It usually costs between $1,800 and $3,400 for a Chevy Express 2500 transmission replacement just for the part, and an additional $800 to $1,000 for added cost of a mechanic’s labor. All in all, you’re looking at paying somewhere between $2,600 and $4,400.
But, before you commit to the idea that you need your entire transmission replaced, first a) whether you need a full replacement or just a repair and b) if you do need a full replacement, if it makes financial sense to do so.
Next, have a mechanic take a peek at your transmission and see if the problem is something more minor like a leak—which costs between $150 and $300 to repair. If your mechanic determines that there’s no fixing it and replacement is truly your only option, it may make more sense to get a new vehicle if yours is older and nearing the end of its life.