'92 Frame Cancer Help!

Northwoods SC

Registered User
I need some help as I'm way out of my league with this problem. Being a Northern car and having been driven as a daily driver in Michigan for 10 years of it's life, my '92 SC now has a terrible case of frame rot, to the point where one of the subframe brackets has rotted through and detached. I have new brackets, but there just isn't any decent metal left to attach them to the frame. Other than the rockers being totally gone, the front half of the car frame is in much better shape than the rear. A mechanic advised that half of a donor frame could be welded in, but I'm leary of that. What year and type of Thunderbirds (regular or SC) would fit anyway?

Has anyone attempted a repair such as this or ever heard of it being successful? I've got some $$ in the rebuilt engine - it runs great/strong now and the body and interior is in nice shape, just the frame issue. Trying to save my 20 year old baby - had it all this time. Would a car from the South be a better option? How would the costs compare between a weld in frame approach vs. getting a donor car with no frame rust and using my engine and body?

Here are some pics from when it was on the rack. Thanks for any and all advice.

http://webpages.charter.net/northwoodsmusic/
 
The problem with the frame suggestion is that there isn't really a "frame" on the T-Birds - they are unibody cars, which basically means that the body shell provides the structural support for the car. There are sub-frames on these cars, but I doubt anyone has had them rust through (rear sub-frame and front K-member).

If it's just a daily driver, I wouldn't worry too much about those brackets. I've driven a couple of SC's where those brackets were rusted off, and I never experienced a problem. If racing, I think that would be another story.

If you want to fix the rust problem you have, it would probably be cheapest / best to find a good body and just swap anything you want to keep into the new car. If you were to replace the rear half of the car, you might as well to a short-bodied modification while you're at it! :eek:
 
That piece that rotted out is just a bolt-in bracket. In theory, it is easily replaced, the only problem is that the bolt that goes through the actual rear subframe is probably rusted to the captive bolt inside the frame rail. If it doesn't come out, you will need to cut an access hole in your frame to get a wrench in there to hold the nut from spinning while you take the bolt out, and that is assuming the bolt doesn't break off. From the looks of it, the rest of the structure of the car is OK, that looks like just surface rust. The rockers are another story, and from the looks of it, those are completely gone. If your only concern right now is getting it back to being safely drivable, then it is worth fixing. If you are looking to have the car in perfect shape again, then you would be better off finding a rust free shell and swapping in your engine, interior, etc.
 
You have whole sections of underbody completely missing. Not worth fixing. Drive it until you find a suitable donor car and then take a couple weeks to swap over everything good and just junk the northern body. Southern cars are as clean underneath as the day they were made. Fixing rust is a no-win proposition because for every bit you see, there is an equal or greater amount that is hidden.
 
Wow, glad I don't live in the rust belt. Is that from salt? We use Magnesium Chloride here, almost no rust on the ol' bird. Crazy…..

I think you can buy those brackets from Ford still.
 
Yeah, I suspect road salt is the main culprit, and probably a few winters stored outside on grass. As far as swaps are concerned, can you lift the bodies off these frames? Would any year SC or XR7 work as a frame/shell or the fact that it is a unibody design limit me? Trying to decide if pulling the motor/trans and transplanting is my only option. Would love to keep the body.

For safety sakes, I assume from the comments so far that it would not be a problem to drive this now in its current rusted state?
 
As far as swaps are concerned, can you lift the bodies off these frames?

No - with the unibody design, there is no real frame - the body and "frame" are the same thing. Without extensive work, I don't think the body can be saved.

For safety sakes, I assume from the comments so far that it would not be a problem to drive this now in its current rusted state?

I don't think it is dangerous to drive...as long as nothing is falling off and the subframe mounting points are still strong, I think it is probably safe.

If you want to fix the rust problems, getting a new body is the only realistic option.
 
The car is a unibody, so it has no frame. The body of the car is what creates the structure of it, and yours is rusting away. So in short, no there is no way to swap the body to another frame. As far as what to use, a 91-93 would be the easiest swap. 89/90 would also be fairly easy, but would have some slight wiring differences if you were planning on putting your dash into the donor car. 94/95 would work, but would require changing some parts around. If it was my car, I would look for a clean 89-93 SC that has blown head gaskets, or a blown motor, or a beat interior, or something where the car is complete but has some kind of mechanical problem. That way the donor car will be cheaper, and it will be cheaper and easier to get it back on the road compared to buying a car that is missing major components.
 
Thanks for the education, guys! If any of you lived closer, I'd share a few pints of my homebrew with you. As difficult as it is to hear that there is no real cure for the old girl, I guess getting a solid one and swapping in what I need isn't too daunting. What sort of price range might a good donor car attract this day and age? Would an LX body be an option for that engine/tranny?
 
I hate to say it but I agree with everyone else. Time to find a new chassis.

Though one thing it keep in mind is there is only 4 mounting points for that IRS so if you plan on driving it for a little while longer then make sure that the other points are going to hold up. From the way it looks to me it better to take it for one last ride and then park it till tear done time.:(
 
Us northerners drive our cars till the wheels collapse under us. He's got a long ways to go before he has to park the car. ;) The worst part is when something needs servicing under the car and you can't get any bolts out. Then you are stuck. The key is to find a better car before any major undercarriage work is required.
 
I have a 92 that I am considering parting out. Been a Texas car all of it's life and doesn't have a spot of rust on it. It's had some body work on the passenger quarter panel and the core support is a touch wavy. If you wanted the shell, I would sell it cheap. Depending on how much of the car you wanted. I would take $1500 for the whole car, $1000 if I keep the engine/tranny, $500 if I keep the engine/tranny/wheels/hood/seats.
 
Pic of my brackets

DSC_5930-1.jpg

I may have some more if you want.
 
An LX would work, but would require more work and wiring to swap all the SC goodies onto. Just keep an eye out for any 89-93 SC with a clean body and the swap should be pretty painless. As far as a price, it depends on the condition of the car, but you should be able to find a clean rust free body with major mechanical problems for under $1000.
 
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