210 Inverness Center Parkway
Birmingham, AL 35242

Telephone: 205-991-7733
Facsimile: 205-991-9993
www.altec.com

This notice applies to your vehicle. See SIL for specific unit identification.
May 28, 2020
Dear Altec Owner,
Altec Industries, Inc. has developed a product improvement which relates to certain AT37-G and AT40-G
aerial device units built from November 2017 to Ocober 2018.
Refer to SIL 749 for items covered under the warranty policy. Altec will supply necessary parts to correct
this condition.
In order to determine if your unit is affected by SIL 749, compare the serial number of your unit with the list of
affected units as described on the SIL. The product improvement can be performed by the customer or you may
contact Altec at 1-877-GO-ALTEC (1-877-462-5832) for further assistance.
At any time, you may contact Altec at 1-877 GO ALTEC (1-877-462-5832) with your unit’s serial number to
determine if there are any other outstanding notices.
If you have sold or retired the unit please call Altec at 1-877-GO-ALTEC (1-877-462-5832) so the records may
be changed.
We regret this inconvenience; however we are taking this action in the interest of your safety and continued
satisfaction with Altec products.
Thank you for your immediate attention on this important matter.

Altec Industries, Inc.
Northern Operations
Indianapolis, IN

SIL 749

Service Information Letter
May 28, 2020
Units Affected: Certain AT37-G and AT40-G aerial devices built from November 2017 to October 2018 (see attached list)

Torsion Bar Inspection on 60" CA Chassis
Altec is committed to providing our customers safe and reliable products from initial delivery
throughout the useful life of the machine.
Altec has discovered that torsion bar mounting brackets and rear shear plates used to mount the
torsion bar assembly can cause interference issues as the torsion bar rotates during road travel.
Altec requires the torsion bar assembly to be inspected and repaired as described in the Inspection and Repair Procedure beginning on page 2 of this SIL. Use the Decision Chart on page 4
to assist in determining the required actions and whether Altec must perform certain repairs. If
the inspection indicates damage to certain torsion bar components, one of the kits shown below
must be installed as specified.
• Torsion Bar Repair Kit, part number 990858321
• Torsion Bar Replacement Kit, part number 991080382 (requires Altec to install)
The inspection and any repairs must be completed no later than the next regular maintenance
interval or 60 days after the receipt of this SIL, whichever comes first.
This inspection and the installation of the torsion bar repair kit are covered under the Altec Warranty Policy, and can be performed by Altec, the customer, or the customer’s warranty provider.
Altec will perform this work for free at an Altec facility. If the customer or the customer’s warranty provider performs this work, a warranty claim must be submitted to be reimbursed for the
cost of the parts and/or labor. Altec will allow up to $90 for the labor to perform the inspection
and up to $180 for the labor to perform the repair described in this SIL. Up to $90 additional is
allowed for the installation of the torsion bar repair kit.
Altec Use Only
Inspection labor
1.0 hr
Repair labor for SIL
2.0 hr
Repair labor for Kit 990858321 1.0 hr
Repair labor for kit 991080382 10.0 hr
Account #
010.0557.43151.736.000.000
Travel
Not Included
NHTSA code
02
Prime fail P/N
None
Doc ref
074900707, 991080146

Parts Kit
Torsion Bar Repair Kit
Torsion Bar Replacement Kit

Page 1 of 8

Part Number Qty
990858321
1
991080382
1

Warranty
Yes
Yes

SIL 749

The installation of the torsion bar replacement kit is covered under the Altec Warranty Policy,
and must be performed by Altec at an Altec service center.
Call 1-877-GO ALTEC (1-877-462-5832) to order a kit or to schedule the work to be done by
an Altec service technician. The customer is responsible for the travel costs of an Altec Mobile
Service technician if the technician performs the inspection or installation of the repair kit at the
owner’s location.
Inspection and Repair Procedure
Soap and water or other appropriate cleaning solution, a flashlight, and an inspection mirror are
required for the inspection procedure. A cut-off wheel, plasma cutter (optional), grinder, primer
paint, and black finish paint are required for the repair procedure.
If the inspection shows that the shear plates must be modified, an electric welder is required to
complete the repair. If an Altec mobile service technician is completing the inspection, welding
will require the unit to be taken to an Altec facility or a qualified third party. All welds must be
applied by a welder qualified in 3G uphill progression welding using one of the following approved methods:
• FCAW-G - gas shielded flux core wire (E71T-1M/9M)
• FCAW-S - gasless self-shielded flux core wire (E71T-11)
• SMAW - stick electrode (E7018 H4R)
• GMAW - solid core wire (ER70S-6)
Use the Decision Chart on page 4 to assist in determining the required actions and whether Altec
must perform certain repairs. Read and understand all steps of the instructions before beginning
the procedure.
Setup
1. Look into both rear wheel wells, using a flashlight if necessary. If there is dirt or debris on the
torsion bar swing arm plates and/or connecting plates (refer to Figure 1), clean these components with soap and water or other suitable cleaning solution to ensure that any potential
defects will be visible.
Front of Chassis
Swing Arm Plate
Torsion Bar
Mounting Bracket

Upper Cap
Screw and Lock
Nut
Connecting Plates
(one on each side of
swing arm plate)
Lower Cap Screw
and Lock Nut
Figure 1 – Street Side Torsion Bar Assembly
Page 2 of 8

SIL 749

2. Position the unit on a level surface and apply the parking brake. Chock both front wheels.
Turn off the engine and remove the key from the ignition.
3. Raise the rear of the vehicle with a jack(s) to allow removal of the rear wheels on both sides.
Properly support the vehicle with jack stands on both sides.
4. Remove the rear wheels on both sides.
Inspecting Torsion Bar Components
5. Look at the torsion bar assembly in the street side rear wheel, using a flashlight if necessary.
If there is any dirt or debris on the swing arm plate, the connecting plates, or the upper lock
nut and cap screw threads (refer to Figure 1), clean these components with soap and water or
other suitable cleaning solution to ensure that any potential defects will be visible.
6. Using a flashlight and a mirror, inspect both connecting plates, the swing arm plate, and the
upper lock nut and cap screw threads from all available angles. Look for any hairline cracks,
bending, denting, or metal chipping.
7. Repeat steps 5 and 6 for the curb side rear wheel well. Then proceed to step 8.
8. Review the results of the visual inspection.
• If there is no cracking, bending, denting, or metal chipping on any of the components, proceed to
step 11.
• If there is any cracking or bending on either of the swing arm plates, immediately take the unit out
of service. It must not be used until the torsion bar assembly is replaced. Proceed to step 10.
• If there is any cracking, bending, denting, or metal chipping on any of the connecting plates, or any
damage to the lock nuts or cap screw threads, the damaged parts must be replaced. Proceed to
step 9.
Planning for Repairs
9. If replacement of any connecting plates, lock nuts, or cap screws is required, call 1-877-GO
ALTEC (1-877-462-5832) and order the Torsion Bar Repair Kit, part number 990858321.
Schedule the installation of the repair kit. Proceed to step 12.
10. If replacement of the torsion bar assembly is required, this repair must be performed by Altec
at an Altec service center. Call 1-877-GO ALTEC (1-877-462-5832) to schedule the installation of the Torsion Bar Replacement Kit, part number 991080382.
Removing Boom Stow Socket Interference
11. Locate the boom stow socket on the side of the subbase in the street side rear wheel well.
Locate the horizontal plate under the boom stow socket (refer to Figure 2).

Page 3 of 8

SIL 749

Decision Chart

Clean and inspect
torsion bar
components.

Is there
cracking
or bending on swing
arm plate(s)?

YES

Schedule installation
of Torsion Bar
Replacement Kit by
Altec.

Remove the unit from
service.

NO

Is there
cracking,
bending, denting or
chipping on
connecting plate(s) or
top fastener(s)?

YES

Order Torsion Bar
Repair Kit and
schedule installation.

Cut out corner on
boom stow socket
horizontal plate.

NO

Cut off front portion of
shear plates. Weld cut
edge of shear plates.

Inspect rear shear
plates.

NO

Are shear plates
located correctly?

Paint any bare metal
where modifications
were made.

Was a
Torsion Bar
Repair Kit
ordered?

NO

YES

Return unit to service.
Complete installation
when kit is received.

YES

Was a
Torsion Bar
Replacement
Kit ordered?

NO

YES

Page 4 of 8

Return unit to service.
Complete the evaluation
sheet at the end of this
SIL.
Keep unit out of
service until repair is
complete.

SIL 749
Boom Stow
Socket
Unit Subbase
Horizontal Plates

Figure 2 – View of Street Side Wheel Well

12. Using a plasma cutter or cut-off wheel, remove the corner portion of the horizontal plate beyond a distance of 1/8" from the edge of the weld beads, as shown in Figures 3 and 4. Do not
cut into the weld beads. Do not cut into the horizontal plate any farther on the bottom than on
the top if using a cut-off wheel.

Boom
Stow
Socket

Weld Beads

1/8"

1/8"

Remove Corner of
Horizontal Plate
Figure 3 – Horizontal Plate Before Modification

Page 5 of 8

SIL 749

Corner of Horizontal
Plate Removed
Figure 4 – Horizontal Plate after Modification

Removing Shear Plate Interference
13. Locate the shear plate at the rear end of the subbase on each side.
• If the shear plates are installed with the entire upper portion placed ahead of the rear end of the
subbase as shown in Figure 5, modification is required. Proceed to step 14.
• If the shear plates are installed with the upper portion extending about 2" +/- 1" behind the rear end
of the
subbase as shown in Figure 6, no modification is required. Proceed to step 16.
Front of Chassis
2"

Shear
Plate
3"

Subbase
Rear End

Subbase
Rear End

Shear
Plate

Figure 5 – Shear Plates Located Incorrectly

Figure 6 – Shear Plates Located Correctly

14. If the shear plates are located incorrectly, a portion of each shear plate toward the front must
be removed. Using a cut-off wheel, cut each shear plate vertically 2" from the front edge
(refer to Figure 7). Using a grinder, remove the weld along the top and front edges of each
shear plate. Do not cut into the side of the subbase tubing with the cut-off wheel or grinder.
Complete the removal of this portion of the shear plates.

Page 6 of 8

SIL 749
Front of Chassis
2"

Grind Off
Weld Here

Remove This
Part of Shear
Plate

Subbase
Rear End

Cut Shear
Plate Here

Shear
Plate
Figure 8 – Welding Modified Shear Plates

Figure 7 – Modifying Shear Plates

15. Weld the cut front edge of each shear plate to the side of the subbase (refer to Figure 8).
Painting Modified Areas
16. Apply prime paint and black finish paint to cover the bare metal in the areas where modifications were performed.
Completion
17. Reinstall the rear wheels. Tighten the lug nuts to the proper torque from the chassis manual.
18. Raise the rear of the chassis with a jack(s) and remove the jack stands. Lower the chassis to
the ground and remove the jack(s).
19. Determine the final status of the unit based on the inspection results of step 8.
• If the torsion bar swing arm plates are damaged, the unit must remain out of service until the
torsion bar assembly is replaced. Do not complete the Evaluation Sheet at the end of the SIL.
• If the torsion bar swing arm plates are not damaged but any connecting plates, lock nuts, and/or
cap screws are damaged, ensure that the replacement of these components is scheduled. Return the
unit to service. Do not complete the Evaluation Sheet at the end of the SIL.
• If no components in the torsion bar assembly are damaged, return the unit to service. Complete the
Evaluation Sheet at the end of the SIL showing the completion of the inspection and return it to
Altec.

Page 7 of 8

SIL 749

SIL 749 Torsion Bar Evaluation

Complete this form and return to Altec to document inspection completion.
Choose one of these options.
• Online through the customer portal – Altec Connect*
Sign in or Register for an account at www.altec.com/altec-connect/
1. Select Equipment
2. Select Altec Product Notices
3. Select Report a Completed APN
• Scan and Email to [email protected]
• FAX to 1-877-659-9929
*Customer performed warranty can be submitted online for reimbursement
through Altec Connect.

Model

Altec Unit

To login to your existing
Altec Connect account,
scan here with your
smart phone!

Date Completed

Company Name: _______________________________________________

Phone____________________________

Service Company Name:_________________________________________

Phone:___________________________

Company Contact: _________________________________________________________________________________
Company Street Address:_____________________________________________________________________________
City _______________________________________________ State:_________________ ZIP Code:________________
Signature:_____________________________________________________

Submission of this form does not order parts or schedule service from Altec.
If the customer or the customer’s warranty provider performs the repair, a warranty claim must be submitted to be
reimbursed for the cost of the parts and/or labor through Altec Connect.
For more information or to schedule the work to be done by an Altec Service technician, call:
1-877-GO ALTEC (1-877-462-5832)
Make copies of this form for additional units if needed.

Page 8 of 8