63 Half Shaft U-joint Flange

[Carl S.]

I have two different u-joint flanges on my half shafts. One is 5/16" thick where the bolts pass through to connect to the spindle flange and the other is 7/16" thick. The thinner of the two apears to be original and has part of a part number on it but I can only identify 3 numbers. I would like to identify the correct flange so I can get a set that matches. On another subject I need help on the finish for the lock nuts holding the steering knuckle to the front spindal. I got a set of bolts and nuts from Dr R that are not correct for a 63 the bolts are both the same length. The lock nuts are cad plated, is this correct? The ones I removed are black phosphate on the underside of the nuts the rest was just rust. Thanks in advance for aney information. I just got my break cylinders and master cylinders back from White Post Restorations they did a great job I shiped them last friday and got them back this friday. So I thank the person that recomended them.
Carl

[Joe L.]

Re: 63 Half Shaft U-joint Flange

Carl-----

The u-joint flange with the THICKER cross section is the correct one for a 1963. This was a one-year-only item and was of GM #3832048 and was discontinued in March, 1966 and replaced by the 64-74 flange, GM #3843018. The latter or its replacement, GM #360913, is likely the thinner flange that you have. The 3832048 was not as strong as the later parts; it was a cast nodular iron piece whereas the later were forged. The 3832048 is also very hard to find these days.

Most of the Corvette front steering arm-to-spindle bolts were black oxide or black phosphate finished. However, the zinc plated ones that you have are much more durable as to finish and prevent exactly the sort of rust problems that you experienced. What's more, except for any exposed threads on the inner end, you can't see any part of the bolt once it's installed. If you wish, paint these exposed threads with Quanta's black oxide paint and no one will ever know the difference. The nuts used on these bolts were zinc plated, stover-type locking nuts.

[steve principle]

Re: 63 Half Shaft U-joint Flange

I think 64 is the same and I need the spindel bolts too.
What are the lenths?

[Michael H.]

Re: 63 Half Shaft U-joint Flange

Carl,

I'm not familiar with the reproduction steering knuckle bolts but I would be sure they are of good quality before using them. If I remember correctly, the originals were grade eight. (six radial lines on the head) This is not a good place for a poor quality bolt.

The original nuts for 63-64 spindle were not zinc or cad plated but had a dark colored plating. They were non crimped top style locking nuts, different than the crimp top prevailing torque style used in later years.

As far as color for the plating, it really isn't critical as the entire knuckle assembly, including the backing plate, drum, bolts and nuts, was painted black before the assy was installed on the chassis.

Michael

[Joe L.]

Re: 63 Half Shaft U-joint Flange

Steve-----

Yes, as far as the bolts go, the 64 is the same as 63. The bolts were as follows:

long---7/16"-20 X 2-15/16" (use 3")

short--7/16"-20 X 1-31/32" (use 2")

The above were special bolts with non-standard shank length for their overall length. However, you can use standard bolts of GM-300M material (SAE grade .

[Joe L.]

Re: 63 Half Shaft U-joint Flange

Michael----

The only 2 style lock nuts that I've ever seen used on any high strength application on a 60s or 70s GM car are the Stover-style or the "3 external stake" style. The Stover style are also referred to as "elliptically offset stop nut" (since Stover is a trademark owned by Russell, Birdsall, and Ward). This style nut was used on early small block rocker nuts and also most big block rocker nuts (GM #3896648). As far as I know, this is the style nut that was used on the 63-67 steering arm attachment point. I'm certain that the "3 external stake" style nut was not used and, as I say, that's the only other style locknut that I've ever seen used on a GM high strength application (GM 301M/SAE grade . I believe that the nut used for the 63-67 front steering arm attachment was GM #3832788. This is a Stover-type nut of GM 301M material. It is very similar, if not identical to nut GM #9422300.

GM #9422300 has a zinc plated finish. I don't know, for sure, what finish that the 3832788 had, but I strongly suspect that it was zinc or cadmium, too. It's possible that it could have been black zinc, though.

The 68-82 Corvette applications used 1/2"-20 bolts. These bolts were black oxide or black phosphate finished. The nuts used were GM #9422302 which were Stover-type nuts that were zinc plated.

[Michael H.]

Re: 63 Half Shaft U-joint Flange

Joe,

I have a bag of correct NOS original 63-64 spindle bolts and nuts somewhere in the garage. (all are black) I'll try to find them and scan. One of the nut styles that GM used had a punch in the side for it's self locking feature instead of the crimp top that you describe. If I remember correctly, the crimp style didn't start to show up for this application until 65.

I have several bags of original GM NOS lock nuts and many are a different style even tho they are the same part number. I assumed that GM was using different suppliers and styles for the same part number.

[Joe L.]

Re: 63 Half Shaft U-joint Flange

Michael-----

Yes, I have seen different style lock nuts of the same part number. I don't know how this happens as the I would think that the drawing for the part would be specific as to the type of lock nut. One example are the small block rocker arm lock nuts. This nut, GM #3744341, was used in both the Stover nut style and the "3 external stake" style. Earlier ones (in the 50s and 60s) were usually the Stover style. Later, they were usually the "3 external stake" style.

I am familiar with the "punch-in-the-side" or GM "N" style locknuts. However, all of the ones of these that I am familiar with are GM 286M (SAE grade 5) material. I'd be surprised if a 286M nut was used on a high strength application. It's possible that some of this style nut was made to GM 301M specs, but not to my knowledge.

[Michael H.]

Re: 63 Half Shaft U-joint Flange

Joe,

I'll try to dig out more info on this for us this weekend, if possible. More company from the frozen north is making it difficult to be on the computer. Amazing how much more popular I am this time of year since I moved to Florida.

In the meantime, if anyone happens to have a 63 or 64 apart for restoration, we would like to have a description of the nuts/bolts that fasten the front spindle to the backing plate.

[Geoff C.]

Re: 63 Half Shaft U-joint Flange

I have found the error source in these hex cap screws: the problem is that we must rely on human beings. And human beings are capable of making errors with our inventory control system. Three parts numbers were moved and switched. We inventory 1,300 different part numbers for what I call hardware: nuts, bolts, screws, cotters, keys, washers, rivets, etc, etc, etc.

Regretfully, what was sent was not 7/16-20 by 3 and by 2.5 inches, and not grade 8. I discovered this in a visit to my warehouse today. (My first visit inside this year.) I placed two pieces of each size ready for shipping tomorrow.

Geoffrey Coenen

PS Since my wife feeds stray cats at our warehouse, I have only been there on Saturday and Sunday, and not gone inside until today. If you had emailed me I would have known sooner.

[Carl S.]

Re: 63 Half Shaft U-joint Flange

The right side hade the staked nuts and the left side had the Stover nuts on my 63 coup 09240 59K miles. The stover nuts that were on the left side are not the same style as what is curently sold. The flats were half the height of the nut and tapered inward to a circle till it reached the top, not like curent replacment nuts where the flates are 3/4 the heights with a dome on top. The oblong hole is the same in both old and new. I have the same problem with the rear, I have two different half shaft U- joint flanges. There is no apperent damage to either side of the car that would require replacment. The front and rear spindels, backing plates, durms, bolt head markings are all corect. Brake cylinder date codes are all precede the buld date. The rear trailing arms were equaly rusted away. These are the things that are driving me nuts during my restoration. As with alot of things the JG provides no help. My frame is finished and I am starting to install the front supension. I wish there was away to Just attach a photo, it would make it a lot easer to explane things. I have seen this explained in the past but still don't understand how it can be done.
Carl

[John H.]

Re: 63 Half Shaft U-joint Flange

"Optional Constructions" for fasteners (and for many other parts as well) were VERY common in the 60's, and were always shown on subsequent changes to the original drawing as secondary sources were given a piece of the business for a particular part, or because the primary supplier was already tooled up to produce a part a given way which deviated slightly from the original design, but had Engineering sign-off approval as an equivalent. My Production Engineering Group handled lots of these supplier requests for optional constructions or minor drawing changes to simplify tooling and processes or checking fixtures; they were a normal part of everyday business.