More Progress and Why all this Attention to Detail

Have gotten a bunch of parts reconditioned and ready to put back on the car.  Very rewarding in the end because this car will have nearly all of its original chassis fasteners reinstalled and looking like new, but it has been tedious at times. First goal has been to get the rear axle housing installed, so pieces relevant to getting that installed have taken precedence.  Plating the nuts that hold the differential housing to the axle housing and brake backing plates to the axle housing are finally about done.  Chose to plate those myself so that the rear axle can be installed while waiting for the other parts to be plated at the plating shop.

While doing this I noticed that the line assembly manual calls out cadmium plated nuts to hold the rear axle brake backing plates to the axle housing while those nuts that hold the front brake backing plates to the spindles are not specified about finish. So I pulled the original front and rear backing plate attaching nuts and noted that they DO look like they have different finishes.

The nuts on the left are from the rear axle, and clearly have residual cadmium plating, while the fronts (most of which were good enough to reuse as-is once cleaned) seem to be clear zinc plate.

Here's a picture of the newly plated differential housing nuts.

So after finishing up all of these nuts, I noticed that there are apparently 3 different versions of this 34445 nut.   One version has 6 raised dots (one on top of the nut at each shoulder designates grade 8, see nut at left), 3 dots( designates grade 5, middle), and a version without any dots(designates grade 2, right). The one without any dots was used on all 8 front spindle to backing plates.  I've seen these mixed on differential to axle housing attachment.  The no dot variety is also used on the rear axle housing to backing plates.

According to the parts catalog, this is also used to hold the rear axle rubber bumper to the bracket that attaches to the differential housing - it's specified as a 34445-S. 

 Interestingly, the assembly manual calls for a 34420-S8 or 55674-S8.  From Left to right below, 34445, 34420, and 55674.  Note that the 34420 (middle) came off of a 4F4 differential housing with 4F5 retainer and the 55764 came off of a  4E4 differential housing with 4D22 retainer.  So from sometime after May 4th 1964 (4E4) and sometime after June 5th, 1964 (4F5) two different nuts were used to attached the rubber bumper to the pinion snubber bracket.  The manual states that these two nuts were both an allowed fastener for this purpose.  All three of these are jamb nuts.

The nuts on the front spindles are identified simply as 34445 in the assembly manual, but as 34445-S in the January 1965 issue of the 1965 Ford Car Parts and Accessories Catalog.  The "-S" designation supposedly specifies the finish as "plain" but having pulled many of these off the car, it seems to mean either bare steel with cosmoline, dark phosphate and oil, clear zinc - so basically it seems that anything goes when comes to the finish.  It just seems that the assembly was done with the type of fastener that was in the bin at that stations on the line during that period of production.

So this may seem like an excessive amount of time spent on this, but the real reason for doing so is the value in being able to date and authenticate cars as this type of information is accumulated and documented. It's little things like the finish on certain nuts and bolts that can help to pinpoint time frames of when cars were assembled or whether they were built entirely, partially, or not built on the assembly line at all.  It's the accumulation of this and other data, and corroborating that evidence with a group of cars of the same time period coupled with hard documentation of other aspects (delivery time, purchase date, etc.) that allow us to piece the story together about a certain car or group of cars. 

So, why does it matter that some 34445 nuts are cadmium, other bare steel, others zinc.  Well it all has to do originally with the durability that Ford wanted (i.e. rust resistance).  Cadmium is used much less today and is a more costly process than say zinc chromates, but Ford may have decided that the rear axle nuts were going to see more splashing coming from the front tires that would be soaking these parts more than those on the front.  Maybe as production got more heated, they just started using whatever 34445 nuts that were on hand or maybe they simply had different parts in the bins for the front suspension assembly area on the line than those at the rear.  There is no way to be sure (yet!), but what we can be sure of is that this car had Cadmium plated 34445-S7 nuts used on the rear axle and zinc plated 34445 nuts used on the front.  So now, we can take that info and use it to compare and date other cars of the same period - and maybe a bigger story that we aren't even aware of yet will become clearer.