Douglas Dynamics SnowEx HDV 77770 User manual

8'6" and 9'6"
HDV™ Snowplow
77770, 77780, 77775, 77785,
77870, 77870‑1, 77870‑3
Installation Instructions
TrynEx International, LLC, 531 Ajax Drive, Madison Heights, MI 48071‑2429 • www.snowexproducts.com
July 15, 2020
Lit. No. 52592, Rev. 04
A DIVISION OF DOUGLAS DYNAMICS, LLC
CAUTION
Read this document before installing the
snowplow.
CAUTION
See your SnowEx® outlet/website for specic
vehicle application recommendations before
installation. The Power Match selection
system has specic vehicle and snowplow
requirements.

Lit. No. 52592, Rev. 04 2 July 15, 2020
SAFETY
SAFETY DEFINITIONS
NOTE: Indicates a situation or action that can lead
to damage to your snowplow and vehicle or other
property. Other useful information can also be
described.
CAUTION
Indicates a potentially hazardous situation
that, if not avoided, may result in minor or
moderate injury. It may also be used to alert
against unsafe practices.
WARNING
Indicates a potentially hazardous situation
that, if not avoided, could result in death or
serious personal injury.
WARNING/CAUTION AND INSTRUCTION
LABELS
Become familiar with and inform users about the
warning/caution and instruction labels on the back of
the blade.
NOTE: If labels are missing or cannot be read, see
your sales outlet.
Attach/Detach Label
Warning and Caution Label

Lit. No. 52592, Rev. 04 3 July 15, 2020
SAFETY
HYDRAULIC SAFETY
• Always inspect hydraulic components and hoses
before using. Replace any damaged or worn parts
immediately.
• If you suspect a hose leak, DO NOT use your
hand to locate it. Use a piece of cardboard or
wood.
FUSES
The SnowEx®electrical and hydraulic systems
contain several automotive‑style fuses. If a problem
should occur and fuse replacement is necessary,
the replacement fuse must be of the same type and
amperage rating as the original. Installing a fuse with
a higher rating can damage the system and could start
a re. Fuse Replacement, including fuse ratings and
locations, is located in the Maintenance section of the
Owner's Manual.
PERSONAL SAFETY
• Remove the ignition key and put the vehicle in
PARK or in gear to prevent others from starting
the vehicle during installation or service.
• Wear only snug-tting clothing while working on
your vehicle or snowplow.
• Do not wear jewelry or a necktie, and secure long
hair.
• Wear safety goggles to protect your eyes from
battery acid, gasoline, dirt, and dust.
• Avoid touching hot surfaces such as the engine,
radiator, hoses, and exhaust pipes.
• Always have a re extinguisher rated BC handy,
for ammable liquids and electrical res.
WARNING
Hydraulic uid under pressure can cause skin
injection injury. If you are injured by hydraulic
uid, get medical attention immediately.
SAFETY PRECAUTIONS
Improper installation and operation could cause
personal injury and/or equipment and property damage.
Read and understand labels and the Owner's Manual
before installing, operating, or making adjustments.
WARNING
Lower the blade when vehicle is parked.
Temperature changes could change
hydraulic pressure, causing the blade to
drop unexpectedly or damaging hydraulic
components. Failure to do this could result in
serious personal injury.
WARNING
Remove blade assembly before placing
vehicle on hoist.
WARNING
The driver shall keep bystanders clear of the
blade when it is being raised, lowered, or angled.
Do not stand between the vehicle and the blade
or within 8 feet of a moving blade. A moving or
falling blade could cause personal injury.
WARNING
Do not exceed GVWR or GAWR including
blade and ballast. The rating label is found on
driver‑side vehicle door cornerpost.
WARNING
To prevent accidental movement of the blade,
always turn the control OFF whenever the
snowplow is not in use. The power indicator
light will turn OFF.
WARNING
Keep hands and feet clear of the blade and
T‑frame when mounting or removing the
snowplow. Moving or falling assemblies could
cause personal injury.
CAUTION
Refer to the current Power Match
selection system for minimum vehicle
recommendations and ballast requirements.

Lit. No. 52592, Rev. 04 4 July 15, 2020
SAFETY
FIRE AND EXPLOSION
Be careful when using gasoline. Do not use gasoline
to clean parts. Store only in approved containers away
from sources of heat or ame.
CELL PHONES
A driver's rst responsibility is the safe operation of
the vehicle. The most important thing you can do
to prevent a crash is to avoid distractions and pay
attention to the road. Wait until it is safe to operate
Mobile Communication Equipment such as cell
phones, text messaging devices, pagers, or two‑way
radios.
VENTILATION
BATTERY SAFETY
NOISE
Airborne noise emission during use is below 70 dB(A)
for the snowplow operator.
VIBRATION
Operating snowplow vibration does not exceed
2.5 m/s2to the hand‑arm or 0.5 m/s2to the whole
body.
TORQUE CHART
1/4-20 10
91
54
1/4-28 12
11
71
5/16-1
81
50 212
5/16-2
41
70 240
3/8-16 269 376
3/8-24 29
74
20
7/16-1442
96
06
7/16-20
9/16-12
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16
7/8-9
7/8-14 47
46
69
64
49
091-8
1-12 70
49
95
1/2-13
1/2-20
11.9
13.7
24.6
27.3
43.6
26.9
53.3
93
148
49.4
69.8
77.9
106.4
120.0
8.4
9.7
17.4
19.2
30.8
35.0
49.4
55.2
75.3
85.0
M6 x 1.00
M12 x 1.75
M8 x 1.25
M14 x 2.00
M10 x 1.50
M27 x 3.00
M22 x 2.50
M30 x 3.50
M24 x 3.00
M20 x 2.5011.1
19.5
38.5
67
107
7.7
613
778
1139
1545
450
428
562
796
1117
M33 x 3.50
M36 x 4.00
2101
2701
1468
1952
325
M16 x 2.00 231167
M18 x 2.50 318222
Recommended Fastener Torque Chart
Size Size
Torque (ft-lb)
Grade
5
Grade
8
Metric Fasteners Class 8.8 and 10.9
These torque values apply to fasteners
except those noted in the instructions.
Torque (ft-lb)
Grade
5
Grade
8
Size Size
Torque (ft-lb)
Class
8.8
Class
10.9
Torque (ft-lb)
Class
8.8
Class
10.9
Inch Fasteners Grade 5 and Grade 8
CAUTION
Batteries normally produce explosive gases,
which can cause personal injury. Therefore,
do not allow ames, sparks, or lit tobacco
to come near the battery. When charging or
working near a battery, always cover your
face and protect your eyes, and also provide
ventilation.
• Batteries contain sulfuric acid, which burns
skin, eyes, and clothing.
• Disconnect the battery before removing or
replacing any electrical components.
CAUTION
Read instructions before assembling.
Fasteners should be nger tight until
instructed to tighten according to torque
chart. Use standard methods and practices
when attaching snowplow, including proper
personal protective safety equipment.
WARNING
Vehicle exhaust contains lethal fumes.
Breathing these fumes, even in low
concentrations, can cause death. Never
operate a vehicle in an enclosed area without
venting exhaust to the outside.
WARNING
Gasoline is highly ammable and gasoline
vapor is explosive. Never smoke while
working on vehicle. Keep all open ames
away from gasoline tank and lines. Wipe up
any spilled gasoline immediately.

Lit. No. 52592, Rev. 04 5 July 15, 2020
INSTALLATION INSTRUCTIONS
UNPACKING AND REMOVING SHIPPING
BRACKETS
1. Set aside the blade guides and parts bags. The
vehicle electrical harnesses and Owner's Manual
packet are in the bag with the headlamp box.
Move the attach/detach lever to unpin the
receivers and set aside.
NOTE: Leave handle in the detach position during
entire assembly process.
2. Remove the lag screws and wood blocks securing
the headlamp channel to the headgear and set the
headlamp channel aside.
3. Remove the packaging hardware securing the
headgear to the T‑frame, except for the clevis pins
and the shipping brackets.
4. Remove the fasteners and blocking securing the
T‑frame to the pallet.
5. While supporting the headgear, remove and retain
the clevis pins and discard the shipping brackets
and hairpin cotters.
Remove and discard
shipping brackets
(both sides).
Remove and retain
clevis pins (both sides).
Remove and discard the shipping brackets and
the two cap screws and locknuts from the lift
cylinder.
Remove and discar
d
shipping brackets
(both sides).
Remove and
discard hairpin cotter.
Remove and retain
5/8" x 4-1/4" clev
is pin.
Remove and
discard
3/8" cap screw
and locknut.
Remove and discard
5/8" cap screw
and locknut.

Lit. No. 52592, Rev. 04 6 July 15, 2020
T‑FRAME HOLE POSITION
IMPORTANT! Before assembling headgear to
T‑frame, measure the vehicle mount height to
conrm whether standard receivers or tall receivers
are required, and which T‑frame and headgear holes
to use for installation. (If the vehicle is not available,
use the Position 2 holes on headgear and T‑frame.
Make adjustments later.)
Before measuring the vehicle mount height, the mount
must be installed on the vehicle, ballast (if required)
must be installed, and the vehicle must be parked on a
level surface.
1. Measure the distance "d" from the ground to the
center of the hole in the vehicle mount. Measure
the distance on both sides of the vehicle and
determine average value for "d".
2. Use the following table to determine the proper
hole positions.
Hole Position
Distance "d" Headgear
Hole Position
T‑Frame
Hole Position
11.5" – 13.0" 2 1
13.0" – 14.5" 2 2
14.5" – 16.5" 1 2
16.5" – 18.5"†1 2
† Tall receivers (85121 & 85122) required in place of standard
receivers.
T‑FRAME TO HEADGEAR
1. Position the T‑frame between the headgear strut
and inner ear, aligning the appropriate T‑frame
and headgear holes selected from the Hole
Position table.
2. On each side, insert 1" x 4‑3/4" clevis pins (from
the shipping bracket) from the outside of the
headgear through the correct T‑frame holes.
Secure the clevis pins with 1" at washers and
1/4" x 1‑1/2" cotter pins found in the parts bag.
3. Fold the headgear forward and pin the lift cylinder
to the T‑frame using a 5/8" x 4‑1/4" clevis pin and
1‑1/2" x 5/32" cotter pin from the parts bag.
INSTALLATION INSTRUCTIONS
1/4" x 1-1/2
"
Cotter Pin
1" x 4-3/4"
Clevis Pin
1" Washer
Select holes
based on
distance "d".
Strut
Inner
Ear
21
21
Headgear
T-Frame
Center of Hole
in Vehicle Mount
d

Lit. No. 52592, Rev. 04 7 July 15, 2020
INSTALLATION INSTRUCTIONS
T‑FRAME TO BLADE ASSEMBLY
1. Remove the blade wings from the crate. Remove
the four shipping straps, then replace the cutting
edge hardware.
2. Align the hinges of each wing. Position the
T‑frame assembly between the blade wings so
that the holes in the T‑frame are aligned with the
holes in wing hinges.
3. Insert the pivot pin from top to bottom through all
hinges as shown.
Pivot Pin
1" x 4-3/4"
Clevis Pin
1" x 4-3/4"
Clevis Pin
1/4" x 1-1/2"
Cotter Pins
4. Move the snowplow into a normal operating
position.
5. Remove the protective packaging from the angle
rams.
6. Align the holes in the rod end of the angle ram
with the corresponding holes on the back of the
blade.
7. Install a 1" x 4‑3/4" clevis pin (from the shipping
bracket) from the top down to attach each rod.
Secure the clevis pins with 1/4" x 1‑1/2" cotter pins
from the parts bag.

Lit. No. 52592, Rev. 04 8 July 15, 2020
INSTALLATION INSTRUCTIONS
8. Install the center snow deector using two
3/8" x 2" cap screws and 3/8" locknuts.
9. Install the blade guides with 5/16" x 1" cap screws
and 5/16" locknuts, as shown.
Blade Guide
5/16" x 1"
Cap Sc
rews
5/16" Locknuts
3/8" x 2"
Cap Screw
Pivot
Pin
3/8"
Locknut
Center Snow Deflector

Lit. No. 52592, Rev. 04 9 July 15, 2020
INSTALLATION INSTRUCTIONS
Halogen HeadlampsLED Headlamps
Headlamp
Swivel
Headlamp
Channel
1/2" Flat
Washers
1/2" Lock
Washers
1/2" Hex Nuts
Slotted
Hole
1/2" Ru
bber
Washer
Lift Frame
HEADLAMPS
Headlamps, hardware, and instructions are found in
the headlamp box.
1. Install the vehicle wiring according to the
instructions provided.
2. Set the headlamp channel on the headgear, label
to the front, with the holes aligned.
3. With the correct headlamp on the correct side, set
each headlamp and swivel into place as shown.
4. Secure the headlamps with the correct hardware
for the application as shown. Inner and outer posts
require di󰀨erent hardware. On LED headlamps, a
rubber washer must be installed under the slotted
holes. Hand tighten.
5. Connect the headlamp wires to the headlamps.
6. Aim the headlamps according to the Snowplow
Headlamp Beam Aiming Instructions (Lit. No.
27769). For LED headlamps, tighten the fasteners
to 22 ft-lb (30 N·m). For halogen headlamps,
tighten the fasteners to 50 ft‑lb (68 N·m).
7. From inside the headlamp channel, insert the
cable tie anchors into the holes as shown. The
anchor locking tabs should be horizontal.
8. For halogen headlamps only, install a split rubber
grommet on each headlamp wire 3" from the
headlamp. Insert the grommet and wire into the
slot on the rear of the channel.
9. Route the wires under the channel and down the
back of the driver‑side vertical support. Secure the
wires to the anchors and the vertical support with
cable ties.
WARNING
Your vehicle must be equipped with snowplow
headlamps and directional lights.
Grommet
Run harnes
s
underneath
channel.
Cable Tie
Anchors
Cable
Ties

Lit. No. 52592, Rev. 04 10 July 15, 2020
3. Remove the two hose brackets from the parts
bag. Position one bracket over the passenger‑side
angle ram hoses and align it with the hose
bracket mounting hole in the headgear upright.
Install the bracket to the headgear using a
1/4" x 3/4" pan‑head screw and 1/4" locknut,
leaving the fasteners slightly loose. Repeat on the
driver's side.
4. Adjust the position of the hoses so that they will
have slack when the lift ram is fully extended and
will not be stretched on either side of the hose
bracket.
HYDRAULIC UNIT AND HOSE BRACKET
INSTALLATION
The hydraulic unit comes from the factory
pre-assembled, partially lled, and fully tested.
1. Attach the snowplow to the vehicle according to
the instructions on the back of the blade.
2. Remove the cover from the hydraulic unit. Remove
and discard the factory‑installed pipe plug from
the top of the reservoir and install the breather.
WARNING
Keep 8' clear of the blade when it is being
raised, lowered, or angled. Do not stand
between vehicle and blade or directly in front
of the blade. If the blade hits or drops on you,
you could be seriously injured.
Breather
Filler Pl
ug
WARNING
To prevent accidental movement of the blade,
always turn the control OFF whenever the
snowplow is not in use. The power indicator
light will turn OFF.
Hose
Bracke
t
1/4" x 3/4" Pan-Head
Cap Screw
1/4"
Locknut
Mounting
Hole
INSTALLATION INSTRUCTIONS

Lit. No. 52592, Rev. 04 11 July 15, 2020
OPERATIONAL TEST AND FINAL ADJUSTMENTS
7. Turn the control ON and raise and lower the
snowplow several times. With the plow in the
raised position, fully angle the snowplow from right
to left several times. Activate the control FLOAT
function and make sure the blade is lowered
completely to the ground. Turn the control OFF.
8. Remove the ller plug and check the uid
level. The uid level should be 1"–1-1/2" below
the ll hole. If additional uid is needed, add
SnowEx® Rapid Action Hydraulic Fluid rated
to –40°F (–40°C), or other uid conforming to
Military Specication MIL-H-5606 A, such as
Mobil Aero HFA or Shell AeroShell® Fluid 4 until
uid is 1"–1-1/2" below the ll hole.
NOTE: Loosen the breather slowly to relieve any
pressure in the reservoir.
9. Replace and tighten the breather.
5. Adjust the position of the hose brackets so that
the hoses loop out and away from the center of
the T‑frame as shown in the photo below. Tighten
the 1/4" locknut to prevent the hose brackets from
turning.
6. Install the provided hose wrap as shown above
to prevent the hoses from chang and premature
wear.
NOTE: Failure to complete the installation of
the hose brackets and hose wrap may result in
premature wear and damage to the hoses.
AeroShell®is a registered trademark (®) of Shell Oil Company.
CAUTION
Do not mix di󰀨erent types of hydraulic uid.
Some uids are not compatible and may cause
performance problems and product damage.
Hose Wrap

Lit. No. 52592, Rev. 04 12 July 15, 2020
OPERATIONAL TEST AND FINAL ADJUSTMENTS
BLADE DROP SPEED ADJUSTMENT
The quill in the valve manifold adjusts the blade drop
speed.
1. Lower the blade to the ground before making any
adjustment.
2. On the hydraulic unit, remove the cover.
3. Turn the quill IN (clockwise) to decrease drop
speed. Turn the quill OUT (counterclockwise) to
increase drop speed.
4. Stand 8 feet clear of the blade when checking
adjustment.
5. Replace the cover.
WARNING
Keep 8' clear of the blade when it is being
raised, lowered, or angled. Do not stand
between vehicle and blade or directly in front
of the blade. If the blade hits or drops on you,
you could be seriously injured.
Quil
l
FINAL INSPECTION AND ADJUSTMENT
1. Fully angle the blade in both directions in raised
and lowered positions. Adjust hose ttings, wraps,
and clamps so that the hoses do not contact the
vehicle bumper, have no sharp bends, and are
wrapped at contact points with, and do not become
pinched between the headgear and T‑frame.
2. Apply good quality multipurpose grease to the two
hitch pins.
WARNING
Keep 8' clear of the blade when it is being
raised, lowered, or angled. Do not stand
between vehicle and blade or directly in front
of the blade. If the blade hits or drops on you,
you could be seriously injured.
Grease
hitch pins.

Lit. No. 52592, Rev. 04 13 July 15, 2020
OPERATIONAL TEST AND FINAL ADJUSTMENTS
CENTER CUTTING EDGES
The center cutting edge spacer plate is located on the
T‑frame below the pivot pin hinges.
1. With the blade wings in straight position, the center
cutting edges should touch the center cutting edge
spacer plate. If they do not touch the spacer plate,
adjust the center cutting edges as follows.
2. Loosen the four 5/8" x 2" center cutting edge
carriage bolts, but do not remove them.
3. Slide the center cutting edges inward until they
contact the spacer plate.
4. Re‑tighten the center cutting edge carriage bolts
according to the torque chart.
LUBRICATING THE PIVOT PIN HINGE
Using a rubber-tipped seal-o󰀨 coupler tip, apply a
good quality multipurpose grease at the ve grease
points along the center pivot pin hinge.
5/8" x 2"
Carriage
Bolts
Spacer Plate
Center Cutting Edges
Grease
Points

Lit. No. 52592, Rev. 04 14 July 15, 2020
OPERATIONAL TEST AND FINAL ADJUSTMENTS
With the headlamp switch OFF, activate the
vehicle DRLs.
Snowplow lighting harness DISCONNECTED:
• Vehicle DRLs should be ON.
• Snowplow headlamps should be OFF.
Snowplow lighting harness CONNECTED and
vehicle in DRL mode:
• Check snowplow DRL function per the type of
Isolation Module installed.
Refer to the Mechanic's Guide for information on
the Isolation Module DRL functions.
Joystick or Hand‑Held Control
The snowplow plugs do need to be connected to
the vehicle harness connectors. The control power
indicator light should light whenever the control
ON/OFF switch and the ignition (key) switch are
both in the "ON" position.
3. Connect all snowplow and vehicle harnesses.
Raise the snowplow and aim snowplow
headlamps according to the Snowplow Headlamp
Beam Aiming Instructions included with the
headlamps and any state or local regulations.
4. Check the aim of the vehicle headlamps with the
snowplow removed.
5. When the snowplow is removed from the vehicle,
install plug covers on the vehicle battery cable
and lighting harness. Insert the snowplow battery
cable and lighting harness into the cable boot on
the snowplow.
OWNER'S MANUAL PACKET
If the completed snowplow will be delivered
immediately, the Owner's Manual should be reviewed
with and given to the purchaser according to the
snowplow checklist.
If the snowplow is completed prior to delivery to the
purchaser, attach the Owner's Manual packet to the
electrical cable of the cab control for safekeeping.
VEHICLE LIGHTING CHECK
1. Verify the operation of all vehicle front lighting
prior to connecting the snowplow harness.
2. Check the operation of the snowplow lights with
snowplow mounted to vehicle and all harnesses
connected.
Turn signals and parking lamps
Parking lamps ON:
• Both vehicle and snowplow parking lamps
should be ON at the same time.
Driver-side turn signal ON:
• Both vehicle and snowplow driver‑side turn
signal lamps should ash at the same time.
Passenger-side turn signal ON:
• Both vehicle and snowplow passenger‑side
turn signal lamps should ash at the same time.
Headlamps
Move the vehicle headlamp switch to the
"ON" position. Connecting and disconnecting the
snowplow lighting harness plug should switch the
lights between vehicle and snowplow as follows:
Snowplow lighting harness DISCONNECTED:
• Vehicle headlamps should be ON.
• Snowplow headlamps should be OFF.
Snowplow lighting harness CONNECTED:
• Snowplow headlamps should be ON.
• Vehicle headlamps should be OFF.
Dimmer switch should toggle headlamps between
high and low beams. The high beam indicator on
the dash should light when headlamps are placed
in high beam.
Daytime Running Lamps (DRLs)
An operational check of the vehicle and snowplow
DRLs will depend on the vehicle model, vehicle
DRL system, and type of Isolation Module
installed. Due to the variations in the OEM DRL
systems and the di󰀨erent Isolation Module
options available, checking the functionality of the
snowplow DRLs will depend on the type of module
installed on the vehicle.
CAUTION
Plug covers shall be used whenever
snowplow is disconnected. Vehicle battery
cable is 12V unfused source.

Lit. No. 52592, Rev. 04 15 July 15, 2020
OPERATIONAL TEST AND FINAL ADJUSTMENTS

Lit. No. 52592, Rev. 04 16 July 15, 2020
TrynEx International, LLC, reserves the right under its product improvement policy to change construction or design details and furnish
equipment when so altered without reference to illustrations or specications used. TrynEx International or the vehicle manufacturer may
require or recommend optional equipment for snow removal. Do not exceed vehicle ratings with a snowplow. TrynEx International o󰀨ers a
limited warranty for all snowplows and accessories. See separately printed page for this important information. The following are registered (®)
or unregistered (™) trademarks of Douglas Dynamics, LLC: Automatixx®, HDV™, SnowEx®.
Printed in U.S.A.
A DIVISION OF DOUGLAS DYNAMICS, LLC
TrynEx International, LLC
531 Ajax Drive
Madison Heights, MI 48071‑2429
www.snowexproducts.com