I have some rear shackles that I need to remove from the leafs & the nuts are solid tight & I dont want to break em off & ruin it. My nut cracker is broken so can I heat the nut with the hot wrench cherry red then remove it or will that weaken the bolt? thank you for your time

The shackle is just cold roll material

It'll be fine. If in doubt, replace the nut.
Doug

I worried that if I heat the nut cherry red that it will weaken the bolt that it is on. Am I worried over nothing?

I use strong heat when nothing else works. Since you are going to heat them, try this first. Heat them enough so that they start to smoke, something other than burning off road debris. When hot enough, melt wax from the top down, crayon works. The wax runs down the threads and allows for the break. Works 90% of the time. If not, you are close to half way there with the heating.

Your over thinking it.. heat it up

Rubber/urethane bushing? I wonder if it's true. I was told if you breathe burning urethane it will kill you.

Fuel tank is right there Robert, so be careful.

Just heat the nut, not the bolt.

the nut is on the other side of the shackle flat piece so I think I'm good on the fumes (if I work fast). I dont have a crayon handy so I will go ahead & heat it up. Thanks guys

either one inhaled ain't good for you !
i use the heat/wax, birthday candle, crayon trick all the time. that works GREAT ! i removed all the tiny slot screws from the cowl vent screen from my 1933 dodge "humpback" panel delivery project using this method, and half of them had the screwdriver slot in the screw head almost rusted away.

Put the fire to the flat side of the nut until it shows some color and spin the nut off. Don't use your fingers... lol.

If it doesn't go well, new shackles aren't that expensive.

Kevin

X2 on using wax. I use gulf wax, never had rusted nut or bolt not come apart. Just heat & apply nurmerous times.

Maybe you should consider getting a new nut splitter?

Never really needed one for 45yrs.

PB Blaster is a good product to help get stuff apart...if it's salvageable. Sometimes new parts are the correct answer.

I'll get on it, I appreciate the advice/help. Thank you!

Sometimes, two heat cycles will work. I used to work at and asphalt plant and most of it was bolted together. Everything rusted. We would heat the nut to the point that some color appeared and then let it air cool. Then we would heat it up again and put a wrench on it. I don't know why it worked, it just did.

I couldn't find a nut splitter on hand locally so I will try that

That candle trick is pretty slick. Or give it a good soaking in Aero-Kroil.....

I had a stuck nut on a shackle and it was rounded over. I took my MIG and welded two wings on the nut so a ViceGrip had some thing to grab on to. This got the nut real hot. While still very warm I sprayed PB Buster on the threads, let cool and it spun off real quick. Then just replaced the nut with a stainless steel one.