Determining window balance replacement part

Home Owner from Santa Clarita, CA

Mar 24, 2025 4:32 pm

My window balance has the following stamped on it: 26 4 GT CMC 2
I'm trying to determine what would be the correct replacment part. Thanks.

4 Replies

Emily from SWISCO

Mar 26, 2025 3:03 pm

Hi there!

Thank you for reaching out to us. Can you upload photos of your balance removed from the window? We specifically would like to see up close shots of the top and bottom fittings. We would also like to see an image of the inside of the balance’s metal channel, where the innerspring connects to the pulley mechanism; this connection is located in the middle of the channel.

Home Owner from Santa Clarita, CA

Mar 29, 2025 7:35 pm

Thank you! See attached photos. These are two identical windows, but once has "2740" stamped on it and the balance spring is 28" long, while the other window balance springs have 26 4 GT CMC 2 stamped on them and are 27" long. The pictures attached are from that window. Could two different sizes (28" and 27") both be able to work? Thanks!

5 user uploaded images

Emily from SWISCO

Mar 31, 2025 1:49 pm

Your balance looks like it could be a match for the S380-27 or S385-27, depending on the depth of the bottom shoe. You'll have to measure as shown below to determine the best pick.

Since the windows are identical, they should have the same stamps and configuration. As a rule of thumb, however, we like to recommend sticking with whatever hardware the window originally had. Has either window ever given you any issues with opening and closing it?

Can you give us the visible glass height of each window sash? We would also like you to weigh each sash and tell us the precise weight.

Comparison of the S378, S380 and S385 balance shoes.