What do you recommend to use to clean rust from threads
 

Like the title says what should I use to decontaminate the threads on the frame of the car?

Try a dremel with a wire wheel and safety glasses.

Lol I don't want to try I want to be sure I won't screw up the threading

We use a wire wheel to clean threads on bolts and other external threads in my auto class works great... but another option if ur carful is to use a thread chaser to clear rust that is in the groves of the thread and just let it stand like that.

I appreciate it man. Ill try the wire wheel

If ur worried start with brass wheel.

a wire wheel on a bench grinder. usually a grinder side and cleaning side. is the best bet. like he said. you cant go wrong that way. thats what i use. doesnt hurt anything

Thanks for the great info... Just don't want to fuck anything up...

a wire wheel works perfectly if the rust is not too severe. Also running the threads with a die never hurts, but make sure its the right thread pitch.

A tap?

Wire wheels work great, but can be dangerous. Try holding parts with Vise-Grips. Better is a vibrating parts cleaner, and you don't have to stand in front of a wire wheel for extended periods. You get up in the morning and the parts are clean. Sandblasting works great. Try Metal Rescue. Best new product out there, but it only removes rust. It does not remove grease or paint. It does leave a protective coating on the cleaned part that lasts for months if you can't get around to painting things.

I'm confused by the OP. Are you trying to clean the bolt holes on the frame of your car? If so I can't think of anything other than a tap.

If you are cleaning bolts off of your car than a wire wheel or a parts tumbler (my preference) or media blaster (overkill for bolts).

wire wheel

I was talking about the bolt holes in the frame but now that I have a new shell I dont think it'll be necessary. At least if i do come across it I'll just use a tap. Thank you