Maxon GPT, GPT-25, GPT-3, GPT-4, GPT-5 Installation Manual

M-99-49
REV. K
OCTOBER 2005

© MAXON Lift Corp. 2005

TABLE OF CONTENTS

WARNINGS ......................................................................................................................... 3

ST ANDARD LIFTGA TE COMPONENTS .............................................................................. 4

GPT-SERIES INST ALLA TION P ARTS BAGS........................................................................ 5

STEP 1 - PREPARE VEHICLE............................................................................................. 6

STEP 2 - WELD EXTENSION PLA TE TO VEHICLE............................................................. 8

STEP 3 - WELD LIFTGA TE T O VEHICLE .......................................................................... 10

STEP 4 - RUN POWER CABLE ......................................................................................... 14

STEP 5 - CONNECT POWER CABLE ............................................................................... 15

STEP 6 - INST ALL CONTROL SWITCH .............................................................................. 16

STEP 7 - CONNECT POWER CABLE T O BA TTERY......................................................... 19

STEP 8 - REMOVE LOCKING ANGLES & WELDS ........................................................... 20

STEP 9 - WELD PLA TFORM OPENER TO LIFTGA TE....................................................... 21

STEP 10 - FINISH WELDING LIFTGA TE TO VEHICLE....................................................... 24

STEP 11 - INSTALL & ADJUST SADDLES ........................................................................ 25

STEP 12 - CHECK HYDRAULIC FLUID ............................................................................. 26

STEP 13 - WELD HOOK AND EYE TO LIFTGA TE ............................................................. 27

STEP 14 - WELD DOCK BUMPERS TO LIFTGATE........................................................... 28

STEP 15 - BOL T RUBBER BUMPERS TO LIFTGA TE........................................................ 29

STEP 16 - PLACE DECALS .............................................................................................. 30

STEP 17 - VEHICLE T AILLIGHT POSITIONING .................................................................. 32

HYDRAULIC SYSTEM SCHEMATIC ................................................................................ 33

ELECTRICAL SYSTEM SCHEMATIC .............................................................................. 34

OPTIONS ........................................................................................................................... 35

OPTIONAL LIFTGA TE COMPONENTS............................................................................... 35

RECOMMENDED LIFTGA TE POWER CONFIGURA TION ................................................. 36

Comply with the following WARNINGS while installing Liftgates. See Operation Manual
M-97-16 for operating safety requirements.

!

WARNINGS

• Read and understand the instructions in this Installation Manual before installing Liftgate.

• Before operating the Liftgate, read and understand the operating instructions in Operation Manual
M-97-16.

• Comply with all WARNING and instruction decals attached to the Liftgate.

• Keep decals clean and legible. If decals are defaced or missing, replace them. Free replacement
decals are available from Maxon Customer Service.

• Consider the safety and location of bystanders and location of nearby objects when operating the

Liftgate. St and to one side of the platform while operating the Lif tgate

• Do not allow untrained persons to operate the Liftgate.

• Do not stand under, or allow obstructions under the platform when lowering the Liftgate. Be sure
your feet are clear of the Liftgate.

• Keep fingers, hands, arms, legs, and feet clear of moving Liftgate parts (and platform
edges) when operating the Liftgate.

• Correctly stow platform when not in use. Extended platforms could create a hazard for
people and vehicles passing by.

• Make sure vehicle battery power is disconnected while installing Liftgate. Connect vehicle

battery power to the Liftgate only when installation is complete or as required in the installation
instructions.

• Wear appropriate safety equipment such as protective eyeglasses, faceshield and clothing while
performing maintenance on the Liftgate and handling the battery. Debris from drilling and contact
with battery acid may injure unprotected eyes and skin.

• Be careful working by an automotive type battery . Make sure the work area is well ventilated and
there are no flames or sparks near the battery. Never lay objects on the battery that can short the
terminals together. If battery acid get s in your eyes, immediately seek first aid. If acid gets on your
skin, immediately wash it off with soap and water .

• If an emergency situation arises (vehicle or Liftgate) while operating the Liftgate, release the control
Toggle Switch and the Liftgate will stop.

• A correctly installed Liftgate operates smoothly and reasonably quiet. The only noticeable noise
during operation comes from the pump unit while the platform is raised and lowered. Listen for
scraping, grating and binding noises and correct the problem before continuing to operate Liftgate.

• If it is necessary to stand on the platform while operating the Liftgate, keep your feet and any
objects clear of the inboard edge of the platform. Your feet or objects on the plat form could be
trapped between the platform and the Liftgate extension plate.

• Never perform unauthorized modifications on the Liftgate. Modifications may result in early failure of
the Liftgate and may create hazards for Liftgate operators and maintainers.

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

3

STANDARD LIFTGATE COMPONENTS

!

CAUTION

Prevent injuries and equipment damage. Before cutting the shipping straps from
the Liftgate, put Liftgate on level ground that will support at least 1500 pounds. Be
careful lifting and moving components (such as Extension Plate) after shipping
straps are removed.

NOTE: Make sure you have all components and parts before you start installing Liftgate.

Compare parts in the Part Box and each Kit Box with packing list enclosed in each
box. If parts and components are missingor incorrect call:

Maxon Customer Service

Call [phone] or

Send e-mail to [e-mail]

DOCK BUMPER

BRACES

P ARTS BAGS

(SEE TABLE 5-1)

OPENER ASSEMBL Y

ANGLES

PUMP BOX

(SEE T ABLE 5-1)

MAIN

ASSEMBL Y

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

EXTENSION

PLATE

TYPICAL LIFTGATE PACKAGED FOR SHIPMENT

FIG. 4-1

4

GPT-SERIES INSTALLATION PARTS BAGS

STNETNOCXOBSTRAP.YTQREBMUNTRAP

.1"8/1X"1X"2/1-2,TALF2999102
.2REPMUBKCODREBBUR,TIK1014302
.3)AG2#(GULREPPOC1877622

F1224462

.4.GL'83,PMA002,ELBACREWOPDESU
.5"2/1-1X"4/3,DAPDEGROFPORD,EYE1839622
.6.GL"2/1-1X.D.I"8/5,GNIBUTKNIRHSTAEH140-613352
.7YSSAKOOH1007722
.8Y
.9"4/1X"4/3-1X"2/1-3,MIHS2137462

.01"61/1X"1X"2/1-2,MIHS2237462
.11"8/3X"4X"5,TALF2592922
.21TIKSLAUNAM&LACED1-

RAW.D187-87-M

SLACED.F-

.31MOOLREBBUR01#,PMALC2186108
.41"1X42-01WERCSGNIPPAT-FLES45-750009
.51"8/3-1X"2/1,PILCEMARF7970050

SSAHCTIWSDEDLOM110-159462

LAUNAMNOITAREPO.A161-79-M

LAUNAMNOITALLATSNI.B194-99-M

LAUNAMECNANETNIAM.C151-79-M

DRACYTNAR

MROFYEVRUSREMOTSUC.E140-49-M

SEGAPLACEDOTREFER

.LAUNAMSIHTNI

.61ELIFORPWOL,ELDDAS210-948562
.7131-"2/1,DE
.818EDARG,GL"4/1-2,31-"2/1,EMARF,TLOBXEH43-420109

GNALF,TUNKCOL4320109

TABLE 5-1

5

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

STEP 1 - PREPARE VEHICLE

NOTE: BODY Maximum and Minimum Operating Bed Height:

For GPT-25, GPT-3, GPT-4, & GPT -5 With St andard Plat form -

Maximum height is 55” (Unloaded). Minimum height is 46” (Loaded).

On Vehicle Bodies equipped with swing open doors, the Extension Plate
and Vehicle Body must be modified to inst all this Liftgate.

NOTE: Make sure vehicle is parked on level ground while preparing V ehicle and installing

Liftgate.

1. Check for correct clearances (FIG. 6-1 and FIG. 6-2) on vehicle to prevent interference

between vehicle and Liftgate.

APPROX. 20”

(REF . ONL Y)

14”

55” MAX. BED HEIGHT
46” MIN. BED HEIGHT

55” MAX. BED HEIGHT
46” MIN. BED HEIGHT

10”-19”

REF .

GPT-25 & GPT-3 CLEARANCES

FIG. 6-1

APPROX. 24”

(REF . ONL Y)

14”

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

GPT-4 & GPT-5 CLEARANCES

FIG. 6-2

6

12”-21”

REF.

STEP 1 PREPARE VEHICLE - Continued

CAUTION

T o prevent Aluminum Plat form from being damaged, make sure T ruck Frame is cut
correctly as shown in the illustration below. If the Frame is cut incorrectly, Platform
may hit the Truck Frame while stowing Lif tgate.

NOTE: If installing Liftgate on a trailer , skip frame cutting instructions in Item 2.

2. Fit Liftgate to a truck body by cutting the truck frame members as shown in FIG. 7-1.

TOP OF TRUCK

22-1/2”

4-1/2”

12”

BODY FLOOR

20”

TRUCK
FRAME

2-11/16”

CUTS FOR GPT-25, GPT-3, GPT-4 & GPT -5

FIG. 7-1

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

7

STEP 2 - WELD EXTENSION PLATE TO VEHICLE

1. Center the Extension Plate on vehicle body . Before welding Extension Plate to vehicle

body , make sure top surface of Extension Plate is flush with floor of vehicle body . Weld the
Extension Plate to vehicle body sill as shown in FIG. 8-1 and FIG. 8-2.

4” LG.

4” WELDS SHOWN

1/4”

2” LG . CENTERED

BETWEEN

4” LG . LOCA TED ABOVE EACH OF
3 RECT ANGULAR TUBES (TUBES
SHOWN SHADED IN FIG . 3)

(P ART OF VEHICLE BODY)

1/4”

4” LG.

1/4”

1/4”

EXTENSION PLATE WELDS - VIEWED FROM ABOVE

FIG. 8-1

SILL

2 PLACES, MAKE 1”

2” LG , 12 PLACES

EQUAL SP ACING

(TYP.)

1/4”

1/4”

1” GAP

GAP WHERE SHOWN

(P ART OF

VEHICLE BODY)

1/4”

1” GAP

SILL

5 PLACES, MAKE 1”
GAP WHERE SHOWN

EXTENSION PLATE WELDS - VIEWED FROM UNDERNEATH

FIG. 8-2

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

1” GAP

8

STEP 2 - WELD EXTENSION PLATE TO VEHICLE -

Continued

2. Place 2 temporary Support Straps (5” x 4” x 3/8”

flats from Parts Box) on the Extension Plate as
shown in FIG . 9-1A. Also, put 2 temporary
spacers (2” x 1” x 1/8” flats from Parts Box)
between Platform and Extension Plate as shown
in FIG . 9-1B. (Sp acers keep 1/8” between
Platform and Extension Plate while welding
liftgate to vehicle frame.) Weld the S traps and
Spacers to Extension Plate (FIG. 9-1B).

1” (APPROX. - TYP.
STRAP OVERHANG)

1/8” SP ACER

EXTENSION

PLATE

1/4” LG . TACK, SUPPORT

1/4”

4”

17-1/2”

STRAP TO EXTENSION
PLA TE (1 WELD ONL Y),
SP ACER & SUPPORT
STRAP TO EXTENSION
PLA TE (1 WELD ONL Y)

1/2” (APPROX.-

TYP . SP ACER

OVERHANG)

STRAP & SPACER WELDS

(TYPICAL - BOTH ENDS OF

EXTENSION PLATE)

FIG. 9-1B

SUPPORT

STRAPS

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

FIG. 9-1A

9

STEP 3 - WELD LIFTGATE TO VEHICLE

1. Remove Split Looms from Mounting Plates

(FIGS. 10-1A & 10-1B). (S plit Looms will be

reinstalled later after final welding).

MOUNTING

PLA TE

SPLIT LOOMS

MOUNTING PLA TES

FIG. 10-1B

RH SIDE VIEW OF LIFTGATE

FIG. 10-1A

2. Unfold the Platform and Flipover (FIG. 10-2).

LOCKING ANGLES

PLA TFORM

(UNFOLDED)

(REF)

MOUNTING

PLATES

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

FLIPOVER

(UNFOLDED)

PLATFORM & FLIPOVER UNFOLDED

FIG. 10-2

10

STEP 3 - WELD LIFTGATE TO VEHICLE - Continued

!

CAUTION

T o prevent damage to Aluminum Flip Over, NEVER hoist the Liftgate by the
Flipover as shown in the NO illustration. Hoist the Liftgate by the Platform only as
shown in the YES illustration.

3. Make sure Hoist will not

be set up the incorrect
way (FIG. 1 1-2). Place a
“C”-Clamp on each side
of Platform as shown in
FIG. 11-1. (Clamps
prevent Hoist Chain
from slipping off Plat­form.) Place chain all
around Platform

(FIG. 11-1).

HOIST CHAIN

FLIPOVER

PLA TFORM

FLOOR JACK

VEHICLE FLOOR

(HORIZONT AL)

PINS
(LINED UP­VERTICAL)

MOUNTING

PLATE

YES

4. Hoist the Liftgate. Then place

floor jack under Main Frame
(FIG. 11-1). Jack the Liftgate
in position. Make sure V ehicle
Floor is horizontal and Pins are
lined up (FIG. 11-1).

FLIPOVER

MAIN FRAME

CCORRECT WAY TO HOIST LIFTGATE

FIG. 11-1

HOIST CHAIN

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

NO

INCORRECT WAY TO HOIST LIFTGATE

FIG. 11-2

11

STEP 3 - WELD LIFTGATE TO VEHICLE - Continued

!

WARNING

Liftgate is shipped from factory with Mounting Plates that are only Tack Welded to
Main Frame. Weld as shown in illustration before operating Liftgate.

CAUTION

Prevent damaged hydraulic hoses. If welding next to hydraulic hoses, use
a protective cover such as a welding blanket to cover the hoses.

5. Check if both Mounting

Plates line up with the
vehicle frame. If the
Mounting Plates do not
line up, remove the tack
welds from one Mounting
Plate (FIG. 12-1). Make

ORIGINAL T ACK WELDS
(REMOVE TO REPOSITION
MOUNTING PLA TE)

sure Liftgate stays cen­tered on vehicle. Reposi­tion the Mounting Plate
against vehicle frame.
T ack weld as shown in
FIG. 12-1. Repeat for
second Mounting Plate
(reposition and tack
weld).

NOTE: Weld both Mounting Plates to
vehicle frame before welding Mounting
Plates to Main Frame.

T ACK

(TYPICAL - RH & LH

MOUNTING PLA TES)

MAIN FRAME
(CUT-A WA Y VIEW)

REPOSITIONING MOUNTING PLA TE

VEHICLE FRAME CUTOUT

(TYPICAL TRUCK FRAME SHOWN)

5/16”

MOUNTING
PLATE

(RH SIDE SHOWN)

FIG. 12-1

VEHICLE FRAME CUTOUT

(TYPICAL TRUCK FRAME SHOWN)

6. Clamp both Mounting

Plates to vehicle frame.
Before welding, make sure
cutout in vehicle frame
does not block 2 slotted
holes in Mounting Plate
(FIG. 12-2). Weld the
Mounting Plates to
vehicle frame as shown in
FIG. 12-2. Next, weld both
Mounting Plates to Main
Frame (FIG. 12-2).
Remove clamps.

2” LG. 4 PLACES

(TYPICAL - RH & LH

MOUNTING PLA TES)

WELD TO VEHICLE FRAME AND MAIN FRAME

12

5/16”

11921 Slauson Ave. Santa Fe Springs, CA. 90670 [phone] FAX [phone]

MOUNTING
PLATE

MAIN FRAME
(CUT-A WAY VIEW)

5/16”

(RH SIDE SHOWN)

FIG. 12-2