help, subframe bushings bolt stripped
 

84 300sd rear subframe bushings. Things were going smooth and then on the second one the main big bolt would not go in.
It seems apparant that the hole is going to need to be retapped.
One problem is that the car is sitting half in and half out of the garage.
Is it OK to take the car off of the jack stands and move it foreward or back with only one of the bolts in while I sort this problem out?
Also any thoughts on how to deal with the bolt problem?

Are you sure it's stripped? Those bolts can be quite difficult to get started. I have used a bottle jack under the bolt head to get them started.

Not sure about rolling the car with one bolt; if it were me, I'd at least have a floor jack on the subframe on the unbolted side and use that too hold the weight while rolling.

Are you sure the bolt is stripped? I messed one of these up some years back by by turning the bolt the wrong way while forcing it in with a jack. Dumb. I solved by problem by carefully cleaning the threads with a 14x1.5mm tap. This size is similiar to a spark plug thread (14mm), but the pitch is different so it might be tought to locate via normal retail channels. I got my tap by flagging down the Snap-On truck. You should probably should get a new bolt as well. Good luck.

As mentioned above, the bolts typically don't want to start because the springs are forcing the subframe down away from the body. You need to put a jack under the subframe and force it upwards.

If you must move it, it would be best if you supported the subframe with a jack, that can roll forward with the vehicle. If you lower the body down onto the wheel, some of the weight of the body will attempt to twist the subframe because the bolt is missing. While the subframe is very stiff, the opposite anchoring point is not designed for this.

If you are already on a hard surface, put the jack underneath the differential and push the vehicle, and the jack, back into the garage. Two people would be better. ;)

sounds like moving is ill advised. I closed up garage as best I could with shackle locks from inside so door can not be raised. If someone crawls under they have to crawl out.
Yep I had a jack under subframe. I tried different jack heights for different seeming sweet spots. I would hammer the bolt up and then either impact wrench or hand wrench to no good.
I swapped the screwed up bolt with the other side and it went in fine. So I have a bolt in good shape if I can get the threads to work out.
Hard to see how it stripped since it is such a deep hole through the bushing. It doesnt seem like you could mess up the angle.

How tight should this bolt be? Should it be as tight as an impact wrench will make it?
The topper is the bushings I took out looked in pretty good shape and probably didnt need to be bothered with. They were withing 1/4 inch of the same height of the new ones.

I thought the same thing when I replaced mine. But there was a noticable improvement in handling, plus it lifted the rear end a good bit.

85 ft.-lb. for the large bolt.

Do not use an impact wrench. :eek:

This is not a Chevy. ;)

14mm by 1.5 tap did the trick. I got it back together pretty quick after that. I measured 3/4 inches higher on each side after the new bushings.