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Discussion Starter · #1 ·
is there a difference in strength between 80-81 and 82-96? someone called 80-81 frames swiss cheese frame. does that mean its a weak frame? is there a way to strengthen it?
thanks
 

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As you can see in the picture on Steve's post, there are large holes in the frame and this is generally referred to as the "Swiss Cheese" frame. Raising fuel consumption concerns caused auto companies to lighten their vehicles as much as they could (which is why a '79 Bronco weighs around 6500 lbs and an '80 Bronco weighs around 5000 depending on accessories. My '81 weighs 4000.) One of the means to lose weight was to cut large holes in the frame.
However, after just a year of this, the frames were folding and collapsing under conditions that would normally not be a problem, like accidentally hitting a curb and finding your front tire twisted 180 degrees. They quickly realized that this was going too far and stopped doing it.

So, long story short, yes, avoid any with the swiss cheese frame. Fortunately they are very easy to spot with a quick peek under the skirt and can easily be avoided. Keep in mind, however, that some '80 and '81s may not have them. With a stroke of luck, my '81 has a full strength frame.

The only way to fix it would be to, as suggested, swap out the frame, or to go the long route and cut and weld steel back into all the holes and weld on support brackets where needed.
 

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Discussion Starter · #3 ·
i have way to much done to my 80 to swap frames so ill try and stiffin it up. thanks guys.
 

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The other difference (but looking at your avatar pic it probably won't matter) is that 80-81 the TTB pivot bracket for the drivers side beam is welded in palce instead of being bolted in place. That's why a lot of TTB lifts say for 81+ instead of 80+.

Justin
 

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Discussion Starter · #6 ·
TTB

The other difference (but looking at your avatar pic it probably won't matter) is that 80-81 the TTB pivot bracket for the drivers side beam is welded in palce instead of being bolted in place. That's why a lot of TTB lifts say for 81+ instead of 80+.

Justin
i never noticed if it was welded or bolted. does that mean they dont make a lift for 80s? i guess you could cut it off and bolt on the drop arm.
 

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Discussion Starter · #7 ·
Frame

I'll sell you another frame.
thanks but i actually just bought a 93 for interior parts and to part out so if i get crazy which i wont i could use that frame. its just way to much work. ill keep working with what i have,add some more supports and fill some holes hopefully itll be ok. im supprised it hasnt busted already. im not that nice to it plus it has a lot of torque.
 

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Discussion Starter · #8 ·
Bracket

...or bolt & weld the drop bracket on, like the front dropped panhard bar bracket for early Broncos. ;)
yep that sounds like a winner. well guess i have a lot more work to do like there isnt enough. just when i think im getting caught up something like this happens. :duh
 
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