Identifying F23 vs F35 Transmission

Last updated: Nov 18, 2025 by Adam Doyle

The F23 and F35 are the two manual transmissions that came in the Chevrolet Cobalt. In general, base-model and sport models use the F23, while SS models use the F35. Whether you are checking to see if your car had its transmission swapped or you are looking at buying a replacement transmission, the following information can help you identify which transmission you have.

F23 Transmission

Things to look for:

All three transmission mount bolt holes are on the same horizontal plane. (left side of photo, notice the flat arrangement of bolt holes)
Shifter arms have two counterweights.
End cover is a flat, stamped metal plate.

Chevrolet Cobalt F23 transmission showing flat stamped end cover, two shifter counterweights, and mount holes aligned on the same plane. — F23 transmission: flat stamped end cover, two counterweights, and mount bolt holes aligned evenly.

F35 Transmission

Things to look for:

Transmission mount bolt holes sit on different planes; one bolt hole is lower than the others. Note: The F35 normally uses an aluminum adapter bracket that bolts to the transmission and includes the three top bolt holes. If you are missing that bracket, we offer a replacement that works in the Goblin: F35 Mount Adapter
Shifter arms have one counterweight.
End cover is a 3D cast shape rather than a flat plate.

Chevrolet Cobalt F35 transmission showing uneven mount bolt heights, a single counterweight on the shifter arm, and a 3D cast end cover. — F35 transmission: mount bolt holes on different planes, one counterweight, and a 3D cast end cover.