Frame differences, 1969 vs. 1974?
Thread Starter
Instructor
Joined: Jun 2007
Posts: 205
Likes: 1
From: Miami, FL
Frame differences, 1969 vs. 1974?
I just bought the frame restoration guide in the books & manuals section, and I was curious why the title says 69-72. It has been my belief that the frame didn't change substantially until 1975, which would make the book apply to 69-74.
Other than the age of the welds, what are the differences between a 69 frame & 74 frame?
Thanks,
Chris
Other than the age of the welds, what are the differences between a 69 frame & 74 frame?
Thanks,
Chris
Instructor
Joined: Dec 2004
Posts: 236
Likes: 0
From: Clearwater Florida
73 is a one year only frame. The crossmember at the very back is the same as the 69-72. The body mounts are a different height to account for the rubber body mount cushions. 69-72 did not use rubber body mounts. The front frame horns are drilled different for the crash bar on the rubber bumper 73.
74 is also a one year only frame. The front frame horns are the same as 73. The body mounts are the same as the 73. The cross member at the very back is different than the chrome bumber 69-73 cars. The 74 had a rubber rear bumper and it mounted to the frame different.
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
The rear crossmember is the same the last 14" of each frame rail is different for the 1 year only 5 Mph bumper.
Instructor
Joined: Dec 2004
Posts: 236
Likes: 0
From: Clearwater Florida
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
69-72 are the same and will interchange.
73 is a one year only frame. The crossmember at the very back is the same as the 69-72. The body mounts are a different height to account for the rubber body mount cushions. 69-72 did not use rubber body mounts. The front frame horns are drilled different for the crash bar on the rubber bumper 73.
74 is also a one year only frame. The front frame horns are the same as 73. The body mounts are the same as the 73. The cross member at the very back is different than the chrome bumber 69-73 cars. The 74 had a rubber rear bumper and it mounted to the frame different.
73 is a one year only frame. The crossmember at the very back is the same as the 69-72. The body mounts are a different height to account for the rubber body mount cushions. 69-72 did not use rubber body mounts. The front frame horns are drilled different for the crash bar on the rubber bumper 73.
74 is also a one year only frame. The front frame horns are the same as 73. The body mounts are the same as the 73. The cross member at the very back is different than the chrome bumber 69-73 cars. The 74 had a rubber rear bumper and it mounted to the frame different.
I have a 73 frame that I'm using for my 72 so I will know shortly if the front holes are different, but I think I'm just going to use solid mounts again to keep the body as close to the frame as possible. I'm probably going to have ride height issues anyway with an aluminum engine.
Rick B.
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Thread Starter
Instructor
Joined: Jun 2007
Posts: 205
Likes: 1
From: Miami, FL
Where does one get 'engineering drawings'?
Anyone have pictures to share of these differences?
Any reference sources for exact details?
Anyone have a contact at NCRA who might have docs?
I only ask because I bought a 69 body and a 74 frame (not yet in possession or ya, I'd just look at it). If I'm SOL in mating them, it'd be nice to know...
Thanks again!
Chris
Anyone have pictures to share of these differences?
Any reference sources for exact details?
Anyone have a contact at NCRA who might have docs?
I only ask because I bought a 69 body and a 74 frame (not yet in possession or ya, I'd just look at it). If I'm SOL in mating them, it'd be nice to know...
Thanks again!
Chris
Melting Slicks
Joined: Oct 2002
Posts: 2,865
Likes: 1
From: I may be getting old but I refuse to grow up
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Where does one get 'engineering drawings'?
Anyone have pictures to share of these differences?
Any reference sources for exact details?
Anyone have a contact at NCRA who might have docs?
I only ask because I bought a 69 body and a 74 frame (not yet in possession or ya, I'd just look at it). If I'm SOL in mating them, it'd be nice to know...
Thanks again!
Chris
Anyone have pictures to share of these differences?
Any reference sources for exact details?
Anyone have a contact at NCRA who might have docs?
I only ask because I bought a 69 body and a 74 frame (not yet in possession or ya, I'd just look at it). If I'm SOL in mating them, it'd be nice to know...
Thanks again!
Chris
Rick B.
Team Owner
Joined: Jun 2000
Posts: 38,923
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From: Southbound
Cruise-In II Veteran
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
I've measured the height of the body mount brackets on 69-74 frames and have not found any difference in height. The 74 frame has two plates and two hoops welded at the rear corners. They can be removed to work on 69-73.
Mike
Mike
Melting Slicks
Joined: Jan 2012
Posts: 3,034
Likes: 503
From: myrtle beach sc
Army
I have a GM replacement frame on my 68 coupe. It was listed as fitting 1968-1974. As Trackdogg2 has said, only the outer corners had different add on's, that I removed. My car was twenty years old at the time, and I found out that three months later they were discontinued!!! I really got lucky. Lou.