53 convertible Flexing chassis ,cause for concern?

[Pilgrim65]

Noticed gearbox oil leak , from torque ball assembly , so bought repair kit from bobs . As concerned about oil low level in gear box , put Ruby up on friends ramp to sort . however they use swinging arm 4 point support type lift here ,noticed  drivers door popped open , unable to close ,but returned to normal when car grounded. Didn't think about any door gap issues . Yesterday took Ruby to a restoration workshop to repair torque ball oil leak problem , when they lift her they noticed quite a large widening of same door gap . Concerned they adjusted ramp and lifted again same problem  but not so bad . They Garage owner works on early American and owns 3 caddys , he inspected underside and although he commented the restoration was correct and professionally done , he says the chassis is flexing to much and thought the section size of the chassis frame could have been more substantial . He's going to strengthen the sides and thinks it will cure problem. I'm concerned door gap will never be correct ,but he's confident they willbe able to align in conjunction with strengthening . Picking car up next week will see. 

Wondered if any of you convertible owners had noticed similar problem when lifting car.

cheers

pilgrim

[Bhigdog]

Door gap on my 55 century convert opens a little when on lift. Doors still open and close normally. The convert frame  is thicker and heavier, especially the X member, to compensate for a lack of roof. Is it possible that a closed body frame was used for the restoration?..............Bob

[Pilgrim65]

Bob , interesting thought , wonder how I could check ,would the correct size and thickness of channel section be listed anywhere .

i d be surprised if it where the case as there is no evidence of cost cutting anywhere else., apart from vinyl instead of leather, which I doubt would have been original on special anyway . Thanks for your input , on the case ?

Cheers

pilgrim

 

[Bhigdog]

Size of the chassis is the same (at least for 55 and 57).  For my 55 restoration I used a hardtop parts car. I can say for a fact the X member thickness  difference  is apparent with out actually measuring it. Hopefully someone with a 53 buick will actually get under their car and measure the thickness of the X member and side rails for you............Bob

[60FlatTop]

I used to do quite a bit of front suspension and steering work on old cars. If one positions jackstands under the cowl you can see the front bumper drop 3 to 4 inches below normal when the jack is released. Knowing that, I rarely allow any of my old cars on a two post lift. When I go for inspection or need something checked they always send me around to the back door and the four post drive-on lift.

 

They all flex. I rode a light aircraft carrier for a year or so. You ought to stand at the rear of the flight deck and watch what that does.

 

I would say to check the frame, especially boxed areas, for pitting or cracks, otherwise some flex is normal and I wouldn't worry about the gap change. Just don't let them leave in on the lift while waiting for parts.

Bernie

[old-tank]

4 minutes ago, 60FlatTop said:

I used to do quite a bit of front suspension and steering work on old cars. If one positions jackstands under the cowl you can see the front bumper drop 3 to 4 inches below normal when the jack is released. Knowing that, I rarely allow any of my old cars on a two post lift. When I go for inspection or need something checked they always send me around to the back door and the four post drive-on lift.

 

They all flex. I rode a light aircraft carrier for a year or so. You ought to stand at the rear of the flight deck and watch what that does.

 

I would say to check the frame, especially boxed areas, for pitting or cracks, otherwise some flex is normal and I wouldn't worry about the gap change. Just don't let them leave in on the lift while waiting for parts.

Bernie

What Bernie says...

They ALL flex, even my 55 4-door hardtops when on a 2-post lift which I stay away from.  If yours has good and consistent gaps when on the wheels and you avoid ramp jumps, then leave it alone.  Spend you time and money elsewhere.

[60FlatTop]

I just clicked the the "Found on vaction" topic and found the wrong way to support.

 

Lots of weight forward of the cowl. Front stands should be under the A-frames or that area. Rear stands don't make a lot of difference because of less weight. I wouldn't be too fussy about the rear.

Bernie

[Pilgrim65]

Thanks guys , some great advice , actually picking up tomorrow so will post .

[60FlatTop]

Always be careful of the two most dangerous words in the English language "I thought". But when you hear them it is usually too late.

Bernie

[dei]

My '58 Special convertible flexes a lot too but always has.

One actually has to be careful on placing your hand on the door spaces when going down an uneven road as it can pinch a bit if fingers are in the right spot.  

My frame is not rusty, ever had repairs of any kind or in an accident so have considered it the nature of the beast.

I do know my Limited with her extra length in the trunk and the bigger frame being a two door hardtop always gave me a more solid feel and ride.

As suggested, checking for any cracks at welds would be the evidence of something more serious.

[Pilgrim65]

29 minutes ago, dei said:

My '58 Special convertible flexes a lot too but always has.

One actually has to be careful on placing your hand on the door spaces when going down an uneven road as it can pinch a bit if fingers are in the right spot.  

My frame is not rusty, ever had repairs of any kind or in an accident so have considered it the nature of the beast.

I do know my Limited with her extra length in the trunk and the bigger frame being a two door hardtop always gave me a more solid feel and ride.

As suggested, checking for any cracks at welds would be the evidence of something more serious.

Cheers Dei, comforting to know , not unique and evident on others peoples cars , not so concerned now.

pilgrim

[Beemon]

You have to consider that the car and frame are suspended from the A-arm and rear axle suspension. When you unsprung those components, the car is suspended by the frame, which is made from thin wall components, hence the ability to flex. If you didn't know, steel is very elastic and will retain it's original shape if you don't put exceeding amounts of stress on the members. It's one of the reasons why they detach pickup beds from the cab. There should be nothing to worry about unless the frame is made to fatigue. Always suspend from the A-arms and rear axle when lifting, as those members are engineered to take up the weight load.

[Bhigdog]

Yes, they all flex when suspended from the frame, converts more so. The OP noted that the flex was sufficient to pop open a door which would not re-latch while the car was on the lift. Another shop noticed "quite a large gap" in the door(s) margin when on the lift. This not normal. Both my Buick converts show less than a 1/8" flex at the top of the door margin and the doors will open and close normally when on the lift . 

I'm suggesting there are unknown  issues with body or frame. 

Possibilities could include hinge adjustment, broken frame weld, wrong frame, loose, missing, or improper body mounts or a combination or some of all of the above.

Personally I don't think I would weld patches on the frame to correct an unknown cause. 

But that's just me...........................Bob

 

Edited October 27, 2017 by Bhigdog (see edit history)

[avgwarhawk]

They all flex.   The sprung weight on the chassis while on the ground is how the body  panels/doors were aligned.   When lifted at points that do not allow the body to sit on the springs as designed the chassis flexes and panels start separate.  Doors do not work like they should.   Once back on the ground all is as it should be.      

[Bhigdog]

14 minutes ago, avgwarhawk said:

They all flex

 

I think we all agree on that but not to the point where doors pop open and will not latch or the door margins open to the point that they draw unsolicited concern..  Just sayin........Bob

[dei]

Not to belabour the point but...

When I had a blowout this summer and jacked up the car with the factory bumper jack I dammed near cringed watching the bumper come up and press on the bottom of the cast grill getting the tire high enough off the ground to get my spare on! 

I know this is the reverse of hanging on a hoist but to demonstrate the "flex" in a convertible, notice the angle of the bumper and the fender gap at the top of my passenger door.

I did not try to open it (no need) but once back on the ground things lined up and the doors operate normally. 

 

[Bhigdog]

Bumper jacks are spawn of the devil. What you are looking at is the flex of the bumper, frame ends , and bumper brackets. Nothing to do with closed vs convert frame flex. Just sayin.............Bob

Edited October 27, 2017 by Bhigdog (see edit history)

[dei]

Hmmm..

Hanging the car "off the tire / springs" at the corner of the front frame/bumper brackets has no effect?

OK, I'm not too old yet to learn something new Bob. 

[Bhigdog]

Of course it has an effect. I think we all agree the frame flexes when it's loaded/unloaded  in various ways. In the present situation we are discussing if the observed flex, as described by the OP  is excessive and abnormal. Going by what I observe with my 2 convertibles, lifted in the approx same way as the OP's, I think his frame flex is excessive and not normal.

 

My comment about what you observed when bumper jacking was trying to point out that your situation was not the same as OP's. No slight intended...............Bob

 

 

[Bleach]

When I owned my 67 Cadillac convertible I always had used the bumper jack to lift it to change a tire. I learned if I needed to get something out of the car for whatever reason I had to make sure I kept a door unlatched otherwise there was no way to open it. Also if a door was opened there was no way to close it if the car was jacked up that way. You could really see it flex with a open door but it never had any door gap issues with all 4 wheels on the ground.

My 51 Cadillac hardtop was also the same even though it had a permanently attached roof.

[Pilgrim65]

Thanks again guys , will be staying away from 2 post lifts !!

Concerning bumper jacks , had never seen one before until I found mine in boot of Ruby , I have two occasions to use and both times , been a nightmare , they go up ok , but release under load is big problem , have had to loan scissor jack or garage type from friend , to take weight and enable release,  otherwise Ruby would be still flashing her underside ! 

Furthermore think stress on bumper may actually damage chrome.

not being to critical of GM or whoever invented , but not the greatest of designs ,  think a few of you Americans must have had similar experiences changing a wheel, can't imagine how the fairer sex managed with them. ( perhaps they didn't ,but used charm instead ?)

Edited October 28, 2017 by Pilgrim65 (see edit history)

[60FlatTop]

6 hours ago, Pilgrim65 said:

Thanks again guys , will be staying away from 2 post lifts !

 

"By George, I think He's got it!"

Just the a little of the British perspective.

[Fr. Buick]

I always travel with a small floor jack in the trunk.  The factory one is too risky and prone to cause damage.  It's good only for showing off the trunk compartment...

Edited October 28, 2017 by Fr. Buick (see edit history)

[old-tank]

One of my favorite stories:

 Fifty plus years ago someone wrote to Tom McCahill, automotive writer for Mechanix Illustrated: "Why is it you spend $5,000 on a car and get a crummy $1.50 bumper jack"?
His answer: Because they ran out of fifty cent ones".

[NTX5467]

Many people perceive that a  "frame" is strong and stiff, but it's really quite flexible by itself.  3/4 ton pickups are better.  Look at an earlier Corvette and you'll see "stiff", but not nearly as stiff as the current pickup truck chassis.

 

In those earlier times, part of "the ride" was the frame/body flexibility and why driving on a country road usually would result in more weatherstrip squeeks than if you drove on a highway all of the time.

 

Dad had a '51 GMC pickup.  As a normal situation, he's drive diagonally across terraces at the farm.  The steering column was attached to the frame (via the steering gear).  The flex would eventually crack the lower instrument panel where the steering column mount was. 

 

Similar body/'frame flex issues are still in newer vehicles, as "high-cube box vans on 2500 chassis.  When I got the first one, inherited from a former employee, there was lots of wind noise around the front door.  When it was replaced with a new one, it was quiet.  Past the cab, it was two frame rails, with crossmembers, and stiff springs.  Rather easy to put it into "torsion bend" driving into and out of business entrances.  So I would drive out at a 90 degree angle to the street, once the front wheels were there, then I'd turn.  This let the front suspension be where the pivot points were, rather than the stiffer rear springs being where the pivot was, which put more bending forces into the long frame rails.  The front door seals were quieter for much longer doing that little deal!  Fewer other issues with noise and rattles, too.  If you drive thorough those elevation changes "normally" it's the frame rails that take the torsion rather than the suspension.

 

The old Weaver twin post lift the local Chrysler dealer used to have, back then, was very neat!  The rear wheels had their spots, then the front lift was moved to match the lower control arms.  As each had individual controls, had to be careful in letting the car down!  Had to slow the front as the rear descended independently (usually slower).  The drive-on "muffler shop" lift is pretty good . . . as long as you don't bump your head or run into the front and/or rear suspension lifts it can have!

 

NTX5467

 

 

[NTX5467]

Many people like to put "solid" or urethane body mounts in place of the factory rubber items, not unlike they desire to do in the front suspensions.  ONLY problem is that the cars were designed to have "points of greater flex" and places of "lower flex".  IF the particular location is a "pivot" with impact absorption as the main reason for the rubber, that's different than if the place is supposed to absorb flex and interrupt metallic noise routes to the body.  Taking flex away from some places (via more solid mountings) only transfers it to places it was not designed to be.  Whether actual bending or undamped harmonics in other places, making things more solid can give the impression of greater solidity, but can also cause issues later on with metal fatigue from the addition forces being where they weren't meant to be.

 

To be sure, frames can be strengthened with additional metal reinforcements, gussets, and such.  Just as using sub-frame connectors can decrease body flex in unit body vehicles.  Just as long as appropriate body/frame and suspension rubber isolation is maintained where it needs to be.  PLUS adherence to the "factory jacking locations" happens!

 

Some vehicle construction orientations are stronger/stouter/less flexible than others.  Each has their design benefits and detractions (which need minimizing at the design level).  Levels of execution can vary from manufacturer to manufacturer and how much they desired to spend on these things.  OR how proud they wanted to be of what they'd done!

 

NTX5467

[1953mack]

On ‎10‎/‎27‎/‎2017 at 12:30 AM, Pilgrim65 said:

. . . The Garage owner works on early American and owns 3 caddys , he inspected underside and although he commented the restoration was correct and professionally done , he says the chassis is flexing to much and thought the section size of the chassis frame could have been more substantial . He's going to strengthen the sides and thinks it will cure problem . . . he's confident they will be able to align in conjunction with strengthening . . . 

 

You might want to spend some time and do a little research to determine whether or not you have an OE 1953 open or closed-car frame under your Model 46C. Judging from the garage owner’s comment, I doubt that he could answer that question or explain to you the differences, if there were any. Owning three Caddys doesn’t mean anything to me except that he might be looking for contribution$ for a fourth one.

 

Buick did not add stiffener plates to the [-shaped side rails of a closed-car frame to turn it into a convertible frame. The 1953 46C frame has its own part number . . . different than all other 1953 40-Series closed-car Models. What is the difference?  Typically on convertible frames during the 1950s, Buick added inner and outer body-to-frame brackets for additional body support in the door latching area on convertible bodies (B-pillar area on closed cars). In 1953, Buick added steel plates welded to the underside of the X-member to strengthen the 50-70 Series open cars and Estate Wagon frames. Some prior years might have these plates also.  I do not know for sure whether 40-Series convertible frames had these plates and if they didn’t, why Buick eliminated them for this Model. 1953 Buick frames for 50-70 Series are obviously different due to the V8 engine and body dimensions. In addition, the removable rear fenders on the 50-70 Series Models might have been a contributing factor to the number of additional inner and outer body brackets; whereas, all 40 Series Buicks had integral rear quarter panels that should have strengthened the body tub assembly. 

 

Does your frame match the picture of the 1953 Buick 40 Series frame in the 1953 Buick Shop Manual and shown in the first picture below? The picture might be deceiving. I say that for several reasons: (1) the 1953 46C Model was introduced months after the production run started and information on this Model didn’t show up in many pieces of original Buick showroom literature or in the 1953 Salesman's Facts Book; (2) the picture does not note if it is applicable to either an open or closed car; and (3) the 1953 Buick Shop Manual or Service Bulletins do not explain why the Model 46C has its own part number. The explanation could have been overlooked.   

 

Two questions:  (1) What do you have for inner and outer body brackets compared to what is shown in the first picture, and (2) does your frame have the steel plates welded to the underside of the X-member? Once you know that information, you need to compare information with another 1953 46C owner with a known original frame. That’s the only way you’re going to find out. Any additional Information on this matter is most likely non-existent.  I’d be interested in what you find out.

 

Al Malachowski

BCA #8965

"500 Miles West of Flint"   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited November 2, 2017 by 1953mack
noted kick-up [ ] detail on 50-70 frames...second picture (see edit history)

[Pilgrim65]

2 hours ago, 1953mack said:

 

You might want to spend some time and do a little research to determine whether or not you have an OE 1953 open or closed-car frame under your Model 46C. Judging from the garage owner’s comment, I doubt that he could answer that question or explain to you the differences, if there were any. Owning three Caddys doesn’t mean anything to me except that he might be looking for contribution$ for a fourth one.

 

Buick did not add stiffener plates to the [-shaped side rails of a closed-car frame to turn it into a convertible frame. The 1953 46C frame has its own part number . . . different than all other 1953 40-Series closed-car Models. What is the difference?  Typically on convertible frames during the 1950s, Buick added inner and outer body-to-frame brackets for additional body support in the door latching area on convertible bodies (B-pillar area on closed cars). In 1953, Buick added steel plates welded to the underside of the X-member to strengthen the 50-70 Series open cars and Estate Wagon frames. Some prior years might have these plates also.  I do not know for sure whether 40-Series convertible frames had these plates and if they didn’t, why Buick eliminated them for this Model. 1953 Buick frames for 50-70 Series are obviously different due to the V8 engine and body dimensions. In addition, the removable rear fenders on the 50-70 Series Models might have been a contributing factor to the number of additional inner and outer body brackets; whereas, all 40 Series Buicks had integral rear quarter panels that should have strengthened the body tub assembly. 

 

Does your frame match the picture of the 1953 Buick 40 Series frame in the 1953 Buick Shop Manual and shown in the first picture below? The picture might be deceiving. I say that for several reasons: (1) the 1953 46C Model was introduced months after the production run started and information on this Model didn’t show up in many pieces of original Buick showroom literature or in the 1953 Salesman's Facts Book; (2) the picture does not note if it is applicable to either an open or closed car; and (3) the 1953 Buick Shop Manual or Service Bulletins do not explain why the Model 46C has its own part number. The explanation could have been overlooked.   

 

Two questions:  (1) What do you have for inner and outer body brackets compared to what is shown in the first picture, and (2) does your frame have the steel plates welded to the underside of the X-member? Once you know that information, you need to compare information with another 1953 46C owner with a known original frame. That’s the only way you’re going to find out. Any additional Information on this matter is most likely non-existent.  I’d be interested in what you find out.

 

Al Malachowski

BCA #8965

"500 Miles West of Flint"   

 

 

 

 

 

 

 

 

 

 

 

As usual AL, great information, very helpful and greatly appreciated.

will compare info with Ruby next week and post 

 

 

[NTX5467]

Good information on the frame differences.  Only thing is that relying upon a factory part number to define the differences, by itself, can be problematic.

 

There can be one stamping used in a particular application.  IF that same stamping can also be used/adapted to another application by the adding of brackets or even bolt holes, or even if a round hole is elongated, those extra labor ops and items generates a different part number.  Will the second one go in the place of the first one?  Yes, but not vice versa (due to the "adaptations" performed).  This is where the Hollander Interchange Manual can be a better source of information, which includes a "will fit if . . . " notation.

 

The other issue can be if the same stamping was used in later model years, but TWO prior different part numbers were combined as the earlier upgrades were incorporated into the next year's model's "normal" use.  IF they changed manufacturers/sources for the part, that's a different part number, too, although the two items are built to the same specs.

 

In verifying the correctness of parts, it's best to know what the item looks like and how it might be different from similar parts for the vehicle.  The closer the original part number is to the end of the production run for the model year, the more likely it's correct "to the end".  If there was something done to alter the part, even if a better vendor was contracted, done after the initial batch of supplied parts, that would generate a mid-year part number change, which would only show up in later publications of the GM/Buick parts books (these were published every quarter, if needed!).  If there were failures of the part and a TSB was issued with a new part number (and design changes), only the part number change would show up in the parts books.  In some cases, new pages for the service manuals were supplied for the dealership operatives to glue over the pages affected by the TSB.

 

Since the later 1990s, GM transitioned into an Internet-based service information system.  Only available to verified dealership employees or subscriptions via ACDelco for non-dealership entities.  This also made any changes in TSBs "Invisible", unless the new TSB noted what had changed from the original one.  Same with labor times, too, which can complicate things for dealership techs when times are suddenly altered (UNLESS you remember what it used to be).

 

With respect to the GM divisional parts books . . . the version printed and in force during the vehicle's introduction (fall of the year, or in the first quarter of the next calendar year), there was a "yellow pages" section at the very front of the catalog.  This area was for the "New Part Numbers" for the new model-year vehicles.  In later editions, they were integrated into the normal parts listings (although the "model years used" number would show it was new for that model year.

 

One other thing which happened for the 1988 model year, in the light trucks, relates to the orientation of "getting the vehicle to the end of the assembly line as least-expensively as possible for particular models and equipment."  The base engine on the C1500s was the 4.3L V-6.  With the basic equipment and factory a/c, it had a three-blade fan.  Many fleets bought these vehicles as they normally bought base 6-cylinder pickups.  Here comes the TX summer and the vehicles spent hours idling at job sites.  Overheat situations happened, where no issues had been previously.  Even some of the V-8s had overheat issues, too.  Apparently these issues were widespread as a TSB was issued and parts book listings for fans and fan clutches were modified from the original listings.

 

The TSB had the replacement numbers of the affected parts, which were reflected in later editions of the parts book.  The listings for the fans decreased to what it was on the prior models.  The number of fan clutches were also decreased.  The TSB instructed to use the "snowplow" fan clutch, which was heavier-duty in size and operation.  When I later saw a snow plow mounted on the front of a pickup, THEN I saw why a stouter clutch was needed for that additional equipment.  In two model years, the listings had "settled down" and the overhead issues were only a memory. 

 

In pricing vehicles for production, it might be felt necessary to hit a particular price points for costs to get the vehicle produced, which relates to ultimate MSRP and competitiveness against Ford and others.  In this case with the new version C/K truck for 1988, somebody probably decided a three blade fan could work in place of a 4 or 7 blade fan, which would also dictate a lighter-duty fan clutch, plus possibly some other related items, too.  The price target was "hit", so all was allegedly well until the vehicles were "in service".  In later model years, the original development costs were paid-down enough that more money could be spent on the later-spec items, I suspect.  In the DeLorean book on GM, it explained a situation where "Financial" said that a certain amount of money had to be "out" of the vehicle to get their approval, which the engineers had to do, and did by substituting some items they could still change right before the vehicle was scheduled to begin production.

 

The "part/vehicle production costs" tended to manifest itself in other ways, too, especially in Chevrolet driveshaft slip yokes.  The standard engine/trans slip yokes were lighter and less expensive to build, for example.  The same items proliferated greatly with the larger engines/transmissions/vehicle mix!  Of course, they had to be heavier-duty for the higher engine output and transmission variations, but those additional costs were a part of the engine's option price rather than the basic vehicle cost, so it was less important that they cost more.  People wanted the added power, so they paid the price, so to speak.  In reality, they could have pared the 30-something part numbers down to about 5, but it would have meant a more expensive item when a less expensive item had been.

 

Such a situation also existed with the '71+ GM B cars.  DeLorean was at Chevrolet then and GM wanted to use the front suspension from the Buick and Olds on Chevrolets, which was more expensive, but he had to do it.  Then they talked about how much more expensive a Chevy Impala was that year than the prior year.  Adjustments had to be made to maintain the desiered production price point.  This also resulted in some "like a rock" durability and strength of those areas of those cars . . . which made them a favorite with the demo derby crowd later, as I understand it.

 

These are things which the general public and auto enthusiasts are significantly insulated from, but those of us in the GM Parts side of things saw happen many times, especially part number changes in EACH model year

 

Sorry for the length.  Thanks for your time.

NTX5467

 

.

[Bhigdog]

I took a peek under my 55 and 57 small body converts this AM. I didn't get under them with a micrometer but to the eye the X member was approx 2 .5  times thicker than the side rails. I checked under my 55 Olds 2 door hard top ( the Olds uses essentially the same frame ) and the X member was the same thickness as the side rails. A quick look under your car should answer the correct frame or not question.............Bob

[195354]

All convertibles flex to some degree in fact every car will flex on a lift. I have personally used a lift on my 53 Buick Convertible and 53 Chevrolet convertible, they flex, and gaps change, doors will still open and close, never had one just open.  I just talked with an owner of a 55 Chevrolet convertible, he had a transmission removed for repair the shop used a lift, gaps changed but returned to normal on the ground.  Follow Al’s advice and confirm the frame has the stiffeners, then check your body mounts are they tight, then check for any rust in the rockers.  The floor and rockers are a big part of the structure any loose body mounts or rusted areas will contribute to flex.  

 The convertible  rocker on the inside panel just below the door latch area   has an additional stiffer that is about 18” long  it is sandwiched between the inner and outer rocker  panel look closely in this area.  Let us know what you find; I would bet the frame is correct and the body is loose on the frame.

 I am very close to completing a complete floor replacement from the A pillars to the trunk and replacing rockers on my Buick. It will surprise everyone how much the frame flex is reduced when everything is tight and working as one big structure.  It has taught me a few lessons for sure.

Steve

[RivNut]

When did Buick start stamping VIN numbers on the frame? Is it possible to verify if your frame is original to your body this way?

[retirednow]

I know the 52 that I had had the number on the frame, but it was under the wheelwell, so it was not visible on the fully assembled car

[avgwarhawk]

On 10/27/2017 at 5:15 PM, Bhigdog said:

 

I think we all agree on that but not to the point where doors pop open and will not latch or the door margins open to the point that they draw unsolicited concern..  Just sayin........Bob

Convertible....I would expect more flex than a hard top/sedan.  

Edited October 30, 2017 by avgwarhawk (see edit history)

[NTX5467]

Remember that the OEMs had to figure out ways to stiffen both the frame and body for open cars.  In an easy and inexpensive manner, using closed car items as a starting point.  Hence the additional "plates" added here and there, welded on or bolted in. 

 

Agreed that the condition of the body mount/chassis interface can be a factor in keeping everything "as designed".  Something not usually considered.  I remember when I had the subframe mounts on my '77 Camaro replaced, things were quieter and more solid-feeling.  MIght have been helped by the grade 8 bolts?

 

NTX5467

[1953mack]

On ‎10‎/‎29‎/‎2017 at 8:29 AM, Pilgrim65 said:

.....will compare info with Ruby next week and post.....

 

Another area that you might want to check out the next time you have your 46C up on a rack is the rear kick-up for the rear axle cross member. This area on Series 50-70 frames has an added [-shaped member that forms a stiffer [ ] rail for about two feet on each side of the frame that isn't shown in the Shop Manual’s picture for a Series-40 frame. Pictures in my Post #27 were edited.  

 

 

Al Malachowski

BCA #8965

“500 Miles West of Flint”

[Pilgrim65]

Picked up car , door gaps Ok , garage says rear bushes were missing between body and chassis and alignment wasn't perfect , think body had been slightly pulled to one side ,probably during shipping . They released and realigned and also fitted shims as level was slightly adrift also, must have always been like it since restoration. Hopefully all Ok now, however not going to put on a two post lift again ,so move on.

thanks for all the information.

cheers

pilgrim