* Interconnected Failure: The motor and regulator are closely linked. If the motor has failed, it's quite likely that the regulator has experienced some wear and tear as well. Replacing only the motor might lead to a premature failure of the newly installed motor because it's working with a worn-out regulator. The strain on the new motor could burn it out quickly.
* Labor Costs: Removing the door panel and accessing the window regulator and motor assembly is the most labor-intensive part of the job. Since you've already done the work to get to the components, replacing both at the same time saves labor costs compared to doing it twice. The extra cost of the regulator is often minimal compared to the labor savings.
* Preventative Maintenance: Replacing both ensures that the entire system is functioning optimally and extends the life of your window system.
In short: While technically possible to only replace the motor, it's generally recommended to replace both the motor and regulator assembly for a more durable and reliable repair. If the regulator is clearly damaged (cracked, broken, or excessively worn), this is even more important. Inspect the regulator carefully before deciding; if it looks questionable, replace it.
