Cracked Track Bushings

Hey everyone!

I was just adjusting the track tension on my 311CU and spotted some pretty bad damage. I've got maybe 3-6 cracked bushings on each track, plus one spot where a chunk is actually gone. It all looks like it's been like that for a while—probably was already there when I picked up the machine last fall. I've got a few questions about what to do:

1. If I keep running it through the rest of the year—maybe 200 more hours—what kind of risks am I looking at?
2. Would you all replace the whole link assembly and drive sprockets too, or just swap out the cracked bushings?
3. For getting parts, should I stick with Cat or are there decent aftermarket manufacturers out there?

I'm pretty new to this heavy equipment stuff so any advice would help a lot. Thanks!

Back in 2017 I had a bushing explode on our 2004 Hyundai 210 while we were testing it. This happened at -13c in Kamloops—the Finning dealer had picked up the machine from the city of Kamloops as a trade-in. It had a brand new undercarriage at the time, and I think the cold weather might've pushed it over the edge. That's been 10 years now and we haven't had any other track link bushing failures. The machine has walked at least 120km since then across various mining claims, and that failed bushing hasn't caused any problems.

What brand of track chains do you have? You should be able to see some branding on the rail links. Maybe post a photo of your sprockets too—I'm just an owner/operator, but other folks here might spot something from the pictures.

Your track chains are probably done for. Can you post some pictures of the rest of the undercarriage? You'll likely need to replace the sprockets and rollers too. If that's what you're looking at, I'd say as long as you can keep the tracks from coming off, running it shouldn't cause damage to anything else. I haven't had good luck with ITR parts myself, though some people seem to like them. If Cat parts aren't a whole lot more expensive than aftermarket options, OEM probably makes the most sense.

Looking at the photo, there seems to be quite a bit of internal wear on the pin. Are the pin bosses wearing where they contact the lower rollers?

I wasn't totally sure what I was looking at, so I'll grab some better photos when I'm back on site. I'd like to keep running it since it's on a job right now, but I'm worried about the tracks coming apart, damaging something else, and getting it stuck somewhere I can't easily deal with.

Do you know how many hours are on the machine, and when the undercarriage was last replaced? What kind of work are you running it for?

Not sure exactly how many hours, the hour meter's stuck at 1911, but I'd guess somewhere around 3-4k. Pretty confident it's all original undercarriage.

Yeah, it might hold up fine for a while longer. If you're not pushing the machine too hard on the undercarriage, you could probably make it through the rest of your work. Just keep an eye on it and try to avoid anything that's going to put extra strain on those links.

Roger that.

I've got some more photos of the undercarriage here. Everything seems okay to me but I'm not really sure what I'm looking at, so let me know what you think.

Did you pick up the machine brand new from a Cat dealer? There were some factory problems that dealers could handle under warranty. A bunch of excavators ended up getting new tracks because of issues like yours. From what I can see in the photos, your other components look fine. I'd recommend calling your dealer's PSSR department to come out and measure your undercarriage so they can tell you what needs to be done.

No, I picked it up used, but I think the chains might be original. I'll reach out to them about it.