Struggling with a seized seatpost on a 2019 Trek after trying the ammonia trick for three days straight.

The customer brought it in from a coastal town and the corrosion is so bad I'm thinking about trying a pipe wrench next, but I'm worried about crushing the tube, so has anyone had luck with a specific penetrating oil or a different removal method?

3 comments

3 Comments

oscarm243mo ago

Have you tried a mixture of acetone and automatic transmission fluid? That's what finally worked for my old beach cruiser. Apply it, let it sit overnight, then use a long breaker bar on a good quality seatpost clamp for even force.

sarah_johnson463mo ago

That acetone and ATF mix is a classic. I've had good luck adding a bit of heat too, like a heat gun on the frame tube for a minute before you try to turn it. Just don't get it crazy hot. The real trick is patience, letting that mix work its way down for a full day, maybe even giving it a few more taps with a hammer to help it creep in. A long breaker bar is key, but make sure your bike is really secure so you don't twist the whole frame.

diana551mo agoTop Commenter

Seat tube, not frame tube, yeah? I'd be careful with that heat too, warped a frame once and learned that lesson the hard way.