Humm....so many questions.....I will try to answer them all....
".....How are you dating that DUKW motor? You are putting a specific date on a specific motor... how? ...."
Hard work ...very hard work....
.....I have been a researcher of military vehicles for over 30 years and have done a great deal of research in the National Archives, Military History institute , Ford Motor Co. and other Archives.
In this research I have uncovered thousands of pages of documents and copied thousands more.
The documents I used to give the exact date are original GMC produced ones in the National Archives. The data on the DUKW motor comes from:
"MTER Record of Production Changes"
"GMC Truck and Coach Division "
"General Motors Corporation"
" Pontiac, Michigan, August 23, 1945.Each and every change made in production is recorded with Motor Number (if motor change) Chassis number and USA number (if vehicle change).
"....To be honest, unless you can relate DUKW production to CCKW production I think its best not to mingle the SN's and dates of one with another......"
I am not mingling SN's......I am talking only about motor numbers ...and motor changes in DUKW motors are done at the same time as CCKW and AFKW as all these motors were made at the same time and same motor production facility.
A change in one was a change in the other and the date for the DUKW changes prove out the date of the CCKW motor numbers listed in manuals such as the ORD 9 for the G-508. Motor numbers for DUKW's were not in a special number range nor did they start with # 1 for the first motor put in DUKW SN 001. ALL motors used in the CCKW and DUKW were made on the motor assembly plant lines at the same time. That means X amount of 270 motors were made on day Y....and these were used in CCKW production
and DUKW production.
Example of what I am saying here....the production figures I gave for April 1945....12,226 vehicles produced would equal 12,226 motors .....plus....you must add the DUKW production for that month of 600 vehicles (600 more motors) and it would equal 12,826 total motors produced for the assembly line. This does not take into account replacement motors made at the same time.
These motors all have numbers in the same number range with no differentiating between them and this is why motor numbers rose disproportionately to vehicle Chassis numbers.
This is also why if DUKW motor # 270-524701 was assembled on 10/15/44 then CCKW motor # 270-523270 would have been made 2 to 3 days earlier so it would be 10/13 or 10/12.
( using your figure of 12,000 vehicles/month = 12,000 motors divided by 21 working days average month = 570 motors a day ...524710 - 523270 = 1431 divided by 570 = 2.5 days)
Now...to this we must add the average of DUKW production for 1944 (11316 divided by 12 = 943 vehicles per month = 943 motors divided by 21 working days = 45 motors per day so our total motors (CCKW + DUKW) = 615 motors per day .....divide 1431 by 615 = 2.3 days.
Note that this is just the CCKW and DUKW motor production...I have not added motors for export, replacement motors or motors used in other vehicles such as AFKW/AFKWX which will reduce the days to about 2.
Now you can see why the DUKW motor numbers data is completely relevant to CCKW motor production and helps us to date CCKW motor numbers !
BTW...the motor number for the first DUKW.....#270-121725...........
"....I'm still not convinced that 12,000 CCKWs per month is not a valid average. ..."
It may be an average but it is not "tight" enough to use to date vehicles.
"....Even a fuel tanker is still a CCKW, but with a different body. Of the 1942 TM10's that list contracts and #'s of vehicles, they are ALL listed as CCKWs. Remember CCKW is not a truck, but a design specification...."
Oh,..OK..... I thought it was a GMC
model..ie 2-1/2 ton 6x6 CCKW......at least that's what my GMC master parts list says........
"....So tanker, cargo, tipper or 'None' they are ALL CCKWs....."
Yes, of course but....only to GMC...the Govt. (QMC/ORD) considered them as to what they were ...ie. cargo truck, fuel tanker truck, machine shop truck, Bomb service truck... etc. This is the way they are listed in the QMC/ORD reports
"...Remember 12,000 is the AVERAGE production per month. You really can't say that ONE month has MORE than the average, so the Average is wrong. That's NOT what an average number represents. And even if you totaled production by month you would have to have some significant deviations to affect an average of 40-50 numbers to get it to move significantly...."
Actually..if we are using this to determine how many of what or to date a vehicle......it does make a difference. Why not just use the actual figures? Why round it off or average it when we can use the correct monthly figures?
"....One HUGE problem with using the Sunderlin articles is that he rarely gave the source for his numbers. The MVPA should not allow historical articles to print without a bibliography..."
While I agree with you on the need to document the sources for data...I think the articles have enough information to be of great help with anyone with a GMC 6x6 truck..... would it be better to not have printed the articles at all? Bryce is a friend of mine and I think he did us all a favor by writing those articles.
"....Where exactly did he get NOV 44 for CCKW chassis number 394577 ?..."
Did he? Was it not Milspec that gave that date?
".....Math, estimates and conjuncture aside.. all we need are a few (3-5) data plates that show SN and DoD and that would put it to rest....."
Well...this is not the best to use to determine exactly a date as most CCKW's that exist do not have this info or ....on many, many it is wrong....... it is OK for "close enough".
"....Chassis number is 237321... typo...."
Right...I though so...my listing has your CCKW as 237321-
A1...which is not correct as it is actually 327321-
1...see what I mean about using existing numbers as "gospel"? They must always be verified to be sure they are correct.
".....Why do you believe that chassis and motor SN's would never match up? Jeeps do...."
Jeeps? Well ...yes and no!
Willys MB's do not have matching motor numbers and for the same reasons that GMC's do not...extra motors, generator sets add motor numbers to the mix.
Ford GP, GPW, GPA do have matching numbers (motor, chassis and data plate) because at Ford, the motor number was the vehicle VIN number. I should say...when a Ford motor was assembled and mated to a clutch and transmission it became a vehicle and was given a motor number.... the motor number was then stamped in the frame and data plate when it was assembled into a complete vehicle. Replacement motors did not have a GP/GPW/GPA motor number.
This was not the norm with other MFG's...Studebaker for example, used motors in the Weasel that did not match the MFG or ORD number.
".....They would have the same acceptance standards as CCKWs...."
This has nothing to do with the motor matching the chassis or vice versa. QMC/ORD contracts did not require the motor number to match the vehicle SN.
".....If we accept that 11/44 puts motor SN at 270-523270 then the Army was buying approx 2x the number of engines? At best I could see a 20% stock of new motors (and even that is a wild guess)... but as many an OD GMC 270 will attest, they were rebuilt at depot and put back in supply. I can't see a 4th Echelon shop taking more than a few days to turn a motor around...."
As I said earlier....the GMC motors were built for the CCKW, CCW, AFKW, DUKW and even the T-17E1 and T-17E2 Armored Cars (2 motors each!) by the same plant at the same time with no difference in motor numbers. To GMC a 270 motor was a 270 motor no matter what vehicle it was to go in. This is why the 270 motor numbers go higher than CCKW chassis numbers.
And....I am not sure that 270 motor production started at motor # 270-001......
"....... 'Late 44' for the introduction of the 6 valve fuel pump will suffice....."
OK, but I like the actual date....2nd week in October... better as it is more correct.
Oh...I almost forgot......the figures that I have quoted here for CCKW and DUKW production ....they are from:
"Summary Report of Acceptances, Tank-Automotive Material, 1940-1945 Army Service Forces, Office Chief of Ordnance - Detroit, Engineering - Manufacturing Division, Requirements and Progress Branch. (National Archives)
and......
"Statistical Work Sheets, Army Service Forces, Office Chief of Ordnance - Detroit, Engineering - Manufacturing Division, Requirements and Progress Branch. (National Archives) Jim Gilmore
Jim Thorpe, PA.