Why I Compare the Cat 320 and 336
As a quality/brand compliance manager at a construction equipment dealership, I review every machine and attachment before it reaches customers—roughly 200 items a year. I've rejected about 15% of first deliveries in 2024 due to spec mismatches. So when contractors ask me which excavator to buy, I don't give them a sales pitch. I give them a comparison based on what I've actually seen on the lot and in the field.
The two most common models people ask about are the Caterpillar 320 and the Caterpillar 336. Both are part of Caterpillar's excavator lineup, but they serve different needs. I'll compare them across five dimensions: performance, fuel efficiency, maintenance and parts, operator comfort, and total cost of ownership. At the end, I'll tell you which one I'd pick for different scenarios.
Dimension 1: Performance and Capability
Let's start with the numbers. According to Caterpillar's published specifications (caterpillar.com), the 320 has an operating weight of about 22,600 kg (49,800 lb) and a net power of 162 hp. The 336 is significantly larger: around 36,000 kg (79,400 lb) and 275 hp. That's not a small difference—it's like comparing a pickup truck to a dump truck.
In terms of digging force, the 336 wins hands down. Its bucket digging force is roughly 30% higher than the 320's. If you're working in heavy clay, rock, or dense material, the 336 won't bog down. The 320, on the other hand, is more nimble. I'm not a hydraulic engineer, so I can't speak to the pump design, but from a quality perspective, the 320's cycle times are faster in light-to-medium soil. It's actually pretty impressive for its size.
One thing I've learned: don't assume a bigger machine is always better. We had a contractor who bought a 336 for a residential project. He couldn't maneuver it between houses. He ended up renting a 320 for the tight spots. So match the machine to the job.
Dimension 2: Fuel Efficiency and Operating Costs
Fuel is where the 320 shines. I don't have hard data on exact gallons per hour because it varies by load and operator, but based on our fleet records, the 336 burns about 2-3 liters more per hour than the 320 under similar conditions. That doesn't sound like much, but over 1,000 hours a year, it adds up.
However, the 336 moves more material per hour. So if you calculate cost per cubic meter moved, the gap narrows. I wish I had tracked this more carefully from the start—we only began logging fuel data in 2023. What I can say anecdotally is that for heavy production, the 336's productivity often offsets its higher fuel burn.
Here's a real example: In Q1 2024, we ran a side-by-side test on a road project. The 320 moved 120 cubic meters per hour; the 336 moved 210. The 336 used 18 liters per hour, the 320 used 15. Cost per cubic meter: 320 was $1.80, 336 was $1.54. So the bigger machine was actually cheaper to run on that job. But on a smaller site with lots of stops and starts, the 320 won.
Dimension 3: Maintenance and Caterpillar Body Parts
This is where my quality inspector hat really comes on. Both models share Caterpillar's legendary reliability, but they don't share all their parts. I assumed the 320 and 336 used the same bucket teeth and filters. Didn't verify. Turned out they don't. We had a batch of 320 teeth that sat on the shelf because a customer with a 336 ordered them by mistake. That mistake cost us about $1,200 in restocking fees and delays.
So when you're looking at Caterpillar body parts, always check the model-specific part numbers. The good news is that Caterpillar's dealer network is excellent. Parts availability is usually 24-48 hours for critical components. The 320 has slightly cheaper consumables—for example, a set of teeth runs about 15% less than the 336's. But the 336's parts are built to handle more abuse, so they may last longer.
One more thing: if you're considering aftermarket parts, be careful. I've seen third-party parts that claim to fit both models. They don't. We rejected a shipment last year because the tolerances were off by 2mm—enough to cause premature wear. Stick with genuine Caterpillar parts if you care about uptime.
Dimension 4: Operator Comfort and Safety
Both cabs are comfortable, but the 336 has a slight edge. It's wider, with more legroom and a better seat. The 320's cab is fine for a full shift, but if you're running 10-hour days, the 336 reduces fatigue. I've had operators tell me they feel less beat up after a day in the 336.
Safety features are similar: both have rearview cameras, ROPS/FOPS, and optional 360-degree visibility. The 336's larger size means you sit higher, which gives a better view of the trench. But the 320 is easier to transport without a permit in some regions.
Speaking of safety, if you're wondering how to get forklift certification, that's a different topic—but it's a good reminder that operator training matters more than the machine. A skilled operator on a 320 will outperform a novice on a 336 every time.
Dimension 5: Total Cost of Ownership
Let's talk money. The 320 typically costs around $180,000 new, while the 336 is closer to $320,000 (based on dealer quotes as of January 2025; verify current pricing). That's a big gap. But total cost of ownership includes resale value. Caterpillar excavators hold their value well, but the 320 has a larger buyer pool because it's easier to transport and cheaper to own. The 336 appeals to a smaller market—quarries, major earthworks, and mining.
Looking back, I should have paid more attention to resale data earlier. At the time, I was focused on upfront price. If I could redo that, I'd build a 5-year TCO model. But given what I knew then, my advice was reasonable: if you have steady heavy work, the 336 will pay for itself. If your jobs vary, the 320 is more flexible.
One more thing: don't forget about attachments. A hydraulic thumb or breaker can add $15,000-30,000. The 336 can handle bigger attachments, which opens up more revenue streams. But the 320's attachments are cheaper and easier to find used.
Which One Should You Choose?
Here's my take, based on years of inspecting these machines:
- Choose the Cat 320 if: You do residential, light commercial, or utility work. You need to move it between sites frequently. You want lower upfront cost and fuel efficiency. You're okay with slightly less digging power.
- Choose the Cat 336 if: You're in heavy construction, mining, or quarry work. You need maximum productivity and can keep the machine busy. You have the budget for higher purchase price and maintenance. You want the best operator comfort.
And if you need something else entirely—like an italics generator or a pool pump—well, that's outside our expertise. We focus on Caterpillar excavators and their body parts. That's what we do best. I'd rather tell you we're not the right fit than sell you something that isn't.
Remember, the best excavator is the one that matches your job, your budget, and your operators. Don't let anyone tell you there's a one-size-fits-all answer.
