Serpentine belt lifespan

I have a 2014 Dart 2.4 with 105,000 miles and original serpentine belt.
On previous cars, I’ve inspected the belt and replaced when it looked tired and cracked.
I can’t even see the belt on the 2.4L to inspect mine!
Internet searches peg the belts usage as being 50-100,000 miles so I guess I’m pushing it and should replace?

Can you see it from the bottom looking up? They are cheap so no harm in replacing it ahead of time.

after changing one, i always toss the old one in the car just in case something "stupid or weird" happens on the road.
those belts also work good for lifting things at times around the shop.

I'm not familiar with the 2.4. Are we talking about an accessory serpentine belt, or is it the timing belt?

The car has an aerodynamic panel under it which makes seeing the underside of the engine compartment impossible without removing it. I’ve never tried as unlike my Challenger, they at least put access hatches in it to get at the oil plug and to get at the oil filter.

This is the accessory belt which is on the passenger side and blocked by several components such that you can’t even see it.
The engine has a timing chain so I shouldn’t have to worry about that.
I looked at several YouTube videos and replacing this 2.4 serpentine belt looks like a major pain. The air cleaner box must be removed and maybe the coolant reservoir also. The area between the pulleys, tensioner and frame or inner fender is very tight. And to add insult to injury both videos I saw they had to support the engine with a floor jack then remove the passenger side motor mount to get the new belt in and installed.
I thought I’d seen something a couple years ago instructing the tech to do this job from underneath and maybe that’s the trick, but I don’t find any mention of that now.
The reason I’m thinking about this now is I’ve got a coolant leak and scheduled to take it in next week to get that addressed. I’m not going to work on the car outside when it’s bitter cold and snowy, so taking it to a local trusted garage seemed the thing to do. I’m just thinking as long as it’s in maybe I should ask them about replacing the serpentine belt.
From what I’m seeing in those videos it’s not a job I’m eager to tackle myself in spring, and if they’d do it in around 1-1/2 to 2 hours maybe best to bite the bullet and get it done rather than forget about it until the belt snaps someday while I’m driving on the highway?

Personally, I'd definitely be replacing along with tensioner and idler.

what are you waiting for

It's time for replacement but I wouldn't worry about it snapping. I've seen those things shredded but not broken. They are tough!! We use them to hoist cast iron blocks so as not to worry about chains falling in bores and scratching them........never saw one break....including picking up BBM and BBC iron blocks.

Better to have it done when the coolant leak is being addressed; might end up working in the same area, too.
I've had them last a LONG time, but 100K is plenty of luck IMO.

I seem to remember 100k when they first came out but that was a while back. Does the service manual or maintenance schedul say anything about replacing it ?

I don’t have a service manual for the Dart and don’t recall seeing anything about it in the owners manual.
I was under the hood this afternoon adding some coolant before the snow hits tonight and bitter cold tomorrow, and took another look with a flashlight while there.
Seriously what I could see of the belt looked nearly new. I remember changing serpentine belts on my Ram 5.9 and a Ford 3.8 years back after seeing the inner ribs were cracked. The ribs on my Dart looked pretty good.
I guess I’ll talk to the manager of the garage next week when I take the car in for his opinion.

Here ya go:

1. NEVER! Replace an Alternator Belt/Serpentine Belt AGAIN !

https://www.youtube.com/watch?v=dRXkt6Dgi4k

2. How To STOP ALTERNATOR BELT Squeaking & Chirping Noise FOREVER!!!

https://www.youtube.com/watch?v=_8RE8p_m8bA

3. STOP Replacing TIMING BELTS....PERIOD!

https://www.youtube.com/watch?v=yY6dduFcRvI

4. How To Make Wiper Blades and Alternator Belts LAST FOREVER

https://www.youtube.com/watch?v=oG8NIMStjLs

Serpentine belts will start cracking on the inside ribs when they get old. Personally in 40 years in the auto repair business the only time I've seen one break is when you have a tensioner or pulley bearing failure.
Doug

My cars don't see a lot of mileage so the only time I replace serpentine belts is when they are cracked in the ribs look badly worn from the back or if they're stretched beyond the wear marks on the tensioner.
The only time I've replaced tensioners or idlers is when there is a lot of movement from the tensioner or the pulleys make noise or have play in them.
And I also usually thow the old belt in the trunk just in case like fan belts on older cars but I've never needed it. Of course the one time you do if it throws it or it shreds it wont be there.

I think at 100,000 it's hit is lifespan according to the books. If it is a pain then replace it when the coolant leak is being fixed.

That being said I have never had a serpentine belt fail unless something else was bad too. Like has been said they are tough. I have run them with wear on the backs and cracked ribs underneath for years and they did fine. Would I tell anyone to do it, no, but on my car and I have the ability to swap it out in a few minutes I often place my bets and roll the dice. On a clients car I suggest they replace them when they look worn or cracked.

It has been my experience when they fail there is something else wrong. If it jumps off or shreds it is usually a pulley out of line or a bad bearing. If it jumps, replace it. It usually stretches the belt in an odd way and damages the internal belts in the belt. They have belts like a tire and like a tire with bad belts it will be short lived in this world.

Hopefully it won't cost much to fix.

It looks like a tough job based on what I see on YouTube videos, passenger side engine mount has to be removed to get at the pulleys.
Perhaps it can be got at from underneath but since the car has this big aero panel mounted under the engine compartment I can’t tell.
Coolant appears to be leaking around the upper radiator hose inlet which is on the drivers side. Hopefully a fairly straightforward job, maybe just the hose, out in the driveway with it snowing every other day and below zero I’m sol dealing with that problem myself. Like a wheel bearing that went bad on it a few years ago, this car rarely has issues but when it does it’s in the dead of winter!
I did dig out the owners manual today and no mention on serpentine belt replacement intervals.

I hope you can get everything fixed and squared away. Serpentine belts are definitely a PITA (by design) to replace on any modern vehicle. I went through it when the '06 2500 (Cummins) AC compressor seized up and burned up the belt. Although it didn't help in this case, i keep a spare belt under the rear seat.

I dropped the car off yesterday morning and asked them about the belt. They said they'd check it. I thought he mentioned some sort of gage they use to check belts? Would that be to check if it's gotten stretched?
I haven't heard back from them yet, I hoped they'd get the car fixed and I could pick up before the snow. Oh well....