Skip Content

Want to pay an invoice? Please call us at 1-800-GRAINGER (1-800-472-4643).


Lawn Mower, 21 In.Wide, 4.5HP, Push

  • Item# 5NUG3
  • Mfr. Model# 911170
  • Catalog Page# N/A
  • UNSPSC# 27112014
Lawn Mower,21 In.Wide,4.5HP,Push close
close x

Using 360° Viewing:

  1. Rotate: Use top-to-bottom, side-to-side by use of mouse arrow.
  2. Zoom In: Double click on image.
  3. Zoom Out/Reset: Put photo at full zoom & then double click.
Megaphone How can we improve our Product Images?

Price $723.00 / each

Activate Now

to save with

Select AdvantageSM

Please sign in or register to access lists

Please sign in or register to access Quote

Jump to:
  • Shipping Weight 100.0 lbs.
Country of Origin USA Country of Origin is subject to change.
Note: Product availability is real-time updated and adjusted continuously. The product will be reserved for you when you complete your order. More

Product Details

This walk-behind mower features a multiposition handlebar designed to reduce hand and wrist fatigue while making bigger jobs more manageable. 0.37-gal. fuel capacity.

View More

Technical Specs

  • Item Walk Behind Mower
  • Drive Type Push
  • Cutting Width 21"
  • HP 4.5
  • Displacement 173cc
  • Discharge Mulch, Side or Bag
  • Cutting Height 1 to 3-1/4"
  • Engine 173cc Kohler XT-8
  • Fuel Tank Capacity 0.37 gal.
  • Handle 4-Position
  • Front Wheel Dia. 7-1/2"
  • Rear Wheel Dia. 10.5"
  • Standards ANSI standard B71.1
  • Includes Mulch Plug, Side Discharge Cover and Bagger
Megaphone How can we improve our Technical Specifications?

Compliance and Restrictions

Replacement Parts

Need help finding replacement parts? Please use the list below or call 1-800-GRAINGER (1-800-472-4643)

Alternate Products

Alternate Products may not be identical in style or function to original selection. Please compare below for more information.

Alternate Search Terms

Customer Reviews

Rated 3.8 out of 5 by 93reviewers.
Rated 3 out of 5 by Commercial User Have bought 4 of these mowers. A good cut, fast speed on the ground, not to heavy.Problem is the bearings in the drive assembly don't last long. Pity as otherwise a great mower.Getting parts in the UK a problem. Approved dealers not much help. May 29, 2014
Rated 5 out of 5 by A+ product my first Ariensused products on golf course years agowish I had bought one sooner! June 17, 2013
Rated 3 out of 5 by Decent Lawn mower for price Started 1st pull from box. Hand vibrt'ns need work. June 14, 2013
Rated 5 out of 5 by Replaces our old Ariens mower Great mower, just like the old 20+ yr old one we had June 13, 2013
Rated 4 out of 5 by This is - overall a great product - Purchased the Kawasaki LM-21-SW a year ago - and I would recommend this mower. But I do have a couple of modification I wish Ariens would consider.If you have hills or any sloping terrain I would not recommend the swivel wheels. The unit wants to move in the direction of the slope. It would be nice if the swivel wheel lock mechanism would lock both wheels. One locked wheel is basically useless. I also need to load this machine onto a pickup and pushing it up a ramp is very tricky because of the swivel wheels.Another issue is the pins that holds the front swivel wheels has fallen out a number of times. I have had to replace both pins (lost them in the grass) because the clasp that hold the pins falls out. I replaced both swivel wheel pins with new ones and replaced the clasp with a coder-pins. Now if I need to adjust my wheel height I have to replace the coder-pin. Makes it harder to adjust the height but now I am not at risk of losing the SW-Pin.Changing the oil is next to imposable without making a mess. The drainage plug is set into the side of the engine disabling the ability to catch the oil when the drainage plug is removed. It would be nice if the unit came with some type of extension tube enabling the owner to change the oil without making a mess. I made an extension tube that I use enabling me to drain the oil out beyond the mower deck. Changing the oil a couple of times got me to think about this modification that should have been part of the design to begin with.Like I said, I would recommend this unit. Over all it’s a great machine. All of the above issues I have been able to work around making it a real nice unit. October 8, 2012
Rated 1 out of 5 by Parts broke easily and carb replaced then finally had to replace motor The very first day I had our mower, I pulled the cord to start it and the handle from the cord spun around and broke the knob to tighten the handle on the right side. Then replacing the air filter the plastic cover is hooke don by plastic tabs that broke off . The carb got stuck and the engine began smoking and would then stop...called..took it to suggested repair shop...first I was told it had to much oil, the 2nd time in the shop they replaced the carb, the 3rd time they said it was due to dirt getting in from air filter....we called kohler again and they said take to another repair shop we did...they replaced the happened again, they said nothing wrong with it...oh and all this time these shops charged me when they said nothing was wrong...finally the shop called kohler and they said to replace the carb one more time...we called and they then agreed to replace the motor....runs for now but the history of these carbs will do it again soon and I will be out of luck...what a waste of money....should have spent the extra for a real name brand. August 2, 2012
Rated 4 out of 5 by Started on first pull! Doing an excellent job so far. Easy assembly and started with first pull. Easy to change from bag to side discharge and to mulching. So far I'm very pleased. July 8, 2012
Rated 5 out of 5 by Great mower, has 6-HP Kawasaki motor & swivel front wheels My last mower was a commercial grade mower with a 5 hp Kawasaki motor and lasted 19 years. So, when I retired it, I wanted another commercial grade mower with a Kawasaki motor. I could not find one anywhere locally, but found an Ariens mower that had everything I needed online at The Ariens Classic LM21SW (21") 6-HP Self-Propelled Lawn Mower w/ Swivel Wheels is powerful, very manuverable around flower beds and simply a pleasure to use. My wife laughed at me when I first used it, because I was smiling from ear to ear and looked liked I was actually having fun cutting the grass. June 22, 2012
  • 2015-09-08T19:48:18.267-05:00
  • bvseo_lps, prod_bvrr, vn_prr_5.6
  • cp-1, bvpage1
  • co_hasreviews, tv_93, tr_93
  • loc_en_US, sid_5NUG3, prod, sort_default
2 3 4next>>

Product Reviews Disclaimer:
Grainger is neither responsible for, nor does it endorse, the content of any product review or statement posted. Any statements posted constitute the statements of the poster and are not the statements of Grainger. The statements posted by Grainger employees with the Grainger employee badge represent the views of such employees and are not the statements of Grainger. Grainger makes no representations as to the appropriateness, accuracy, completeness, correctness, currentness, suitability, or validity of any product review or statements posted, including those posted by employees with the Grainger employee badge, and is not liable for any losses, injuries or damages which may result from any such product review or statements. Use of any linked web site provided in a product review or post is at the user's own risk.