2007 GMC Yukon

You have to recalibrate the EBCM with a tech 2 scan tool for the new size tires.

Its the electronic brake control module, its the brain of the ABS system. It has to be recalibrated when bigger or smaller wheels are put on, because the ABS reads wheel speed, so changeing to a bigger size will cause ABS activation because a bigger wheel rotates slower causeing an inacccurate reading, if its calibrated it will read normal and no problems will occur.

Yes you still will need to recalibrate, because you are changing to a taller and wider tire. It will affect ABS function because the EBCM reads wheel speed and a taller wider tire will spin slower and could cause unwanted ABS activation so recalibrating will prevent this problem, it doesnt take long to re-calibrate, I would call a local GM dealer and explain what you are doing and if they are a good dealer they should be able to take care of it at a normal price.

Well, yes and no, because they have to be GM OEM wheels and the dealer has to get a VCI number from GM which is a recalibration number to accept that size tire and they can down load it into the vehicle. This info might help: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.A second example would be 20" wheels and tires for the full size pick up trucks. A calibration has been developed for this specific application 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 the rims are aftermarket they might not have a calibration because GM does not support aftermarket products just OEM.I"ve gone through this with other people on there vehicle, its a pain in the butt. Might want to call another dealer, might get a different answer.

Yes you would have to choose between OEM and aftermarket, but GM dosent support the software for aftermarket wheels.I was suggesting calling another dealer they might help more than the last one. As far as the software update you cant buy it because only GM dealers have access to it and is not made for the general public. If you go with aftermarket wheels you might get lucky and find a company that does this or OEM wheels and going to the dealer. There is not much beyond this, its the only info. There is not much else I can suggest.