OPERATION
GR60/72 02/07 Operation Section 4-6
© 2007 Alamo Group Inc.
OPERATION
3.3 Tractor Horsepower
The power required to operate a mower is determined by the tractor PTO horsepower. For most mowing
conditions, the GR60/72 mower requires at tractor with at least 30 and 40 HP, respectively. Operating the
mower with a tractor that does not have adequate power may damage the tractor engine. Exceeding 90 HP
may cause mower damage by overpowering the unit in heavy cutting conditions.
3.4 3-Point Hitch
The tractor 3-point hitch must be rated to lift at least
1370 lbs. if attaching a GR60 and 1578 lbs. if
attaching a GR72 mower.
GR60/72 mowers can attach to tractor’s with either
a CAT I or II hitch. Refer to the tractor operator’s
manual for the category of the tractor used. If the
hitch does not conform to ASAE Cat I or II
dimensions, the mower may not fit or raise properly.
Consult an authorized dealer for possible
modification procedures to mount nonconforming
hitches.
Use the correct hitch pins for the hitch category
being used. For a Cat I hitch, 7/8” lower and 3/4”
upper diameter hitch pins are used and Cat II
hitches require 1-1/8” lower and 1” upper diameter
hitch pins.
CAT I Implement / Hitch Specification CAT II Implement/ Hitch Specification
Width from outside to outside A-frame.... 26-7/8” Width from outside to outside A-frame....32-3/8”
Quick Hitch width inside lug to lug ......... 27-1/8” Quick Hitch width inside lug to lug ..........33-5/8”
Height from bottom hitch pin to top pin... 18” Height from bottom hitch pin to top pin ...19”
Lower pin diameter ................................. 7/8” Lower pin diameter .................................1-1/18”
Upper pin diameter ................................ 3/4” Upper pin diameter .................................1”
Lynch pin diameter ................................. 15/32” Lynch pin diameter..................................15/32”
3.5 Front End Weight
A minimum of 20% total tractor weight must be maintained on the tractor front end at all times. Front end
weight is critical to maintain steering control and to prevent the tractor from rearing up while driving. If the
front end is too light, add weight until a minimum of 20% total weight is reached on the front tires. Front
weights and weight carriers can be purchased through an authorized tractor dealership. OPS-U- 0005