Westinghouse WPX3600
#6 in GasFull review
For homeowners who want a longer lasting triplex pump and longer hose without paying Honda engine prices.
Amazon $529$529
The Westinghouse WPX3600 is the better pressure washer overall, rated 3.8 to 3.4. The Westinghouse WPX3600 leads on value. The Simpson Aluminum 4200 PSI wins on cleaning power. The Westinghouse WPX3600 costs $868 less ($529 vs $1,397).
Simpson Aluminum 4200 PSI
#9 in GasFull review
For pressure washing businesses that want a CAT pump and a rustproof frame at full 4 GPM flow. The steel frame PS4240 does the same work for less.
Amazon $1,397$1,397
Prices were last checked October 31, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Westinghouse WPX3600 for value ($54.42 per 1,000 cleaning units ($529, 9,720) vs $83.15 per 1,000 cleaning units ($1,397, 16,800)).
- Choose the Simpson Aluminum 4200 PSI for cleaning power (16,800 cleaning units (4,200 PSI x 4 GPM) vs 9,720 cleaning units (3,600 PSI x 2.7 GPM)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every gas pressure washer; a clear win is highlighted. How we rank explains each one.
| Factor weight | Westinghouse WPX3600 | Simpson Aluminum 4200 PSI |
|---|---|---|
| Overall rating | 3.8/5 | 3.4/5 |
| Value 35% | 53 $54.42 per 1,000 cleaning units ($529, 9,720) | 8 $83.15 per 1,000 cleaning units ($1,397, 16,800) |
| Cleaning power 30% | 79 9,720 cleaning units (3,600 PSI x 2.7 GPM) | 100 16,800 cleaning units (4,200 PSI x 4 GPM) |
| Hose 10% | 100 35 ft hose | 100 50 ft hose |
| Warranty 25% | 50 3-year warranty | 50 3-year warranty |
Specifications
| Westinghouse WPX3600 | Simpson Aluminum 4200 PSI | |
|---|---|---|
| Cleaning | ||
| Pressure | 3,600 PSI | 4,200 PSI |
| Flow | 2.7 GPM | 4 GPM |
| Cleaning units | 9,720 | 16,800 |
| Nozzles included | 5 | 5 |
| Detergent | Onboard tank | - |
| Power | ||
| Power | Gas | Gas |
| Engine or motor | 212 cc (Westinghouse OHV) | 389 cc (Honda GX390) |
| Pump | Triplex plunger | Triplex plunger |
| CARB compliant | No | No |
| Build | ||
| Hose | 35 ft | 50 ft |
| Weight | 79 lb | 133 lb |
| Warranty | 3 years | 3 years |