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40 HP Gearbox RW-300, Smooth 1-3/8" Input Shaft

Item #87854
The average rating for this product is 5 out of 5 stars
7 reviews
With a rated horsepower capacity of 40, this gearbox will provide an excellent operation to your rotary cutter. It has a smooth input shaft that measures 1-3/8 inches. This rotary gearbox may be used with 4 foot, 5 foot, and 6 foot rotary cutters. Replaces Kodiak KDK03-0012 and other brands.
Product Overview

Gearboxes work to administer a transfer of speed and torque through their internal gear rotation, helping the overall performance of your rotary cutter. This RW-300 gearbox operates at 40 HP. The housing is constructed from durable ductile iron and the smooth input shaft measures 1-3/8 inches. It has a beveled type of gear, with the gear ratio measuring 1:1.47. Designed for use with 4 foot, 5 foot, and 6 foot rotary cutters, this rotary cutter gearbox has 4 bolt holes measuring 5/8 inch on a 6-3/4 inch bolt circle for installment.

Specifications

  • Fits many brands of mowers
  • Gearbox RW-300
  • Horsepower: 40
  • Max RPM 540
  • Turns both clockwise or counterclockwise
  • For 4 ft., 5 ft., and 6 ft. rotary cutters
  • Housing construction: Ductile iron
  • Mounting Base Thickness is 3/8 inch
  • 9 inches tall
  • Distance between mounting holes is 4-3/4 inch
  • Smooth input shaft: 1-3/8 in diameter X 3-7/8 inches long
  • Output shaft 1-1/2 inch diameter X 12 Spline being 4-1/2 inch length
  • Spline length is 2-5/8 inches 
  • Gear ratio: 1:1.47
  • Gear type: Bevel gear
  • Bolt pattern: (4) 5/8 inch diameter holes on a 6-3/4 inch bolt circle
  • Uses 90 Weight Gear Oil (Not included) See item 16323
  • The input shaft snap ring comes with this and is located in the plastic tube attached to the shaft
  • Rotation is CW or CCW with no modifications; It also comes with the castilated nut
  • For castle nut use ASC # 102241 - 1" Castle Nut
  • For output shaft gearbox seal RW300 use # 89757
  • For input shaft gearbox seal RW300 use #89756
  • For blade hub use #89754
  • For replacement outer input shaft snap ring, use #135429
  • Replaces Kodiak KDK03-0012 and other brands.

Check out our selection of Rotary Mower Parts & Gearboxes

Shipping & Returns

Shipping & Return Policy
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Product Review Summary
Based on 7 reviews
The average rating for this product is 5 out of 5 stars
Overall Rating: 5.0/5.0
Customer Reviews
Perfect fit
This shopper rated the product 5 out of 5 stars

Replaced Mahindra 6SD gearbox. This gearbox was easy to install and runs smoothly.

Did you buy this product from Agri Supply?: Yes
Robert from MO
Fits and works great…..
This shopper rated the product 5 out of 5 stars

I used this gearbox to replace the original on my 1995 Woods XT148 rotary mower. Works great for the price, very smooth and quiet.

Did you buy this product from Agri Supply?: Yes
TRF from VT
First one lasted for 15 years, seal finally went out. About to purchase another!
This shopper rated the product 5 out of 5 stars

Purchased one of these gear boxes for my second hand, 6 ft. rotary cutter of unknown origin 15 years ago. Was a perfect fit. I check the oil level at start of every mowing season. Couple of days ago I noticed it was a bit noisier than usual. Checked oil again and none. Hard to say if the bearing wear caused the output shaft seal to die or vice versa . Gear backlash is still good and not a lot of play in output shaft. I plan to rebuild it if the gears still look ok but need to get cutter working now so going to buy another. I only use the cutter on average 50 hours a year but I still consider 15 years of use to be pretty good service considering the beating it takes in the rocky ground I have and it sits out all year.

Ferd from KS
worked great!
This shopper rated the product 5 out of 5 stars

Was concerned about the bolt pattern but everything lined up perfect! 4 bolts and a shear pin and I was back in action!

Kevin from AL
5' King Kutter
This shopper rated the product 5 out of 5 stars

This replacement gearbox worked perfectly on my bush hog.

PirateKevinNC from NC