TAC Tech => Mechanical => Topic started by: d_hache on March 22, 2021, 05:39:34 AM

Title: Removing the front subframe connector bolts (Spinning)
Post by: d_hache on March 22, 2021, 05:39:34 AM
Hello everyone, I have an 1980 Trans Am and was trying to take the front sub frame out this weekend.  I am down to the last four bolt connecting the subframe to the chassis.  I have been spraying them with W40 all week hoping they would come out smoothly but no such luck.  All 4 bolts are spinning but not coming out.  What options do I have specially with the back ones since I seams to have access to the top part. 

Thanks in advance
Title: Re: Removing the front subframe connector bolts (Spinning)
Post by: roadking77 on March 22, 2021, 06:58:21 AM
Simplest thing is to drill a hole in the floor.  I figured out the location from measuring a couple of points and got it really close. Then drilled a 2" or so hole saw, all but through, flipped the metal up, you can then access the loose nut, when finished you can bend the tab back down and hit with a spot weld, or just seal it up good with some brushable seem sealer from the local auto part store.

(https://live.staticflickr.com/65535/50026610648_6e57487b22_c.jpg) (https://flic.kr/p/2jdFsrN)2020-06-20_05-17-19 (https://flic.kr/p/2jdFsrN) by Kerry Grubb (https://www.flickr.com/photos/156399515@N07/), on Flickr
The front mounting holes for the seat track were a good reference point.  X marks the spot
(https://live.staticflickr.com/65535/50027148406_ce5bd0c978_c.jpg) (https://flic.kr/p/2jdJdiu)2020-06-20_05-17-11 (https://flic.kr/p/2jdJdiu) by Kerry Grubb (https://www.flickr.com/photos/156399515@N07/), on Flickr

As soon as the drill breaks through, lean it to one side so not to cut all the way through the entire piece

(https://live.staticflickr.com/65535/50027410182_406ee6bd46_c.jpg) (https://flic.kr/p/2jdKy7S)2020-06-20_05-17-00 (https://flic.kr/p/2jdKy7S) by Kerry Grubb (https://www.flickr.com/photos/156399515@N07/), on Flickr

Bingo!  The culprit exposed. Should be able to get ahold of the nut at this point.

Good Luck!
Title: Re: Removing the front subframe connector bolts (Spinning)
Post by: roadking77 on March 22, 2021, 07:01:25 AM
For reference, in the above pic, the cage nut was intact. I only did this to apply pb blaster to loosen things prior to removal. It worked great as I soaked it for about a week in advance and the bolt came right out. I got a bit smarter on the other side and only drilled a 1/4" hole directly over the nut. I was able to spray the blaster into the small hole, again worked great and I only had a small hole to patch, not a weld job.
Title: Re: Removing the front subframe connector bolts (Spinning)
Post by: Wallington on March 22, 2021, 08:31:17 AM
Great pics. Also, be aware in the vast quality difference of some new cage nuts for this application. Some are thin and weak and threaten to crack just torquing up, and then a few are the extra heavy gauge type. Price probably tells which is which.
Title: Re: Removing the front subframe connector bolts (Spinning)
Post by: d_hache on March 22, 2021, 09:29:01 AM
Great info TY will let you know how it goes
Title: Re: Removing the front subframe connector bolts (Spinning)
Post by: Fbird on March 22, 2021, 11:49:40 AM
or...do not remove anything....1 hand dandy cut.....'

https://nastyz28.com/threads/body-bushings-replacement-how-to-with-tips.251412/