through it. Getting it installed correctly requires some care and force.

Or they left the holding pin installed... But if that were the case doubtful you'd have power steering, at least not without a ton of squealing.

 

[OregonLC]

FWIW, here’s the part. At 135k mine was still highly serviceable.

 

[LXstatic]

Your further description points to the possibility of a faulty job installing the new belt. Few (none?) tensioners fail that early and the tensioner usually wrecks the belt by locking up the bearing and not by causing the belt to move around. And, with a failed bearing the remainder of the belt would not have lasted until Memphis. Did you inspect the failed parts?

HMMMMMMMM.... and no, I did not see the tensioner...

 

[biphnest]

LXstatic -

From your description of what happened (including the fact that the new belt failed after only 400 miles)... I'd say that the belt failure likely causes are: 1) Damage to the belt during installation (as might happen if the mechanic used a screwdriver to pry the belt into place rather than releasing the tensioner pulley spring tension, 2) Damage to the belt on initial engine start-up due to the belt not being properly centered on all of the pulleys during installation, 3) A defective belt from the factory, installation of a used belt, or installation of a poor quality after market belt (or maybe even a counterfeit belt).

Anything is possible. It's hard to figure out without inspecting the defective parts and talking to the mechanic.

A worn tensioner pulley will usually loudly squeak and squeal long before it would fail in a way that damages the belt.

It's possible that your mechanic is on the hook for the repair cost.