SQUEALING NOISE 2016 Pete 579 MX-13

I'd start with the intake system. Check every single rubber boot and pipe from the turbo outlet to the intake manifold. Maybe get the ATA pressure tested.

Check the exhaust system for leaks, usually leaks that make noise will be between the head and the turbo but check the whole system. Should be easy to see a leak, it'll leave soot trails. EGR system could be another possible culprit. I'm not at all familiar with the MX but again, look for soot trails or evidence that gasses are escaping.

 

I’d say check air to air.
or these pulleys are bad about weird noises on paccar

 

Tensioner gets weak over time and the belt will squeal under load. Does not matter that the bearing in the tensioner is good and rolls smooth. With the truck running see if the tensioner is moving such as vibrating, it should be steady, if not it is bad. Check what AModelCat states in post #2.

 

Yup this crap right here has happened about 3 times in my rig tensioner or a roller rolls smooth but is so worn out it starts to squeel.

Also may be worth checking the EGR valve. If its clogged in the tube it can get stuck partially open and makes that wonderful sound as well and if left for a while can cause the spindle to snap off requireing a new one...which has happened twice in my rig so far lol.

Finally another place ive had make that noise is the inlet pipe to the SCR. That seal can go bad and begin to leak especially if the filter is begining to plug and causeing a lot of extra pressure. Wont throw a check engine either until its about to blow.

Otherwise amodel covered everything. Oh as an after thought, check this tensioner in particular. It is the bane of my bloody existance. I had a streek of 8 of these go bad in a month due to poor manufactureing causeing them to just die on me and it tends to fail every 100k miles or so on MY engine, even though thr factory one went to 600k. Worth looking at anyway.

 

The tensioner pivot is a POS. The idler bearing is fine but alignment gets off. But AModelCat is dead on for my MX13 (2016), pivot shaft on EGR valve got egg shaped and would whistle under boost. After all repairs, one of the charge air boots would squeal and finally sealed up after a day or so. Stay at it.

 

The scr seal is where the pipe goes into the back of the SCR. I dont have a part number handy sadly its on my repair paperwork sitting in its box back home. But just have pete do an exhaust leak test. If its bad you will see soot or it will ROYALLY fail a spray test. As for the tensioner just get the paccar one from them directly. It usually ends up lasting to 100k. The knock off ones are poorly built garbage.

But dont take ANYTHING on my truck as "normal" anyone here can confirm if there is such a thing as a cursed truck. I have it in spades lol. Also if you are doing an EGR clean have them do a full clean on the emissions system, and have them pull the pipes and run a brush through them where they can. It costs a lot more but soot likes to collect in those elbows. If you EGR is shot have them make sure its the new style one and if not upgrade to it. The old style on the epa 13 engines was pretty unreliable and caused issues since some moron decided that using pressure fitted mild steel spindles know to heat up and deform letting the flap basically spin freely was a GREAT idea.

 

I bought a OEM Paccar replacement EGR valve, pricey but I don’t like doing things twice. There was absolutely nothing wrong with the valve except the pivot bores It appears to be silver brazed together and hard to disassemble While I had it apart I put on a PDI exhaust manifold and am quite pleased with the result. It doesn’t have any more power but definitely has more grunt and considering what a weak motor it is, that’s an improvement for me.