New Serpentine Belt and Tensioner... 2013 Tundra Still Squealing

Squealing is primarily when I am accelerating and at high speeds (70-80). I got a new belt tensioner about 3 months ago, so took it back to the mechanic and they said I needed a new belt. I just replaced the serpentine belt myself and there is still Squealing. Can anybody point me in the right direction, what could be causing the sound?

 

It has 109k miles, I bought it at about 98k.

 

Depends on the belt you're using. Gator back belts usually prevent squeals as it doesn't trap condensation in the grooves. The original serpentine belts tend to trap condensation in the grooves causing a squeal, you may want to inspect for leaks as this usually happens in the mornings with due, rain fall, condensation among other things...

 

Does it happen all the time? while driving?? only in the morning? only in the afternoon??

 

It happens when accelerating and all the time at high speeds (70-80 mph). No difference between hot/cold or different times of the day.

 

You may have a broken tensioner bolt.... I'll let someone with more experience chime in and correct me, but I broke the tensioner bolt in my Celica a long time ago, and it had similar symptoms the more I accelerated the more it squealed... My engine had to be pulled out since its front wheel drive and the bolt had to be extracted and replaced... The Tundra's may be easier as its layout appears to have more room...

 

What brand Serp belt did you use out of curiosity? OEM or X? The only brand I'd use other than OEM is Gates. Was tensioner OEM?

 

The new belt is Dayco, and I am not sure about the tensioner, firestone replaced it.

 

My new oem (Dayco) belt tensioner lasted 6 months until it started squeeking again. I replaced with a different brand.

 

Dayco's are good but have a tendency to run a bit tight whereas Gates are known to be a better "fit" which means less likely to chirp. Not sure who makes Toyota serps.

 

Gates Rubber used to be here in Denver. Was a huge calibration client for us years ago. I think their serp belt and their very good tensioners are still made here in Arkansas. Dayco's are sourced overseas I think in various places. I'm a fan of Gates.

 

Accelerating and high speeds both require higher RPMs. Can you replicate the noise by raising the RPMs while in park? Or does the truck’s driveline have to be under a load?