NHTSA ID Number: 10200405
Manufacturer Communication Number: SIL 819
Summary
Certain 2017-2020 Ford
F350/F450/F550 chassis with Timbren springs installed near the chassis front coil springs can loosen over time and could eventually become disconnected. Altec requires the Timbren springs to be inspected no later than the next preventive maintenance interval or 90 days from the receipt of this SIL, whichever comes first.
This inspection and repair are covered under the Altec Warranty Policy and can be performed by Altec, the customer, or the customer’s warranty provider. Altec will perform the work for free at an Altec facility.
4 Affected Products
Vehicle
| MAKE | MODEL | YEAR |
| ALTEC | AERIAL DEVICE | 2017-2020 |
This notice applies to your vehicle. See attached serial number list.
Dear Altec Owner,
Altec Industries, Inc. has developed a product improvement as described in the included Service Information Letter (SIL). According to our records, you own one or more units this applies to.
Refer to the included SIL for the items covered under the Altec warranty policy.
Compare the serial number of your unit to the included list of affected units to verify that your unit is affected. You may also 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) to update the records.
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.
SIL 819
Service Information Letter
August 13, 2021
Units Affected: 2017-2020 Ford
F350/F450/F550 chassis with Timbren springs installed (Verify that your unit serial number is affected by reviewing the attached list in this SIL or by accessing your fleet on connect.altec.com/login)
Timbren Springs Inspection
Altec is committed to providing our customers with safe and reliable products from initial delivery throughout the useful life of the unit.
The affected units were manufactured with Timbren Springs installed near the chassis front coil springs. Altec has discovered that the Timbren springs can loosen over time and may eventually become disconnected.
Altec requires the Timbren springs to be inspected no later than the next preventive maintenance interval or 90 days from the receipt of this SIL, whichever comes first. The Inspection Procedure begins on page 2. Missing Timbren spring(s) must be replaced. Order the replacement part(s) as described in the Inspection Procedure. Loose Timbren springs must be secured using the Repair Procedure for Loose Timbren Springs beginning on page 3.
This inspection and repair are covered under the Altec Warranty Policy and can be performed by Altec, the customer, or the customer’s warranty provider. Altec will perform the work for free at an Altec facility. If the customer or the customer’s warranty provider performs the work, a warranty claim must be submitted to be reimbursed for the cost of the parts and/or labor. Altec will allow up to $22.50 for the labor to perform the inspection, up to $45 for the labor to perform the repair on one side, and up to $67.50 for the labor to perform the repair on both sides.
Call 1-877-GO ALTEC (1-877-462-5832) option 3 to schedule the work to be done by an Altec Mobile Service technician or option 2 to schedule the work to be done at an Altec facility. Customers are responsible for the travel costs of an Altec Mobile Service technician if the technician performs the inspection and/or repair at the owner’s location.
SEOCONTENT-START
Dear Altec Owner,
Altec Industries, Inc. has developed a product improvement as described in the included Service Information Letter (SIL). According to our records, you own one or more units this applies to.
Refer to the included SIL for the items covered under the Altec warranty policy.
Compare the serial number of your unit to the included list of affected units to verify that your unit is affected. You may also 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) to update the records.
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.
210 Inverness Center Parkway Telephone: 205-991-7733
Birmingham, AL 35242 Facsimile: 205-991-9993
www.altec.com
This notice applies to your vehicle. See attached serial number list.
Page 1 of 5
Altec Industries, Inc.
Elizabethtown Operations
Elizabethtown, KY SIL 819
Service Information Letter
August 13, 2021
Units Affected: 2017-2020 Ford
F350/F450/F550 chassis with Timbren springs installed (Verify that your
unit serial number is affected by reviewing the attached list in this SIL or by accessing your fleet on
connect.altec.com/login)
Timbren Springs Inspection
Altec is committed to providing our customers with safe and reliable products from initial delivery
throughout the useful life of the unit.
The affected units were manufactured with Timbren Springs installed near the chassis front coil springs. Altec
has discovered that the Timbren springs can loosen over time and may eventually become disconnected.
Altec requires the Timbren springs to be inspected no later than the next preventive maintenance interval
or 90 days from the receipt of this SIL, whichever comes first. The Inspection Procedure begins on page 2.
Missing Timbren spring(s) must be replaced. Order the replacement part(s) as described in the Inspection
Procedure. Loose Timbren springs must be secured using the Repair Procedure for Loose Timbren Springs
beginning on page 3.
This inspection and repair are covered under the Altec Warranty Policy and can be performed by Altec,
the customer, or the customer’s warranty provider. Altec will perform the work for free at an Altec facility.
If the customer or the customer’s warranty provider performs the work, a warranty claim must be submitted
to be reimbursed for the cost of the parts and/or labor. Altec will allow up to $22.50 for the labor to
perform the inspection, up to $45 for the labor to perform the repair on one side, and up to $67.50 for the
labor to perform the repair on both sides.
Call 1-877-GO ALTEC (1-877-462-5832) option 3 to schedule the work to be done by an Altec Mobile
Service technician or option 2 to schedule the work to be done at an Altec facility. Customers are responsible
for the travel costs of an Altec Mobile Service technician if the technician performs the inspection
and/or repair at the owner’s location.
Altec Use Only
Parts Kit Part No. Qty Warranty
Timbren spring replacement kit 991340249 1 or 2 Yes
Altec Use Only
Inspection labor 0.25 hr
Repair labor 0.5 hr for 1 spring, 0.75 hr for both springs
Account # 010.0557.43151.634.0000.000
Travel Not included
NHTSA code 02
Prime fail P/N N/A
Doc ref 074900772
Page 2 of 5
SIL 819
Inspection Procedure
The purpose of this inspection is to ensure that two front rubber springs are in place and secured tightly
on the chassis. No tools are required for this procedure. Read and understand all steps of the instructions
before beginning the procedure.
1. Position the unit on a level surface. Apply the parking brake and turn off the engine. Remove the key
from the ignition and secure it. Chock the rear wheels. Follow your employer’s vehicle lockout/tagout
procedure.
Part A – Inspect for Missing Timbren Springs
2. Look for a rubber spring located between the chassis frame rail and the axle near the front coil spring
at both the street side and the curb side of the chassis (refer to Figure 1). If a yellow cone-shaped rubber
spring is present on both sides (refer to Figure 2), no further inspection is needed. Proceed to the
Completion Procedure with Two Rubber Springs.
Figure 1 – Under Chassis View
3. If both black Timbren springs are missing (refer to Figure 3), call 1-877-GO ALTEC (1-877-
462-5832) option 1 and order two Timbren Spring Replacement Kits, part number 991340249. Proceed
to the Completion Procedure with Missing Timbren Spring(s)
Rubber
Spring
Location
Yellow Cone
Spring
Figure 2 – Yellow Cone Spring Installation
Timbren
Spring*
Rubber
Spacer
(Only on
Some
Units)
Steel
Spacer*
Spacer
Plate
Figure 3 – Black Timbren Spring Installation
*=Included
in Kit
Page 3 of 5
SIL 819
4. If one black Timbren spring is missing, call 1-877-GO ALTEC (1-877-462-5832) option 1 and
order one Timbren Spring Replacement Kit, part number 991340249.
Part B – Inspect for Timbren Spring Tightness
5. Check each Timbren spring for tightness (no movement) by attempting to rotate it by hand in the
clockwise direction as viewed from below.
• If spring movement is detected, proceed to the Repair Procedure for Loose Timbren Springs.
• If both springs are tight, proceed to the Completion Procedure with Two Rubber Springs.
Repair Procedure for Loose Timbren Springs
Loctite 262 threadlocker, a hydraulic jack with a 6-ton minimum lifting capacity, and jack stand with a
6-ton minimum load rating are required for this procedure. No other tools are needed. Read and understand
all steps of the instructions before beginning the procedure.
1. Position the unit on a level surface. Apply the parking brake and turn off the engine. Remove the key
from the ignition and secure it. Chock the wheels. Follow your employer’s vehicle lockout/tagout
procedure.
2. Place the jack under the chassis frame on the side with a loose Timbren spring. If both Timbren springs
are loose, start on either side.
3. Raise the vehicle with the jack until the axle hangs freely on that side. Properly support the vehicle
with the jack stand.
4. Remove the loose Timbren spring from the threaded fastener by turning it counterclockwise as viewed
from below. Remove the spacer(s) from the threaded fastener and place it (them) on the ground in the
same orientation as removed.
5. Check if the spacer plate is tight against the chassis frame by trying to rotate it by hand. If it moves,
tighten the spacer plate mounting cap screw to secure the plate firmly to the chassis frame.
6 Apply Loctite 262 threadlocker
in a continuous strip from top
to bottom on the threads of the
Timbren spring mounting fastener
below the spacer plate (refer
to Figure 5).
7. Install the spacer(s) and Timbren
spring on the mounting fastener
in the original orientation,
(refer to Figure 6). Tighten it by
hand by turning it clockwise as
viewed from below until it bottoms
out against the spacer and
cannot be rotated any farther. No
tools are required.
Figure 5 – Preparing Timbren
Spring Mounting Fastener
Figure 6 – Installing
Timbren Spring
Timbren Spring
Apply Thread Locking
Adhesive to Full
Length of Threads
Spacer Plate
Page 4 of 5
SIL 819
8. Use the jack to raise the vehicle off the jack stand, remove the jack stand, and lower the vehicle back
to the ground.
9. Repeat steps 2 through 8 if the Timbren spring on the other side is loose.
10. If both Timbren springs are present, proceed to the Completion Procedure with Two Rubber Springs.
11. If one Timbren spring is missing, proceed to the Completion Procedure with Missing Timbren
Spring(s).
Completion Procedure with Two Rubber Springs
1. Put the unit back into service.
2. Complete the Inspection Sheet at the end of the SIL and return it to Altec.
Completion Procedure with Missing Timbren Spring(s)
1. Put the unit back into service.
2. Do not complete the Inspection Sheet at the end of the SIL. A separate reply card will be provided
with the Timbren Spring Replacement Kit to document the completion of the SIL..
Page 5 of 5
SIL 819
SIL 819 Timbren Springs Inspection Sheet
Company Name: _______________________________________________ Phone____________________________
Service Company Name:_ ________________________________________ Phone:___________________________
Company Contact: _ ________________________________________________________________________________
Company Street Address:_____________________________________________________________________________
City ______________________________________________ State:_________________ ZIP Code:_ _______________
Signature:_ ____________________________________________________
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.
To login to your existing
Altec Connect account,
scan here with your
smart phone!
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.
Model Altec Unit Date Inspected
Serial Number
SEOCONTENT-END
1 Associated Document
Manufacturer Communications
MC-10200405-0001.pdf 782.001KB
- FITMENT: The FR250SDJ suspension enhancement system fits 2017-2024 Ford
F250 Super Duty Rear Suspensions - TOWING SAFETY: Say goodbye to difficult handling, rear sag, and dangerous corner sway while towing or hauling. Timbren SES kits feature Aeon rubber springs that progressively adjust to heavier loads, giving you a smoother, safer ride whether you're hauling an RV across the country or a trailer full of hay. Rated for up to 8,600 lbs, you can tow with confidence knowing your ride is stable and controlled.
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- EASY INSTALLATION: Unlike air bag systems, Timbren SES kits require no post-installation maintenance and can be installed in under 30 minutes—right from your driveway! No special tools, no hassle. You’ll be ready to hit the road quickly with enhanced towing capacity and peace of mind.
- INCLUDES: Comes with 2 patented Aeon SES suspension hollow rubber springs, 2 steel mounting brackets, and all necessary hardware
- 【Highly Compatible】Fit for Ford
F-350 Super Duty, Specifically engineered for Ford
F-350 Super Duty trucks from 2017 to 2025, both 2WD and 4WD models, the FR350SDJ ensures a seamless and secure integration. Sold as a pair (left and right), these springs are designed to match the genuine OEM dimensions and specifications, providing a precise fit that you can rely on. Whether you're a DIY enthusiast or a professional technician, installation is straightforward and doesn't require complicated modifications.(Please note: If the included bolt size is not suitable, please send us a message—we’ll ship the correct replacement hardware at no additional cost.) - 【Superior Performance】The FR350SDJ system features closed micro-cellular rubber springs that provide a smooth progressive spring rate and excellent damping capabilities. With a rated capacity of 8600 lbs, these springs can increase your vehicle's load carrying ability while reducing rear-end sag. They work harder as the load increases, eliminating squat, sway, and roll, ensuring a consistently comfortable and smoother ride, whether your vehicle is empty or fully loaded.
- 【Safe and Stable】By stabilizing sway and enhancing load carrying ability, the FR350SDJ greatly improves driving stability and control, especially when taking turns at high speeds and during heavy crosswinds. This makes for a safer and more enjoyable driving experience, whether you're navigating city streets or taking a long road trip.
- 【Easy to Install】The FR350SDJ system requires no air lines, compressors, or special tools for installation, making it a breeze for DIY enthusiasts and professional technicians alike. Once installed, these springs require no maintenance, ensuring worry-free operation for years to come. With a simple installation process that can be completed in under 30 minutes, you'll be ready to hit the road in no time.
- 【Aftermarket Service】If you encounter any issues with your FR350SDJ , whether it's during installation or after years of use, our professional customer service team is here to help. Simply contact us , and we'll respond within 24 hours to assist you with any replacement parts or installation advice you may need.
- Fitment - This suspension helper spring kit fits for Ford
F-150 2WD 4WD 2015-2023 - Easy to Install - These rubber springs are the direct replacements of the bump stop in the original vehicle, no drilling required, no hardware needed, you can install them using basic hand tools
- Easy to Use - This helper spring kit is of no need for air lines or compressor, and it will automatically adjust when riding on uneven road and keep the vehicle level at all times
- Reliable Performance - There are no need to fill air to these hollow rubber springs, which means you don't have to worry about air leaking and the maintenance is super easy
- More Comfort - Up to 6,600 lbs additional support for you vehicle, each rubber spring works independently, providing smooth and stable ride especially when hauling off-center loads
- HEAVY-DUTY LOAD SUPPORT – Designed for Ford
F-250 Super Duty (2017-2025), the Timbren FR250SDJ Rear SES Kit delivers up to 8,600 lbs of load-leveling support without compromising ride quality. - ELIMINATES SAG & SWAY – Aeon progressive rubber springs automatically adjust under load to reduce rear-end sag, body roll, and trailer sway, providing improved safety and handling when towing or hauling.
- MAINTENANCE-FREE DESIGN – Unlike airbags, Timbren SES kits require no airlines, compressors, or servicing. Once installed, it works for the lifetime of your truck.
- EASY DIY INSTALLATION – Bolt-on installation takes less than 30 minutes using basic hand tools. No drilling, welding, or complicated setup required.
- BUILT TO LAST – Features powder-coated steel brackets and industrial-strength Aeon springs, engineered for harsh road conditions. Backed by a lifetime warranty for worry-free use.
- Timbren FRTT350F
- FRTT350F, Rear Timbren Suspension Kit for the Ford
F-250, F-350 - 10 inches x000 lbs. inches
- 2 Year / 200,000 Mile Warranty
- Iron
Last update on 2026-06-19 / Affiliate links / Images from Amazon Product Advertising API
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