looking for some feedback on this. I got a 2017 z51 m7 last november with about 27k miles on it. I had a PPI done and everything came back pretty clean, and no accidents. the engine sounded really good, too. a couple weeks ago, I started hearing a whining/straining noise coming from the engine. at first it was just in lower gears but now I can hear it at idle, too. I took it to the dealership and they said that it's something in the transmission, like bearings or something, and that due to the car's age they didn't want to tear down the transmission to replace the single part and recommended the entire transmission to be replaced. the car is under warranty, and I guess an adjuster is coming out today to determine whether they're going to cover the replacement cost or not. I was told that it isn't uncommon for this and that there's no signs of previous abuse that they can see. But, I'm a bit concerned that if the entire transmission needs to be replaced and there's only 35k miles on it, what other massive repairs might lurking in the near distance? I've never owned a vehicle that had an issue like this so it caught me a bit offguard. I kinda feel like this is one of those things where it's not what most people experience 7 months into having a c7, but then again I may be wrong. I don't run it on a track. I do have a lot of fun accelerating, but I don't think anything that would ruin the transmission - I don't do launches but I do keep the track HUD setting on and often shift when I see yellow shift indicators when accelerating but that's about the hardest I push the car. so should I be concerned about other potential issues, and what should I be looking for if I should be? has this happened to anyone else before and what was your experience with it? thanks -

 

The location of the noises in the front of the car that you're explaining and what they're diagnosing doesn't make sense especially since you're hearing it at idle (you didn't say if clutch was depressed or transmission in neutral at idle). I definitely would have got a second opinion before doing anything with that diagnosis but it sounds like it may be too late for that. These manual transmissions are pretty solid unless you're putting crazy horsepower to them or massive abuse. First things I would have ruled out for a noise like that at the front are number one, the idler pulley - it's a known issue, but the part is cheap. Then rule out any belt driven accessories. Then work your way back - maybe pilot bearing, then throwout bearing, then torque tube bearings/couplers.

Or, maybe I'm losing something in the translation of this story

 

Check you belt tensioner pulley. That's a very common part to go bad and has been known to make noise when it's going bad. If its leaking oil it's a simple $100 part that you can replace yourself. Hopefully it's that simple and not the whole transmission.

 

I like the belt tensioner pulley diagnosis. Very common. Start simple.

 

The M7 trans is pretty bullet proof, I would be concerned that maybe it could be a torque tube noise, and as others have stated the belt tensioner is prone to have a noise that leads to miss diagnosis.

 

What is an PPI? IM Asuming it's some form of report? And how would I get one?

 

Pre Purchase Inspection

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