Anyone know how to replace it?
Anyone heard of one failing ?

Hate to buy a new pump just cause the freakin gauge crapped out...

Contact Topeak directly. They were helpful in providing a small bracket that I needed with my RoadMorph pump. Their reputation on this forum is that if you call them they can help. Just recently boutght a TwinHead floor pump upgrade and the information sheet says contact Todson @ #1-800-213-4561. Good Luck.

Called them. Short answer- new guage and replacement instructions in the mail, no charge.

Topeak is my new favorite company...

The Joe Blow replacement gauge costs less than $9. It is part number TRK-G13, https://www.topeak.com/global/en/pro...-kit/456-gauge

I need a replacement because I destroyed the old gauge trying to remove it to fix an air leak around the gauge assembly. Your pump may be different, but on my pump the metal cup of the gauge screws into the vertical shaft. It looks like the right thing for me to have done would have been to remove the clear plastic gauge cover, hold the gauge's metal cup, and rotate the shaft counterclockwise to unscrew. Once the gauge cup is unscrewed, the shaft pulls out from the bottom. You might be able to repair an air leak by replacing the O-rings at a hardware store and greasing them. Do not open up the gauge by removing the dial, because it is impossible to get it all back together again. The threads where the gauge cup screws into the shaft appear to have some kind of sealant, pipe dope, or Loktite.

On the replacement gauge (probably a newer design) the shaft appears to be integrated with the gauge. It looks like you can simply push the gauge assembly upward to gain access to the O-rings, if an air leak is suspected. I don't know because the replacement gauge is currently out of stock.

The shaft of the gauge has a hole that has to line up properly with the pump body in order to pass air. If the gauge isn't working, or the pump isn't easily passing air, make sure the shaft is properly aligned. Remove the hex bolt on the end of the gauge assembly. If you don't see the shaft hole centered in the hex bolt hole, rotate the shaft and attached gauge. Then tighten the hex bolt.

x2 I just wished they had certain items yet to be developed/provided by them that others may have; Which I found those "others"are @ a less desired quality & does not serve for purpose as intended.