1966 Radiator Support Markings

[6S280]

Reviewed some 7-8 year old posts about yellow markings across the bottom of the radiator support.  It was stated the K's represent the engine code but there was no conclusion on the D as it was found on supports marked for both K and 6-cyl engines.  Any new intelligence on what the D may represent? 

[J_Speegle]

No not that I'm aware of. No new information on the purpose or reason from any worker I've met. As before it was applied on the front cross member. radiator support or on the drivers side front inner fender panel or a couple of the locations so it could be seen from a number of angles. Found on 6 cylinders through big blocks on San Jose Mustang above the engine compartment black paint application. For 66 San Jose Mustangs 6 cylinders and non-K code 289's often didn't have a "D" on the front cross member. Most often it was on the battery box panel. Location likely reflected shift/worker assigned to that task based depending on the shift.

I've also documented (does not mean that it was used for the same purpose)  on some Dearborn during 65-70 production but not all cars like San Jose

[EdwardGT350]

markings written on frame after painting?

[Bob Gaines]

markings written on frame after painting?

The ones in the picture were done after painting .There are many that are markings done before painting for various reasons . I think those are the ones you are thinking of. Those are covered up but once the paint is strip off you can see a witness outline of the marking . Sometimes the marking can also be faintly be seen as a slightly raised outline after the sometimes thin factory engine compartment and radiator support painting was done. Many restorers excited to find the markings mistakenly display them over the black paint which is not correct.

[J_Speegle]

markings written on frame after painting?

There were markings applied to guide the uni-body assembly and paint part of the assembly which were under the body color and markings applied after body and paint to guide the second half of the assembly

Markings applied to the bare steel often soaked into the metal and spread leaving large chunky writing. After paint marks were separated from the metal so they did not spread and look more like normal hand writing

Examples

Under paint 50 plus years later




Over paint




Attempt at reproducing the under the paint application on a later model




NOTE: Not all or any of the examples may be specifically 66 Shelbys. The pictures were chosen to illustrate the application and affects of both methods of application described above and in Bob's reply. Please don't borrow markings from other vehicles randomly as it often leads others copying the same markings on to their car - compounding the chance that they will be copied again and again by people who assume they are correct and believe they were original to your car. Also paint marks do not make up for other issues on your car you either have or you choose. Nothing IMHO looks sillier than a paint mark on a poor reproduction or incorrect part

[gt350hr]

  And CERTAINLY don't make letters  "carefully" , this was the assembly line , not penmanship class!

[CharlesTurner]

The 'KD' together may have indicated Knock-Down... but I have no proof of that.

The other K's I have seen on non-Shelby hi-po's.

The D alone might have had something to do with the DSO order?  We see DSO written on the rear axle housings on Shelby's.

[Bob Gaines]

The 'KD' together may have indicated Knock-Down... but I have no proof of that.

The other K's I have seen on non-Shelby hi-po's.

The D alone might have had something to do with the DSO order?  We see DSO written on the rear axle housings on Shelby's.

On 67 GT500's QD is commonly seen which leads one to believe that KD is not short for knock down. I am not sure what the D means but suspect Engine code and D is abbreviated DSO as you suspect?

[gt350hr]

  That makes the most sense to me . Knock down never worked for me.

[J_Speegle]

The 'KD' together may have indicated Knock-Down... but I have no proof of that.

KD is/was not for "knock down" That was sometime someone  put in a magazine article back in the 80's. Its been debunked for more than a decade.

Think the person found the letters and were trying to decode them while considering only one year and car but without the benefit of enough examples nor across other years. The two letters often are not even applied to the same area of the body and as Bob mentioned, in other applications QD, SD, KD, 6D ..... its easy to see (after looking at hundreds of examples) that they identified the engine and the D for what ever purpose and meaning it had. Also the engine code and the D are found remotely applied from one another also so it appears that though applied by the same person at the same time they had two different meanings in my opinion based on thousands seen. Maybe ten thousand by now

Like many things that make it into print it takes on its own life and gets repeated again and again

The D alone might have had something to do with the DSO order?  We see DSO written on the rear axle housings on Shelby's.

You will also see it applied to the taillight panel next to the second rotation number but the D on the forward panels is unrelated IMHO since it was applied to regular Mustangs, no exports and exports, 6 cylinders through 428 CJ's through the years of San Jose production in one or more locations. 40 years ago we thought it might be for disc brake but that didn't last for long once we had/found more examples

[Bob Gaines]

As a past furniture store owner KD is a furniture term meaning "knock down" commonly referring to ready to assembly items like tables ,chairs etc. It has been in the furniture vocabulary for over 50 years. I am sure someone in the past familiar with the term saw the markings on the Shelby cars and had a eureka moment  even though it was incorrect.

[shelbydoug]

As a past furniture store owner KD is a furniture term meaning "knock down" commonly referring to ready to assembly items like tables ,chairs etc. It has been in the furniture vocabulary for over 50 years. I am sure someone in the past familiar with the term saw the markings on the Shelby cars and had a eureka moment  even though it was incorrect.

I don't think furniture store owners should get blamed needlessly. It could have been a prize fighter/boxer and he was knocked down one too many times?

[J_Speegle]

If I recall correctly from the article the decoding first showed up in,  the person that made the conclusion was neither a prize fighter nor connected to the production or sales of furniture. Was repeated a couple of more times in print by the same person in decades gone by

The subject and debunking has been posted on this site a number of times - hopefully we can put this one behind us but it will never go completely away but we move on none the less

[shelbydoug]

To me, the D is just a curiosity just like the Z on the 67 Shelbys.

In this case the D seems to always be there, so that's the significance.

[Bob Gaines]

As a past furniture store owner KD is a furniture term meaning "knock down" commonly referring to ready to assembly items like tables ,chairs etc. It has been in the furniture vocabulary for over 50 years. I am sure someone in the past familiar with the term saw the markings on the Shelby cars and had a eureka moment  even though it was incorrect.

I don't think furniture store owners should get blamed needlessly. It could have been a prize fighter/boxer and he was knocked down one too many times?