1972 subframe removal question - for someone who has done it

[Kenyon Wills]

I am interested in removing/reinstalling the front subframe on my 1972 Imperial.

My question is:

After suspension and steering box are stripped off and engine/transmsision are removed, does the subframe merely unbolt from underneath, or do I need to disassemble the hood/fenders/grille/bumper/rad support first?

I can't tell how I'd support the weight of the car in the air without the subframe, so I am supposing that I'll have to strip the car down to the firewall and place padded jackstands somewhere that isn't the subframe somewhere just under the firewall area?
I doubt that anyone's done this so much with Imperials, so I'm asking the regular C-body group, and I'd appreciate answers based on experience over hypothesis please.



Photo is of the car using solar radiation to stretch out and relax the new not-yet-installed vinyl top.

Thanks in advance.

 

[Samplingman]

Here is how I did mine. First, strip down the nose, fenders hood, rad support, etc.

Then build a rolling support that will span the pinchwelds of the car.

Next support the front with Jack stands at the pinchwelds, and also by the stub frame.

Then remove the bolts supporting the stub and lower the frame down.

Roll the frame away.

Roll the support structure under, Jack the support up to remove the stands and you are done.

 

[Kenyon Wills]

Excellent, illustrated answer - thank you.

 

[Owen11x]

Also. Never and I mean never remove the transmission cross member without letting all the tension off the torsion bars. If you have weak or rusty body mounts taking that crossmember out without turning torison bars down entirely that's the way you're going to find them in a hurry!

 

[Clayboy]

Here is how I did mine. First, strip down the nose, fenders hood, rad support, etc.

View attachment 652924

Then build a rolling support that will span the pinchwelds of the car.

View attachment 652919

Next support the front with Jack stands at the pinchwelds, and also by the stub frame.

View attachment 652920

Then remove the bolts supporting the stub and lower the frame down.

View attachment 652921

Roll the frame away.

View attachment 652922

Roll the support structure under, Jack the support up to remove the stands and you are done.

View attachment 652923

Did you document the rest of your restoration? If so, I would be interested in seeing more pics/hearing about it. Thank you.

 

[Samplingman]

Did you document the rest of your restoration? If so, I would be interested in seeing more pics/hearing about it. Thank you.

Sure, it’s a work in progress. Here is the thread. I still have to update the rest of last year’s work.

Resurrection of my 1970 Chrysler 300 Convertible

 

[Clayboy]

Great. Thank you. I am sure other members will find this interesting and useful. Good luck.

 

[MoPar~Man]

Sure, it’s a work in progress. Here is the thread. I still have to update the rest of last year’s work.

Resurrection of my 1970 Chrysler 300 Convertible

So what you have is a 1970 300. Looking at your frame photo's, I don't see what are supposed to be differences in the 1970 frame vs 1968 and earlier frame in terms of the body isolation mounts. If these isolators exist, they seem to not need any modification of the frame. I mention all this because I'm curious about what exactly the differences are in the FRAME between the 1968 to 1970 (or laterr?) cars.

 

[Samplingman]

So what you have is a 1970 300. Looking at your frame photo's, I don't see what are supposed to be differences in the 1970 frame vs 1968 and earlier frame in terms of the body isolation mounts. If these isolators exist, they seem to not need any modification of the frame. I mention all this because I'm curious about what exactly the differences are in the FRAME between the 1968 to 1970 (or laterr?) cars.

Good question. The frame that is in my car now is actually from a 1969 Dodge Polara. These are solid mount frames, no rubber isolators that are found on ‘70-‘73 hardtops. There is a great thread on here that dives into great detail about the differences between solid mount and torsion quiet, just do a search on “sub (stub) frame” and it should come up.

Back to the question, I have studied many pictures of frames and looked at different FSM measurements and I see no difference in the actual mounting from year to year. However, I do know that there are subtle differences in how accessories are attached, the way the fuel line is routed and the way the emergency brake cable is mounted. It didn’t require a great deal of mods, just drove me nuts thinking I had the wrong parts. I’ve detailed some of these issues in my thread. Best thing to do is spend some time at the next Chrysler Nationals, and get under some cars with a tape measure and your camera and start documenting, that’s what I did (with the owners permission of course). Good luck!

 

[71Polara383]

I think. In theory you could leave the front clip on and drop the frame out.

 

[1970FuryConv]

Excellent, illustrated answer - thank you.

So what you have is a 1970 300. Looking at your frame photo's, I don't see what are supposed to be differences in the 1970 frame vs 1968 and earlier frame in terms of the body isolation mounts. If these isolators exist, they seem to not need any modification of the frame. I mention all this because I'm curious about what exactly the differences are in the FRAME between the 1968 to 1970 (or laterr?) cars.

Jim's 1970 300 is a convertible. 1970 was final year for convertible. Also, 1st year for isolated subframe. Since it was final year of convertible, convertible subframes for 1970 are the same as earlier years. Convertibles had non-isolated subframes.

To complicate matters, other (non-convertible) Chrysler and Dodge c-bodies changed over to isolated subframe in 1970. Plymouth changed to isolated subframe in 1971.

Isolated subframes are completely different, because they have a separate rear mount, while non-isolated do not.

Kenyon: to answer your question, for my 1971 Fury, I installed the Isolated subframe with fenders, radiator support, and hood still in place.
My 1971 Plymouth Isolated subframe. Rear mounts

Borrowed this non-isolated subframe pic from @Samplingman thread mentioned above
See, no rear mounts. Does not need the rear mounts because it is tight with no isolators.

I used a board and hydraulic jack to lift my isolated subframe

I hope that helps with your questions

 

[MoPar~Man]

The '70+ frames with the rear mounting extensions - are they mounted to the body in 6 places? Or 4? As far as the isolators go, are used in all mounting positions or just the 2 rear extensions?

Sort of a side-question- 1969 is considered the first fuselage year for C-bodies? But it shared the exact same subframe as the slabs going back to '65 or '66 ?

Would there be a problem separating the subframe from the body with the engine/trans still bolted in? If you wanted to roll the subframe to a different location to take the engine / trans off?

 

[Kenyon Wills]

Jim's 1970 300 is a convertible. 1970 was final year for convertible. Also, 1st year for isolated subframe. Since it was final year of convertible, convertible subframes for 1970 are the same as earlier years. Convertibles had non-isolated subframes.

To complicate matters, other (non-convertible) Chrysler and Dodge c-bodies changed over to isolated subframe in 1970. Plymouth changed to isolated subframe in 1971.

Isolated subframes are completely different, because they have a separate rear mount, while non-isolated do not.

Kenyon: to answer your question, for my 1971 Fury, I installed the Isolated subframe with fenders, radiator support, and hood still in place.
My 1971 Plymouth Isolated subframe. Rear mounts
View attachment 653335
Borrowed this non-isolated subframe pic from @Samplingman thread mentioned above
See, no rear mounts. Does not need the rear mounts because it is tight with no isolators.
View attachment 653336
I used a board and hydraulic jack to lift my isolated subframe
View attachment 653337View attachment 653338
I hope that helps with your questions

That adds questions.


What I think that I see in the photo is:

1. Body and all non-subframe components hanging in space, cantelevered off of the body shell. Where does it all fasten? Through the fenders? Did you leave the bumper on? Those things weigh as much as three wives, so that can't be.

2. 4 jackstands supporting the body shell, with a 4x6 distributing the load on the floor up front, and the pinchwelds in back while some tires or wheels do something mysterious in the center - surely you were not insane and left the transmission in, no, it could not be THAT. What job are the tires doing?

3. Plywood skid used to jack-lift the freshly painted subframe into place for re-fastening.

-----------

To the other poster, yes thank you for the reminder on the T bar tension. I have rebuilt about 8 Imperial front ends over time, and I have car-nal knowledge of the system, but the reminder will be heeded. I'll remove the LCA's first, which will lead to bar removal prior to subframe removal

 

[detmatt]

From page 15 to around page 23 is stub frame work on my ‘67 Imperial.
So I bought this one today.

 

[1970FuryConv]

The '70+ frames with the rear mounting extensions - are they mounted to the body in 6 places? Or 4? As far as the isolators go, are used in all mounting positions or just the 2 rear extensions?

Sort of a side-question- 1969 is considered the first fuselage year for C-bodies? But it shared the exact same subframe as the slabs going back to '65 or '66 ?

Would there be a problem separating the subframe from the body with the engine/trans still bolted in? If you wanted to roll the subframe to a different location to take the engine / trans off?

1970 and later isolated subframe's are mounted to the body at 6 places, 4 under the body shell and 2 under the radiator support panel. Isolators are used in all mounting positions.

1965 subframe is one year only. Engine mounts are different. 1966 through 1969 are the same.

You can lift the car and drop the engine, transmission, and subframe as a unit.

 

[1970FuryConv]

That adds questions.


What I think that I see in the photo is:

1. Body and all non-subframe components hanging in space, cantelevered off of the body shell. Where does it all fasten? Through the fenders? Did you leave the bumper on? Those things weigh as much as three wives, so that can't be.

2. 4 jackstands supporting the body shell, with a 4x6 distributing the load on the floor up front, and the pinchwelds in back while some tires or wheels do something mysterious in the center - surely you were not insane and left the transmission in, no, it could not be THAT. What job are the tires doing?

3. Plywood skid used to jack-lift the freshly painted subframe into place for re-fastening.

-----------

To the other poster, yes thank you for the reminder on the T bar tension. I have rebuilt about 8 Imperial front ends over time, and I have car-nal knowledge of the system, but the reminder will be heeded. I'll remove the LCA's first, which will lead to bar removal prior to subframe removal

it fastens at 4 places under the body shell floor and at 2 places under the radiator support panel. The bumper fastens to the subframe via the brackets. I removed the grill and bumper as a unit before removing the subframe.

You can call the tires a safety measure, but you could also call them a storage area. I removed the transmission and engine before removing the subframe. I also removed the suspension before removing the subframe. The jacks are under the rear subframe and under a small crossmember that supports the front floor.