PIT3271G

Bulletin No.: PIT3271G
Date: Jan-2015
Subject:
Guidelines When Changing Tire And Wheel Size
Models:
2003-2015 All General Motors Light Duty Trucks / Utilities / Vans
This PI was superseded to update Model Years. Please discard PIT3271F.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Changing of tire size on midsize and full size trucks and utilities.
Recommendation/Instructions
When attempting to change tire size, it is important to understand what tire size the customer is interested in installing. General Motors will ONLY support a tire
calibration for tires that have been sized, tested and designed for the vehicle in question and its applications. DO NOT use the information offered in the ABS
module (tire size selection) as a guide to see what tires are applicable to the vehicle in question. Keep in mind, changing the tire size in the ABS module will only
affect ABS wheel speed sensor calibration that are direct inputs to the ABS module. It will not correct or calibrate the speedometer's accuracy, and will not
change the calibration of the ABS rear speed sensor value on vehicles that obtain rear wheel speed data from the ECM/PCM/VCM via the VSS.
Example:
2004 Chevrolet Colorado LS with 235/75/R15 tires. The customer would like to install P265/75/R15 tires. Although ABS module shows this tire can be
programmed, the 265/75/R15 will only fit under a Colorado with the Z71 suspension. This suspension will offer acceptable wheel clearance. Therefore, a
calibration will not be offered for this application.
Example:
A second example would be the latest version of TSB 03-03-10-006 or 06-03-10-011 - which offers 20" or 22" wheels and tires for the full-size trucks. A
calibration has been developed for these specific applications in response to popular demand from our customers. Accessories released an approved tire
wheel combination that has been tested and validated by GM Engineering for a specific application.
The only way to confirm that a calibration is available would be to visit YOUR sales department. Using the sales order guide, the following combinations of items
must be available for the vehicle in question. If you can build a vehicle, using the sales guide, using the same model year, body style, engine size, transmission
type, axle type and suspension type, any tire offered for that combination will have a corresponding calibration available.
If your sales guide does not cover the model year vehicle that is in question, please contact the Techline Customer Support Center (TCSC) (English: 1-800828-6860, French: 1-800-503-3222).
Please do not call Technical Assistance Center for these concerns. Once the tire application has been confirmed per the sales guide, contact TCSC to
determine calibration availability.
Note: There may be a cost to the customer for this service. This is NOT a feature that is covered under the manufactures warranty.
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.
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. See your GM dealer for information on whether your vehicle may benefit from the information.
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