Cat 308 CR vs Cat 320: The Short Version
The Cat 308 CR and Cat 320 answer different excavation questions. The 308 CR is an upper-end mini excavator for tight access, utilities, landscaping, rental fleets, and attachment work, with 69 hp net power, 20,771 lb maximum operating weight, 182.8 in dig depth, 44 gpm pump flow, and 2.7 gal/hr planning fuel burn. The Cat 320 is a 20-ton class excavator with 172 hp net power, 49,800 lb operating weight, 22 ft dig depth, 113 gpm main hydraulic flow, and 5.2 gal/hr planning fuel burn.
Side-by-Side Decision Points
| Decision Point | Cat 308 CR | Cat 320 |
|---|---|---|
| Primary fit | Tight access, utilities, residential, compact attachments | Trenching, truck loading, site prep, medium production |
| Net horsepower | 69 hp | 172 hp |
| Operating weight | 20,771 lb maximum configuration reference | 49,800 lb reference |
| Dig depth | 182.8 in long-stick reference | 22.0 ft reference |
| Fuel burn estimate | 2.7 gal/hr Heavy Equipment Hub estimate | 5.2 gal/hr Heavy Equipment Hub estimate |
Quick Buying Recommendation
Choose the Cat 308 CR when the job is won by access, lower transport burden, controlled surface damage, attachment flexibility and smaller crew logistics. Choose the Cat 320 when the job is won by production, reach, deeper trenching, truck loading, larger buckets and hydraulic capacity. If the machine will spend most of its week loading trucks, cutting deeper utilities or swinging large buckets, the 320 usually belongs on the shortlist. If the work is residential, landscaped, tight, scattered or attachment-heavy, the 308 CR may produce more billable days with less mobilization friction.
When the Cat 308 CR Makes More Sense
The 308 CR makes more sense when access, transport, surface damage, small crews, attachment versatility, landscaping, residential utilities, sidewalk work, and tight trenching matter more than raw production. It is easier to place on small jobs and can be paired with attachments that keep a compact crew moving.
308 CR Job Examples
- Residential drainage: tight access, short trench runs, careful grading and low surface damage are often more important than bucket size.
- Landscape demolition: thumb work, trailer moves, driveway access and cleanup speed can favor the smaller machine.
- Utility repair: fast mobilization and compact swing radius can matter more than maximum reach when the excavation is short and controlled.
When the Cat 320 Makes More Sense
The Cat 320 makes more sense when trench depth, reach, truck loading, bucket size, lift stability, hydraulic flow, and daily production outweigh transport cost. A 308 CR can be profitable on tight sites, but it becomes expensive if it spends every day doing work that belongs to a 20-ton excavator.
320 Job Examples
- Commercial site prep: larger cuts, stockpile work and truck loading favor reach, bucket size and swing power.
- Deep utility trenching: depth, reach, trench box handling and bedding workflow may exceed compact excavator economics.
- Daily production loading: the larger excavator may burn more fuel per hour but lower cost per yard if trucks and material are matched.
Buying Checks That Matter More Than Size Class
Compare access width, haul setup, dig depth, utility depth, lifting needs, bucket size, attachment requirements, track condition, hydraulic temperature, dealer support, oil samples, and job duration. The right machine is the one that lowers cost per completed job, not the one with the lowest hourly fuel burn.
Transport, Crew and Attachment Math
Before choosing, build the full job setup. Include trailer rating, truck rating, permit needs, bucket transport, extra attachments, operator skill, spotter needs, ground protection, restoration cost and number of moves per week. A 308 CR with the right coupler and thumb may finish scattered small jobs faster because it is easier to move. A 320 may win when one mobilization supports several days of digging, loading or lifting.
Red Flags When Comparing Used Machines
For a used 308 CR, look hard at track wear, blade drift, auxiliary plumbing, compact-radius body damage and attachment abuse. For a used 320, focus on undercarriage measurements, final drives, swing play, boom and stick cracks, bucket linkage, hydraulic heat history and oil samples. The smaller machine can hide expensive attachment damage; the larger machine can hide expensive track and hydraulic repairs.
Source and Verification Notes
Cat 308 CR and Cat 320 values are based on Caterpillar public specifications plus Heavy Equipment Hub equipment profiles. Confirm exact stick, counterweight, blade, bucket, tracks, auxiliary hydraulics, emissions package, and transport weight before buying, renting, hauling, or bidding.
