Compare Mowers
List prices are the manufacturer’s published figures, re-checked daily; they exclude tax, freight and dealer setup.
A side-by-side reference of each model's stated specifications. MowerFacts doesn’t give opinions: where a published, spec-derived rule can separate machines we mark a Data Pick and show the rule; here, read the values and decide what fits your needs.
Best suited for
What each model is built for, from its duty class and key specs. This is a neutral reference — MowerFacts does not rank one model above another.
- Cub Cadet PRO X 660 EFI — commercial: daily paid use and high acreage; 60-inch deck; gas powered
- Spartan Spartan RT-HD — commercial: daily paid use and high acreage; 61-inch deck; gas powered
What’s different? The 5 differences that matter most, from the published figures.
- PRO X 660 EFI uses a Kawasaki® engine; Spartan RT-HD uses a Vanguard engine. The engine maker builds the engine; the mower maker chooses the model, rating and fit, so the badge alone does not settle output or longevity.
- PRO X 660 EFI has a 10 ga shell w/ 7 ga top & bottom reinforcement deck; Spartan RT-HD has a 6" Deep, Reinforced 7 Gauge Full-Floating Deck deck.
- PRO X 660 EFI holds 7.5 gal (28.4 L) of fuel; Spartan RT-HD holds 9.5 gal (36 L) of fuel, a 2 gal difference. Tank size bounds how long a machine runs between stops. Consumption varies with engine, load and speed, so hours per tank are not fixed.
- PRO X 660 EFI has a 50.2 ci (822 cc) engine; Spartan RT-HD has a 60.6 ci (993 cc) engine, a 10.4 ci difference. Displacement is the engine's size, not its output. A larger engine is not necessarily a more powerful one.
- PRO X 660 EFI has a published top speed of 10 mph; Spartan RT-HD has a published top speed of 11 mph, a 1 mph difference. Top speed is the maker's maximum in transport. Mowing speed is lower and depends on grass, terrain and the deck.
2 more differences, calculated figures and what isn’t comparable
Other verified differences
- PRO X 660 EFI has a 34.5 hp engine; Spartan RT-HD has a 37 hp engine, a 2.5 hp difference.
- PRO X 660 EFI weighs 1,115 lbs (505.8 kg); Spartan RT-HD weighs 1,143 lbs (518.5 kg), a 28 lbs difference.
Calculated by MowerFacts
- PRO X 660 EFI works out to 4.8 acres/hour; Spartan RT-HD works out to 5.4 acres/hour, a 0.6 acres/hour difference. Calculated by MowerFacts from deck width and the published top speed at 80% efficiency; it is not a manufacturer figure, and real mowing is slower.
Not comparable
- Warranty: not published for PRO X 660 EFI.
- Blades: not published for Spartan RT-HD.
- Transmission: not published for Spartan RT-HD.
- Deck Material: not published for Spartan RT-HD.
- Start Type: not published for Spartan RT-HD.
- Cut height range: not published for PRO X 660 EFI.
Verified means each manufacturer publishes the figure. A bigger number is only a bigger number; nothing here says which machine is better. The full specification table is below.
Which is faster on your property? › Measure your lawn once and MowerFacts times all 2 against it.
| Spec | PRO X 660 EFI Cub Cadet · Commercial |
Spartan RT-HD Spartan · Commercial |
|---|---|---|
| List price | $12,799 | $12,899 |
| Engine | ||
| Power Source | gas | gas |
| Engine Make | Kawasaki® | Vanguard |
| Displacement | 50.2 ci (822 cc) | 60.6 ci (993 cc) |
| Engine Power | 34.5 hp | 37 hp |
| Cylinders | 2 | — |
| Engine Model | FX Series EFI | — |
| Start Type | Ignition Key | — |
| Deck | ||
| Cutting Width | 60 in (1524 mm) | 61 in (1549 mm) |
| Blades | 3 | — |
| Deck Material | 10-gauge steel | — |
| Deck Construction | 10 ga shell w/ 7 ga top & bottom reinforcement | 6" Deep, Reinforced 7 Gauge Full-Floating Deck |
| Deck Gauge | 10 | — |
| Min Cut Height | — | 1.5 in (38 mm) |
| Max Cut Height | — | 4.8 in (121 mm) |
| Drive | ||
| Transmission | 12cc Hydro-Gear® pumps / 240cc Parker® wheel motors | — |
| Ground Speed | 10 mph | 11 mph |
| Drive Tire Size | — | 24x12-12 Radials |
| Reverse Speed | 5 mph | — |
| Dimensions | ||
| Weight | 1115 lbs (505.8 kg) | 1143 lbs (518.5 kg) |
| Fuel Capacity | 7.5 gal (28.4 L) | 9.5 gal (36 L) |
| Length | — | 84 in (2134 mm) |
| Height | — | 75 in (1905 mm) |
| Commercial / Pro | ||
| Frame Construction | — | 1.5" by 3" Powder Coated Fusion-Bonded Solid Steel Bridge Frame |
| Seat Type | — | Full Suspension Seat with Adjustable TecsPak Elastomer supports and 360 degree Floating Seat Platform |
| General | ||
| Warranty | — | 3 yr |
Where these models differ, explained
PRO X 660 EFI: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — cubcadet.com.
Spartan RT-HD: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — joinspartannation.com.
Independent reference database. Specs compiled from manufacturer sources and normalized for comparison; verify with the manufacturer or dealer before purchase.