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Unnecessary Engine Crankcase and Subsystems Flushing Services, Additive Recommendations and Proper Utilization of GM Simplified Maintenance Schedule to Enhance Customer Service Experience

Subject:Unnecessary Engine Crankcase and Subsystems Flushing Services, Additive Recommendations and Proper Utilization of GM Simplified Maintenance Schedule to Enhance Customer Service Experience

Models:2008 and Prior GM Passenger Cars and Trucks (including Saturn)
2008 and Prior HUMMER H2, H3
2005-2008 Saab 9-7X



This bulletin is being revised to add model years. Please discard Corporate Bulletin Number 04-06-01-029A (Section 06 -- Engine/Propulsion System).


An Overview of Proper Vehicle Service

General Motors is aware that some companies are marketing tools and equipment to support a myriad of engine crankcase and subsystem flushing procedures. These dedicated machines are in addition to many engine oil, cooling system, fuel system, A/C and steering system additives available to the consumer. GM Vehicles under normal usage do not require any additional procedures or additives beyond what is advised under the former Vehicle Maintenance Schedules or the current Simplified Maintenance Schedules. Do not confuse machines available from Kent-Moore/SPX that are designed to aid and accelerate the process of fluid changing with these flushing machines.

Engine Crankcase Flushing

General Motors Corporation does not endorse or recommend engine crankcase flushing for any of its gasoline engines. Analysis of some of the aftermarket materials used for crankcase flushing indicate incompatibility with GM engine components and the potential for damage to some engine seals and bearings. Damage to engine components resulting from crankcase flushing IS NOT COVERED under the terms of the New Vehicle Warranty.

GM Authorized Service Information: Detailed, Descriptive, and Complete

If a specific model vehicle or powertrain need is identified, GM will issue an Authorized Service Document containing a procedure and, if required, provide, make available, or require the specific use of a machine, tool or chemical to accomplish proper vehicle servicing. An example of this is fuel injector cleaning. Due to variation in fuel quality in different areas of the country, GM has recognized the need for fuel injector cleaning methods on some engines, though under normal circumstances, this service is not part of the maintenance requirements.

GM has published several gasoline fuel injector cleaning bulletins that fully outline the methods to be used in conjunction with GM Part Numbered solutions to accomplish proper and safe cleaning of the fuel injectors with preventative maintenance suggestions to maintain optimum performance. You may refer to Corporate Bulletin Numbers 03-06-04-030 and 04-06-04-051 for additional information on this subject.

Subsystem Flushing

Flushing of A/C lines, radiators, transmission coolers, and power steering systems are recognized practices to be performed after catastrophic failures or extreme corrosion when encountered in radiators. For acceptable A/C flushing concerns, refer to Corporate Bulletin Number 01-01-38-006. Flushing will remove metal fragments and safeguard new components. This practice is NOT required or recommended for normal service operations.

Service Is Important to You and Your Customer

General Motors takes great pride in offering our dealerships and customers high quality vehicles that require extremely low maintenance over the life of the vehicle. This low cost of ownership builds repeat sales and offers our customers measurable economy of operation against competing vehicles. Providing responsible services at the proper intervals will greatly aid your dealership with repeat business, and additional services when required. Most customers appreciate and gain trust in the dealership that informs and offers them just what they need for continued trouble-free operation. Examine your service department's practices and verify that all Service Consultants and Technicians focus on customer satisfaction, vehicle inspections, and other products at time of service. Use this opportunity to upgrade the services you provide to your customers. Here are a few suggestions:

    • Take the time required to align your dealership service practices with the new GM Simplified Maintenance Schedule launched with the 2004 models (in Canada, the GM Merchandising Maintenance Process launched with the 2003 models). Use the new vehicle Owner's Manual Maintenance I and II schedules (in Canada, use the "Warranty, Maintenance and Owner Assistance information" booklet and the vehicle's "Owner Manual" Maintenance Schedule) to create a "mirror image" in your advertising and dealer service pricing that is easily understandable to your customer. Taking advantage of this new service strategy may greatly increase your dealership service sales and customer retention while decreasing the frequency of visits and inconvenience to your customer.
    • Review your program to ensure that all vehicles coming in are evaluated for safety and wear items. Examine all vehicles for tire condition, signs of misalignment, brake wear, exterior lamp functionality, exhaust condition, A/C cooling performance, SRS or Air Bag MIL, along with Service Engine Soon or Check Engine indicators. If the Service Engine Soon or Check Engine MIL is illuminated, it is vital that you inform the customer of the concerns with ignoring the indicator and what the required repair would cost. In addition to the possibility of increased emissions and driveability concerns, many customers are unaware that lower gas mileage may also result, with additional cost to the customer.
    • Be complete in your service recommendations. Some sales opportunities are not being fully pursued nationally. Focus on overlooked but required maintenance that has real benefits to the customer. Many vehicles are equipped with cabin air filters. If these filters are used beyond replacement time, they may impede airflow decreasing A/C and heating performance. Make sure these filters are part of your recommended service. Note that some of our vehicles may not have been factory equipped but will accept the filters as an accessory.
    • Express the value in maintaining the finish quality of the customer's vehicle at the Maintenance I and II visits (in Canada, Semi-Annual and Annual Service inspections). More fully utilize the vehicle prep personnel you already have in place. In today's world, many people simply ignore the finish of their vehicle, at best infrequently using an automatic car wash for exterior cleaning. Offer vehicle detailing services in stages from just a wash and wax to a complete interior cleaning. When paired with the Simplified Maintenance (in Canada, the Semi-Annual and Annual Service) visit, this will increase customer satisfaction. On return, the customer gets a visibly improved vehicle that will be a source of pride of ownership along with a vehicle that is now fully maintained. Also, reinforce the improved resale value of a completely maintained vehicle.
    • For customers who clean and maintain the appearance of their vehicles themselves encourage the use of GM Vehicle Care products. Many customers may have never used GM Car Wash/Wax Concentrate, GM Cleaner Wax or a longtime product, GM Glass Cleaner, which is a favorite of many customers who try it just once. If your dealership give samples of these products with new car purchases, customers may already be sold on the product but not willing to make a special trip to the dealership. Capitalize on sales at this time. Stock shelves right at the Service counter with these products and consider instituting compensation programs for Service Consultants who suggest these products. Many consumers faced with an intimidating wall full of car care products sold at local auto parts stores may find it comforting to purchase a fully tested product sold by GM that they know will not harm the finish of their vehicle. We suggest these competitively priced basic vehicle care products to emphasize:

In USA:

      • #12378401 GM Vehicle Care Wash/Wax Concentrate 16 fl. oz. (0.473L)
      • #89021822 GM Vehicle Care Glass Cleaner Aerosol 18 oz. (510 g)
      • #12377966 GM Vehicle Care Cleaner Wax 16 fl. oz. (0.473L)
      • #1052929 GM Vehicle Care Chrome and Wire Wheel Cleaner 16 fl. oz. (0.473L)
      • #12378554 GM Vehicle Care Odor Eliminator 16 fl. oz. (0.473L)

In Canada:

      • #10953203 GM Vehicle Care Wash & Wax Concentrate 473 mL
      • #992727 GM Glass Cleaner Aerosol 500 g
      • #10952905 GM Vehicle Care Liquid Cleaner/Wax 473 mL
      • #10953013 GM Vehicle Care Chrome Cleaner and Polish 454 mL
      • #10953202 GM Vehicle Care Wheel Brite 473 mL
      • #88901678 GM Vehicle Care Odor Eliminator 473 mL
    • Display signboards with the installed price for popular GM Accessories such as running boards and Tonneau Covers. Customers may not think to ask about these desirable items at the time of a service visit.
    • Finally, take advantage of the GM Goodwrench initiatives (Tire Program, Goodwrench Credit Card, etc. / Dealer Marketing Association (DMA) Promotions in Canada) to provide the customer with more reasons to identify your dealership as the best place to go for parts and service.

Remember to utilize ALL of the service aspects you possess in your dealership to satisfy and provide value to your customer. Many businesses exist profitably as an oil change location, a vehicle repair facility, or a detailing shop alone. You already have the capabilities of all three and provide these services with the inherent trust of your customer, under the GM Mark of Excellence.