For 1990-2009 cars

# Underbody Corrosion - keywords appearance body frame rust

Subject: | Underbody Corrosion

Models: | 1999-2008 All GM Light Duty Trucks

| 1999-2008 GM Passengers Cars

This PI was superseded to update Model Years. Please discard PIT3749A.

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

### Condition/Concern:

This message pertains to underbody corrosion in general. Although corrosion of underbody components has no detrimental effect on vehicle operation, some customers, particularly on those vehicles with high visibility such as the HUMMER H2 may ask to have it addressed.

### Recommendation/Instructions:

A number of GM Dealers have reported success with the use of POR-15 (or equivalent). It can be applied directly on a rusted surface, provides excellent appearance, is very durable and has longevity. For additional information and to order POR-15, go to one of two locations, www.stoprust.net or call (866) 351-7878 or go to www.POR-15Store.com or call (877) 548-9323.

Please do not call Technical Assistance for additional information. Technical support, order quantities and pricing are available directly from the supplier.

It is extremely important to follow all directions, warnings and cautions provided with POR-15.

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.