News

NOTICE!!!

UREA systems to meet 2010 EPA Regulations for diesel engines

The State of Florida Consortium has awarded a contract to Transit Dynamics of Marco Island Florida, to provide Diesel Exhaust Fluid (DEF) and dispensing equipment. This contract runs until June 2015.
For additional information you can contact Jerol Ayasun at 239-394-6099 ext.26.
Copies of the contract can be found at: http://www.transitdynamics.com/flcontract.html

Document ID: 2368553
#09-06-05-005: Information on Diesel Particulate Filter Regeneration – (Nov 13, 2009)
Note: Isuzu and Caterpillar Diesel Particulate Filter operations are provided as a reference only.
Only authorized Isuzu or Caterpillar Dealers may service or warranty the respective diesel engines
and emissions controls. GM does not provide limited warranty coverage for the 7.8L Isuzu or 7.2L
Caterpillar Diesel or related emissions components.
A dealer or customer may have questions about active or service Diesel Particulate Filter (DPF)
regeneration intervals and manual button press operation. A customer may need clarification of
when regeneration will occur, and which indicator will be displayed on the instrument panel when
the regeneration is active. Please provide a copy of this bulletin to customers that need clarification
on DPF operation.
As an example with the 6.6L Duramax Diesel (LMM), DPF regenerations are based on ECM
calculations of mileage, fuel used, soot mass, and engine run time. The criteria are:
If any one of the criteria listed above is reached (since the last successful regeneration), the ECM
will command an active regeneration. These criteria are approximate and may differ depending on
vehicle location, altitude and engine RPO code.
As another example, with the Isuzu 7.8L Diesel, this process occurs at 290 km (180 mi) intervals
or sooner. Additional information related to the Isuzu 7.8L Diesel DPF operation can be found in a
video that can be downloaded from the following web sites: WWW.ISUZUTRUCKSERVICE.COM,
WWW.ISUZUCV.COM, WWW.ISUZUCV.ORG and WWW.ISUZUDIESELENGINE.COM.
Recommendations/Instructions
Warning: During DPF self cleaning or during extended idling in P (Park), the exhaust system and
exhaust gases are very hot. Things that burn could touch hot exhaust parts under the vehicle and
Subject: Information on Diesel Particulate Filter Regeneration
Models: 2007-2009 Chevrolet Kodiak 4500-8500 Series, T-Series
Medium Duty Tilt Cab
2007-2009 GMC TopKick 4500-8500 Series, T-Series Medium
Duty Tilt Cab
All Equipped with Either Duramax™ Diesel Engine (RPO LMM), Isuzu
Diesel Engine (RPO LF8) or Caterpillar® Diesel Engine (RPO LF6)
Please Refer to GMVIS
• 480 km (300 mi) traveled
• 170L (45 gal) of fuel used
• 44 grams of soot mass
• 14 hours of engine run time
© 2010 General Motors. All rights reserved.

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ignite. You or others could be burned. Do not park, or idle for an extended period of time, near or
over papers, leaves, dry grass, or other things that can burn. Keep the exhaust area clear of
material that could ignite or burn.
The information below is to provide a better understanding of the DPF operation. Additional
information regarding DPF operation can be found in the Owner’s Manual, the Service Manual and
the driver side sun-visor label.

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Chevrolet and GMC Medium Duty trucks have two regeneration telltale indicators on the instrument
panel shown above, and a manual regeneration button (1) located in the switch bank, shown above.
The green telltale means the ECM is commanding an automatic regeneration. The separate yellow
or red telltale informs the customer to operate the vehicle in a manner to complete a regeneration
event. The manual regeneration button can be utilized when the vehicle cannot be driven
immediately. Refer to Manual Regeneration Procedures in the vehicle Owner’s Manual.
The Regeneration Modes Quick Reference Table at the end of this bulletin provides a quick
reference for the operating modes of the DPF system. Additional details are provided below.

When There Are No Indicators On
Warning: During DPF self cleaning, the exhaust system and exhaust gases are very hot. Stay clear
of the tailpipe area and do not park over things that burn. You or others could be burned or the
vehicle could catch fire. Refer to Parking Over Things That Burn in the vehicle Owner’s Manual.
Important: Using the selectable manual DPF regeneration will reduce the engine oil life at a
significantly faster rate than by driving the vehicle to allow automatic regeneration. This will be
reflected in the engine oil life monitor if equipped.

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If there are no DPF indicators on you may be able to clean the DPF by performing the selectable
manual cleaning procedure.
Note: The manual cleaning procedure below is for conditions when there are no DPF indicators on.
If the indicators are yellow or red, follow the manual cleaning procedure under the section titled
When the Yellow or Red Indicator is On.
The selectable manual cleaning procedure may be helpful for customers that need to have the
system operating from the baseline clean point for the DPF. For example, the operator of a truck
used with low speed, low load PTO conditions, or a large amount of idling in city traffic, may wish
to perform the selectable manual regeneration at the start of each day’s operations or during
breaks to gain the maximum time between required manual (or automatic) regeneration events for
the DPF.

Manual Cleaning Procedure
When it is safe to do so, stop the vehicle. Perform DPF selectable manual cleaning in a well
ventilated area. DPF selectable manual cleaning must be performed outdoors, as follows. Once
manual cleaning is started, complete the manual cleaning in a single operation if possible. If
manual cleaning is not completed, as indicated by the green DPF indicator going off, and the yellow
or red indicator light remains on, self cleaning will not be allowed until the vehicle is stopped and
selectable manual cleaning is performed until completed.
1. Check engine oil and engine coolant levels to be sure they are at proper operating levels.
2. To prevent running out of fuel during manual cleaning, make sure there is at least a quarter
of a tank of fuel.
3. Inspect to make sure the area near the exhaust tailpipe and under the exhaust system are
clear of any materials that could catch fire. Keep people away from the area of the exhaust
system and exhaust gases.
4. Fully set the parking brake.
5. Shift the transmission to P (Park) or N (Neutral).
6. Idle the engine. If you used the idling control knob to increase the engine speed, restore it all
the way to the left to reduce the engine speed.
7. If the vehicle has a Power Take Off (PTO), turn the PTO off. Refer to Power Take-Off (PTO) in
the Owner’s Manual.
8. To initiate a selectable regeneration, press and hold the DPF button.
Note: If the yellow or red DPF indicator is not illuminated, pushing and releasing the button
will result in a dinging/chiming tone and nothing else.
9. If the jewel indicator on the button starts flashing, press the button again and the
regeneration process will begin. If the button is not pressed when the jewel lamp is flashing,
no regeneration will begin. If the jewel indicator on the button does not start flashing, a
selectable manual regeneration cannot be performed.
The orange DPF indicator, the green DPF indicator and the jewel indicator on the button will
come on, the exhaust gas control valve operates, engine idle speed automatically increases,
and DPF cleaning begins. Do not leave the vehicle unattended during manual cleaning.
Caution: Once the process has been started it must be completed. If not, the automatic
regeneration will not be performed leading to a yellow light, red light, reduced engine power
and potential DPF damage.
10. When both the green and the yellow DPF indicator lights go off, cleaning is completed.

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Manual cleaning is normally completed in about 30 minutes.
Under certain operating conditions, manual cleaning may not be allowed, even if the soot level in
the DPF requires cleaning. This can occur because of low coolant temperature, low battery voltage,
high exhaust temperature or immediately after starting the vehicle. When manual cleaning is
requested and coolant temperature is low, an engine warm-up cycle is started. The green indicator
light will come on, the exhaust gas control valve operates, and engine RPM increases to help raise
engine coolant temperature. When operating conditions allow, cleaning will begin.
When a Green Regeneration Indicator is On
During self cleaning, the green DPF indicator light will come on. To clean the filter, either drive the
vehicle above 50 km/h (30 mph) to activate self cleaning, or stop the vehicle and perform the
selectable manual cleaning procedure. See Manual Cleaning Procedure below. For self cleaning,
drive until the green DPF indicator light goes off. This will take approximately 20 minutes. Once self
cleaning has started, drive until the green indicator light goes off to complete the cleaning in a
single operation if possible. Please note the following:
When the Yellow or Red Indicator is On
If a yellow or red regeneration indicator is illuminated, the DPF system has calculated that one of
the regeneration criteria for mileage, fuel used, soot mass, or engine run time is above a specific
threshold. At this point, a regeneration needs to be completed as soon as possible. The vehicle can
be driven above 30 mph until the indicators turn off and regeneration is completed, or if the vehicle
cannot be driven immediately, a stationary regeneration can be initiated with the use of the
manual regeneration button. The manual regeneration button will only need to be pressed once
with a yellow or red indicator illuminated. The engine will run at approximately 950 RPM during a
manual button initiated idle regeneration. Both the green and yellow (or red) indicator telltale will
be illuminated during the regeneration.

Manual Cleaning Procedure
The manual regeneration button allows a customer to initiate a regeneration event during an
engine idle condition. A service regeneration can be initiated by the appropriate service and
diagnostics tool and is used with certain SI procedures. Always review the owner’s manual
description for Manual Regeneration Procedures before completing a regeneration.
Warning: During DPF self cleaning, the exhaust system and exhaust gases are very hot. Stay clear
of the tailpipe area and do not park over things that burn. You or others could be burned or the
vehicle could catch fire. Refer to Parking Over Things That Burn in the vehicle Owner’s Manual.
Important: Using the selectable or manual DPF regeneration will reduce the engine oil life at a
• The regeneration may take longer in city type stop and go traffic.
• The green indicator will go off if the vehicle is stopped and/or the transmission is shifted into
Park or Neutral.
• If the transmission is shifted into Park/Neutral or the engine is shut off during a green light
regeneration, the process is not complete. However the self cleaning regeneration will restart
the next time the vehicle reaches proper speed and engine operating temperature. During
self cleaning regeneration, the engine will idle at approximately 800 RPM.
• If a vehicle is stopped while the green regeneration indicator is illuminated, the green DPF
indicator will turn off, however a selectable manual regeneration event may be performed.

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significantly faster rate than by driving the vehicle to allow automatic regeneration. This will be
reflected in the engine oil life monitor if equipped.
If the yellow or red DPF indicator is on, you can clean the DPF by performing a manual cleaning.
When it is safe to do so, stop the vehicle. Perform DPF manual cleaning in a well ventilated area.
DPF Manual cleaning must be performed outdoors, as follows. Once manual cleaning is started,
complete the manual cleaning in a single operation if possible. If manual cleaning is not completed,
as indicated by the green DPF indicator going off, and the yellow or red indicator light remains on,
self cleaning might not be allowed until the vehicle is stopped and manual cleaning is performed
until completed.
1. Check engine oil and engine coolant levels to be sure they are at proper operating levels.
2. To prevent running out of fuel during manual cleaning, make sure there is at least a quarter
of a tank of fuel.
3. Check to make sure the area near the exhaust tailpipe and under the exhaust system are
clear of any materials that could catch fire. Keep people away from the area of the exhaust
system and exhaust gases.
4. Fully set the parking brake.
5. Shift the transmission to P (Park) or N (Neutral).
6. Idle the engine. If you used the idling control knob to increase the engine speed, restore it all
the way to the left to reduce the engine speed.
7. If the vehicle has a Power Take Off (PTO), turn the PTO off. Refer to Power Take-Off (PTO) in
the vehicle Owner’s Manual.
8. Press the DPF switch in the instrument panel switch-bank. Refer to Instrument Panel
Switch-bank in the vehicle Owner’s Manual. The green DPF indicator light comes on, the
exhaust gas control valve operates, engine idle speed automatically increases, and DPF
cleaning begins. Do not leave the vehicle unattended during manual cleaning.
Caution: Once the process has been started it must be completed. If not, the automatic
regeneration will not be performed leading to a yellow light, red light, reduced engine power
and potential DPF damage.
9. When both the green and the yellow or red DPF indicator lights go off, cleaning is completed.
Manual cleaning is normally completed in about 30 minutes.
Under certain operating conditions, manual cleaning may not be allowed, even if the soot level in
the DPF requires cleaning. This can occur because of low coolant temperature, low battery voltage,
high exhaust temperature or immediately after starting the vehicle. When manual cleaning is
requested and coolant temperature is low, an engine warm-up cycle is started. The green indicator
light will come on, the exhaust gas control valve operates, and engine RPM increases to help raise
engine coolant temperature. When operating conditions allow, cleaning will begin.

Regeneration Modes Quick Reference Table
Mode Name Description
• ECM monitors sensor input and determines DPF regeneration is
necessary
• The ECM commands the green DPF lamp “ON”
• Vehicle should be driven normally
• When idling at a stop the exhaust brake may activate and the idle
speed may increase. Important: If the parking brake is set or the

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Automatic
Regeneration
“Park “position is selected, the automatic regeneration will be
canceled.
Urgent
Regeneration
• Yellow or red light comes “ON”
• Driver MUST choose one of the following options to perform this
regeneration. If one of the following options is not completed, Limp
Home Mode may be activated
Running
Option 1
• Drive vehicle above 30 mph
• ECM monitors sensor input and determines if
regeneration is possible
• The ECM commands the green DPF lamp “ON”
• Vehicle should be driven normally
• When idling at a stop the exhaust brake may activate
and the idle speed may increase.
Important: If the parking brake is set or the “Park
“position is selected, the automatic regeneration will
be canceled.
Switched
Option 2
• Set the parking brake, engine running and
transmission in Park or Neutral Position
• Press DPF switch
• Green DPF lamp comes “ON”
• Engine RPM increases and exhaust brake activation for
about 20 minutes
• If this is interrupted must press DPF switch to restart
process
Important: Once Urgent Switched or Selectable Regeneration Modes have been selected,
the Automatic and Urgent Running Modes are no longer available. Automatic and Urgent
running modes will become available after Switched or Selectable DPF regeneration is
completed.
Selectable
Regeneration
Note: For quickest possible regeneration, be sure the vehicle is at
operating temperature before performing selectable regeneration.
• Engine running and in “Park” Position
• Parking brake is applied
• Press and hold the DPF switch until the DPF switch jewel lamp comes
“ON”
• If the jewel lamp goes “Off”, regeneration is not necessary
• If the jewel lamp blinks, it means that regeneration is possible
• Press the DPF switch again to start regeneration
• The orange DPF lamp, green DPF lamp and then the jewel lamp will
turn “ON” indicating that regeneration is taking place. This will take
about 20 minutes
• Engine RPM will increase and the exhaust brake will activate

Caution: The following actions will interrupt the stationary type regeneration. Failure to
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restart and complete the regeneration cycle will result in filter clogging
• Applying the accelerator pedal
• Shifting into gear (with Automatic Transmission)
• Pressing the clutch pedal (Manual Transmission)
• Engine speed increases
• Releasing the parking brake
Limp Home
Mode
Important: This condition should only be diagnosed and repaired by a
factory trained technician.
• MIL and/or Reduced Engine Power Lamp is “ON”, vehicle speed is
reduced
• Technician diagnosis required
• Isuzu Diagnostic Service System (IDSS) induced regeneration (fast
or slow) based on diagnosis may be required for the 7.8L Isuzu
Diesel
• Slow process takes 2 hours
GM bulletins are intended for use by professional technicians, NOT a “do-it-yourselfer”. They are written to inform
these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the
proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how
to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or
that your vehicle will have that condition.

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Document ID: 2398614

#PIP4602A: Slips Will Not Shift Or May Overheat SES / MIL May Be Illuminated DTCs P0218 P0894 Or P0741 – keywords slip TCC – (Feb 12, 2010)

Subject: Slips, Will Not Shift or May Overheat, SES/MIL May Be Illuminated, DTCs P0218, P0894 or P0741
Models: 2009 Chevrolet Express 2009 GMC Savana
Equipped with HYDRA-MATIC® 4L80E (RPO MT1) or 4L85E (RPO MN8) Automatic Transmission
This PI was superseded to add DTC P0741. Please discard PIP4602.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Customers may comment that the transmission slips, will not shift, or may overheat. Technicians may find DTCs P0894, P0741 or P0218 stored either current or in history. These conditions may be caused by friction material debonding from the Torque Converter Clutch.

Recommendation/Instructions:

If any of these conditions are observed, the friction material from the Torque Converter may have circulated throughout the transmission, the cooler lines, and the transmission cooler. Remove the transmission oil pan and inspect for friction material in the filter. If friction material is observed in the trans pan or filter, the torque converter is the possible cause and it will be necessary to disassemble the transmission completely for a cost comparison (include a torque converter and filter in the estimate). Refer to service bulletin 08-07-30-001 for cleaning and inspection instructions of the valve body assembly. After the cost comparison either repair or replace the transmission in the most cost effect way. If it is necessary to replace the transmission contact the PQC at the number you have been provided.

Important Note: It is critical that all internal transmission components are thoroughly cleaned and the transmission cooler be flushed using the J 45096 transmission oil cooling system flush and flow test tool. It is also critical that the system be flushed in both directions to capture any friction material trapped in the cooler. Be sure to back-flush first to push material out of the cooler, following the instructions provided with the J 45096.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

Document ID: 2692337

#PIT5006B: Residual Power Steering Fluid Diagnosed As Leak At Hydraulic Brake Booster – (Jul 21, 2011)

Subject: Residual Power Steering Fluid Diagnosed as Leak at Hydraulic Brake Booster
Models: 2003-2006 Cadillac Escalade Models
2003-2006 Chevrolet Avalanche, Suburban, Tahoe
2003-2012 Chevrolet Express Van, Silverado Classic, Silverado 2003-2012 GMC Savana Van, Sierra Classic, Sierra
2003-2006 Yukon, Yukon XL, Yukon Denali, Yukon Denali XL 2003-2007 Hummer H2
With Hydraulic Brake Booster
This PI was superseded to update condition concern field and model years. Please discard PIT5006A.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some customers may comment there is power steering fluid leaking at the front of the hydraulic brake booster. The hydraulic brake booster is filled with power steering fluid and tested after assembly. During this test procedure, power steering fluid can get on the outside of the hydraulic brake booster and may not get cleaned off after the test procedure is completed. Once the brake booster is installed on the truck the power steering fluid left on the outside of the brake booster will run down and collect at the bottom of the booster. This fluid may lead you to believe the hydraulic brake booster is leaking and unnecessarily replace the booster.

Recommendation/Instructions:

When diagnosing a leak around the hydraulic brake booster clean any power steering fluid off the outside of the booster. Then add power steering dye to the system and use a black light to check for leaks.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

Letter from Chevrolet

We have learned that your 2011 model year Chevrolet Express, equipped with a 10.5 inch rear axle, may have a condition in which the rear axle right-hand side bearing adjuster clip and bolt may come loose within the rear axle. If this occurs, a grinding noise and a vehicle vibration would be noticeable when the vehicle is in motion. If the adjuster or bolt punctures the differential cover pan, a fluid leak could develop. If enough fluid were to leak out, you may hear increasing noise, additional vehicle vibration, and smell burnt axle lubricant. If these warnings are ignored and the vehicle continues to be driven, a slow loss of vehicle motion could occur.

Your satisfaction with your Express is very important to us, so we are announcing a program to prevent this condition or, if it has occurred, to fix it.

What We Will Do: Your Chevrolet dealer will inspect and, if necessary, repair the rear axle. This service will be performed for you at no charge until April 30, 2014. After that, any applicable warranty will apply.

What You Should Do: To limit any possible inconvenience, we recommend that you contact your Chevrolet dealer as soon as possible to schedule an appointment for this repair. By scheduling an appointment, your dealer can ensure that any necessary parts will be available on your scheduled appointment date.

If you have any questions or concerns that your dealer is unable to resolve, please contact the Chevrolet Customer Assistance Center at 1.800.222.1020 (TTY 1.800.833.2438).

Courtesy Transportation: If your vehicle is within the New Vehicle Limited Warranty, your dealer may provide you with shuttle service or some other form of courtesy transportation while your vehicle is at the dealership for this repair. Please refer to your Owner Manual and your d~aler for details on courtesy transportation.

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