Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
Briggs & Stratton 40586
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Briggs & Stratton 20kW Home Standby Generator (Steel)



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Lift Gate
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Free Shipping & Lift Gate
*This product qualifies for Free Shipping anywhere in the contiguous US. Accessories may ship separately. Items over 100lbs shipped via semi-truck, be sure to select "Lift Gate" to lower the product to the ground curbside. Remote area surcharges may apply, see our full shipping policy for more details.
Ships in 16-20 Weeks
Factory items ship direct from the manufacturer. Shipping times vary.
Shipping Details
  • Free to Lower 48 States
  • Lift Gate Service Available - Free Lift Gate Learn More
*We currently CANNOT ship this product to Alaska, Hawaii or any destination outside of the United States
$77 / Month
With our 82 months 10.99% APR*
82 fixed monthly payments required.
Available Add-Ons
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Lift Gate Service
All products weighing more than 100 lbs. ship via semi-truck. We recommend ordering the Lift Gate Service to safely lower the product to the curb. If you have a loading dock or forklift, you do NOT need a Lift Gate service. If you are a residential customer, you must have at least 2-4 able-bodied people present to unload the product. Learn More
Learn More Installation
Briggs & Stratton 20kW Home Standby Generator (Steel)
Briggs & Stratton 20kW Home Standby Generator (Steel)
Model: 40586
How-To Articles





Standby (Air Cooled)

Run Watts

20,000 Rated Watts


120/240 Single-Phase


LP/Natural Gas


Briggs and Stratton Vanguard
  • B&S 20kW (LP) / 18kW (NG) Air-Cooled Standby Generator
  • Automatically powers your home in seconds after sensing an outage*
  • Runs on Natural Gas (NG) or Liquid Propane (LP)
  • Simple field conversion for easier installations
  • 993cc Commercial-Grade Vanguard® Air-Cooled Engine
  • Full-pressure lubrication system w/ spin-on oil filter
  • Advanced debris management for enhanced durability
  • Briggs & Stratton Alternator - Less Than 5% THD
  • Improved frequency (HZ) regulation for cleaner power
  • Automatic Voltage Regulation (+/-1%)
  • Helps prevent damaging voltage spikes
  • Flexible Placement (Please Verify Local Building Codes)
  • Tested against tough National Fire Protection Agency standards
  • Can be placed as close as 18ā€¯ from structure
  • New Upgraded Control System
  • LCD display w/ multi-line text graphics
  • Low Idle mode for quieter exercise
  • Independent 3-Stage Battery Charger
  • Provides optimized charge for longer battery life
  • Automotive-Grade Galvaneal Steel Enclosure
  • Helps minimize corrosion & protects it from the elements
  • 5 Year Limited Best in Class Warranty
  • Covers parts, labor, and travel for 5-Years
  • Assembled & Engineered In The USA
  • From foreign and domestic parts
  • Requires (Sold Separately)
  • Briggs & Stratton Automatic Transfer Switch* & Battery
California residents see
WARNING: Cancer and Reproductive Harm -
For more information go to:


Product Specs
120/240 Single-Phase
60 Hertz
Auto Voltage Regulation
Rated Watts
20000 Watts
Fuel Type
LP/Natural Gas
NG Power Capacity
18000 Watts
LP Power Capacity
20000 Watts
NG Fuel Consumption @ 50% Load
187 ft³/hr
NG Fuel Consumption @ 100% Load
260 ft³/hr
LP Fuel Consumption @ 50% Load
2.24 gallons/hr
LP Fuel Consumption @ 100% Load
3.65 gallons/hr
Rated Amps
83.3 Amps
Decibel Rating @ 7m Learn More
Decibel Rating @ 7m
Sound levels are measured in decibels (dB). The lower the decibel rating, the less noise the product makes. As an example, a ticking watch is 20 dB while on the other end of the scale, a lawn mower is around 90 dB.
Transfer Switch
Automatic (Not Included)
Not Included (540 CCA)
Circuit Breaker Size
100 Amps
A/C Ton Rating
2 x 5-Tons
Mounting Pad
Steel (Included)
Cooling System
Air Cooled
UL Listed
Grade Type
Engine Brand
Briggs and Stratton Vanguard
Starting System
12v Auto Start
993 CC
Consumer Engine Warranty
5 Years
Engine RPM
3600 RPM
Low Oil Alert/Shutdown
489 Pounds
Made in USA
Consumer Warranty
5 Years
Product Length
50.5 Inches
Product Style
Standby Generator
Product Width
33.8 Inches
Product Height
31 Inches


Briggs & Stratton 40586 Reviews & Ratings

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