engine mounts?
 

I noticed that the driver's side engine mount's main bolt (the huge one that you can get to from underneath the car) was loose. I tried to tighten it with a 1/2" breaker bar but had no luck. I soaked the heck out of it with WD-40 and let it sit for a few hours...I beat on it with a hammer...tried to tighten it again...nothing will budge the darn thing! And it's a fairly new motor mount, only 20,000 miles on them. I replaced them both when I put the new motor in just a few years ago. The bolt & nut still look like new, no rust or corrosion. I was lifting up the right side of the motor with the big bolt even moving up and down a little in the slot it goes through in the chassis, and nothing will budge. Even tried to loosen it some, and then tighten it. Still nothing. Any clues on how I can crank this engine mount down tight with out using a cherry picker to lift, or move the motor around some? I'm stumped.

Hmmm. It sounds like you may have cross threaded it or something.

If it were me I would take the nut back off and chase it with a thread tapp and then try it again with some lube.

Later,

engine mounts
 

No, it's definitely not cross-threaded. That bolt & nut are pretty frickin huge. I don't even know if it's possible to cross-thread it. But I specifically remember everything went smoothly when I put the new motor & mounts in. Tightened up smoothly just like it should. I just didn't think it would come loose, let alone...not be able to retighten it!
Anyone have a miracle technique or a solvent or something I can spray on there to help free up the nut??!! :confused:

What may of happened is you pulled some of the threads loose from the shaft of the bolt from a few hard launches.

Jack up the car and remove the tire so you can get to it good and break that sucker loose.

Once you remove the nut your problem should become obvious.

Good luck,

engine mounts
 

I finally got the nut off! :D Boy was that a *****! Threads are all ok. Guess I'll be using some loctite on both of them now.