Its Back: GM Fixed Our 2027 Chevy Bolt’s Noise Issue

Since delivery of our 2027 Chevy Bolt in February, I’d noted an occasionally annoying noise from the drive train. (See 2027 Chevy Bolt Odd Noise at Low Power Levels.) This didn’t affect how we used the car, but it was annoying after driving EVs for 12 years without any similar noise.

Thus ensued a round of visits to the local Chevy dealer, starting a case with GM’s EV concierge, and several weeks driving GM rentals as the dealer’s service tech and GM engineering traced the source of the problem with a PicoScope. (See 2027 Chevy Bolt: Diagnosing Noise Issue with a PicoScope.)

20260430 grants pass 464 — Our 2027 Chevy Bolt charging at a Mercedes-Benz High-Power charging station near Ashland, Oregon in 2026.

The good news is they found the problem, replaced the drive motor, and the car drives and sounds like what we’ve come to expect from EVs. That is, it’s quiet.

The Chevy dealer’s work order said they opened a GM TAC (Technical Assistance Center) Case 92106742 on the noise problem and that they contacted TAC Case 95949345. Subsequently they followed Document ID: 675573 for drive motor replacement, ID: 7001623.

Ouch.

I don’t know how they replace the drive motor, but I suspect they have to pull out the whole inverter and drive motor stack to get at the drive motor.

On the work order’s list of parts they replaced is “24071551 module 1,” which may be the drive motor. Online parts dealers list the part for between $2,000 and $3,000 though no pictures or diagrams are available. So that sounds about right.

They replaced the drive motor, performed “auto coolant fill” three times, drove the car for 30 miles, and reported no noise. They then let the vehicle set overnight; rechecked fluid levels, drove the car again, then released it to me.

The repair was covered under warranty.

With the noise issue out of the way, and solutions to other annoyances, our 2027 Bolt is now performing as expected.