LE bolt head 7/16 fine thread bolts

[Timothy B.]

Can anyone ID this headmark, I am curious if this bolt is hardware store bought or C2-C3 production. I seem to remember buying some at Carlisle a while back but not sure anymore..

These bolts attach the spindle to the halfshafts.

You can tell it's snowing in MD today..

[Rich P.]

Re: LE bolt head 7/16 fine thread bolts

Tim,

LE (Lake Erie I think it stands for) were not used on c-2 cars. The 1/2 shaft bolts I have seen most commonly would be O and M both grade 8. Most importantly the have a 3/8" or so shoulder, just enough so the shoulder woulf fit in the axle flange. Now this is the same length bolt and grade as the rear caliper mounting bolt (those have no shoulder and are threaded right to the head of the bolt) and sometimes were swapped BUT the design was to use the shoulderd bolt for the axle flange.

Rich

Yea it's snowin in PA too

[Timothy B.]

Re: LE bolt head 7/16 fine thread bolts

Rich,

So you are saying it's a typical C3 headmark bolt.

Thanks for the reminder about the shoulder on the bolt as it's important for the spindle/halfshaft and I forgot about that. These bolts do not have any shoulder and are 1 1/8" long so I assume they are for brake caliper.

[Wayne M.]

Re: LE bolt head 7/16 fine thread bolts

...The 1/2 shaft bolts I have seen most commonly would be O and M both grade 8. Most importantly the have a 3/8" or so shoulder, just enough so the shoulder woulf fit in the axle flange. ....

Rich -- are these the "O" marking ? Off a Jan '64 car. Also have about 1/4" unthreaded "shoulder" under the head.

Tim -- do you have these original style bolt locks ?

[Rich P.]

Re: LE bolt head 7/16 fine thread bolts

Rich,

So you are saying it's a typical C3 headmark bolt.

Thanks for the reminder about the shoulder on the bolt as it's important for the spindle/halfshaft and I forgot about that. These bolts do not have any shoulder and are 1 1/8" long so I assume they are for brake caliper.

Tim,

I think you could see the LE on mid 70's -up. threaded to the end would be calipe bolt.

Wayne,

Thats them, Starting in 69'ish the O could have a line in the middle and also a cross.

Rich.

[Alan D.]

Re: LE bolt head 7/16 fine thread bolts

Wayne,
My bolts are the same as shown however the French locks are a little different. (different vendor?)

The three shown are original (at least two are), did replace one wheel bearing back in 60's, but other side never touched until 2006.
These are from a Mar64 car.

[Timothy B.]

Re: LE bolt head 7/16 fine thread bolts

Wayne,

My car is a early 63 so there are no locks until sometime later in production. I don't believe there are any lock washers either for the early cars. I don't understand how the factory figured these bolts would stay in place. I would not want to be near the assembly if one let go.

I can't remember if I used locks or not but I will get a set of reproduction french locks and install them..

[Joe L.]

Re: LE bolt head 7/16 fine thread bolts

Rich,

So you are saying it's a typical C3 headmark bolt.

Thanks for the reminder about the shoulder on the bolt as it's important for the spindle/halfshaft and I forgot about that. These bolts do not have any shoulder and are 1 1/8" long so I assume they are for brake caliper.

Tim------


Not on any C3 I've ever noted. GM says that the same bolts were used for the half shaft flange-to-spindle flange for the L1963 through 1979 period. These were GM #3843384. They are 7/16-20 X 1-1/8" long. They have 1/8" of un-threaded shank below the head and 1" of thread. They are of GM 300-M material grade (SAE grade 8) and have a phosphate-organic finish. These are the bolts seen in Wayne's photos. This is the only style bolt I have ever seen on any 63-79 that I've observed. The only differences I've observed relate to the headmarking in the center of the bolt head---the rest of the head configuration is the same.

GM also says that the bolts used for the rear caliper-to-bracket mounting for all 1965 thru 1982 were exactly the same bolts, GM #3843384. The ones on my 1969 were originally of the exact same configuration as the half shaft bolts in all respects, including the 1/8" unthreaded shank. As a matter of fact, I don't understand why any different, all-thread bolts would have been used for this application. The unthreaded shank would be just as applicable here as for the half shaft bolts. Did some cars use all-thread bolts for the rear caliper mounting? It's possible; I have not looked at every car built in the 65-82 period. But, the 3843384 are the bolts that were supposed to have been used.

Was the GM #3843384 bolt ever available in SERVICE? Yes, it was, but only from early 1964 through January, 1965. At that time, it was replaced, for SERVICE, by the GM #454972. The latter is a standard-type bolt of 7/16-20 X 1-1/8" length, with 1/8" of unthreaded shank and 1" of thread. They are GM-300M material grade. The big difference with these bolts from the 3843384 is the fact that they would have a standard head configuration and likely the trimmed style (as seen in your photo of the "LE" bolt). Also, they were zinc plated rather than phosphate-organic.

After January, 1965 if one had gone to a Chevrolet dealer to obtain a bolt for either the half shaft or rear brake caliper, one would have been sold the 454972.

While the 454972 replaced the 3843384 for SERVICE in January, 1965, GM says that the 3843384 continued to be used in PRODUCTION for the applications previously described. That is also consistent with what I've observed. Is it possible that the 454972 was ever used alternately in PRODUCTION. Yes, I'd say it's possible. I've never observed a case of it, but it's possible. As I say, from what I can see of it, your bolt appears to me as I would expect a 454972 to appear. Of course, whether it had a PRODUCTION or SERVICE "heritage", we have no way of knowing.

[Joe L.]

Re: LE bolt head 7/16 fine thread bolts

Wayne,
My bolts are the same as shown however the French locks are a little different. (different vendor?)

The three shown are original (at least two are), did replace one wheel bearing back in 60's, but other side never touched until 2006.
These are from a Mar64 car.

Alan-----


These all look the same to me except that the outer ones have the locking tabs broken off (and, are thus useless).

These are the early style locks used from L1963- to sometime in 1964.

[Joe L.]

Re: LE bolt head 7/16 fine thread bolts

Wayne,

My car is a early 63 so there are no locks until sometime later in production. I don't believe there are any lock washers either for the early cars. I don't understand how the factory figured these bolts would stay in place. I would not want to be near the assembly if one let go.

I can't remember if I used locks or not but I will get a set of reproduction french locks and install them..

Tim------


One other thing that I should have mentioned but neglected to do so. It's especially pertinent in your case.

Most 1963's used bolt GM #454958 for the half shaft flange-to-spindle flange. This is a standard-type bolt but I have no information on it, at all. However, given the part number I would expect a standard, trimmed hex head (like the one pictured in your post), GM 300-M material grade, and zinc plated finish.

It MIGHT be a little shorter that the 3843384 or 454972 at, perhaps 1" or 1-1/16" in length and, at that length, is likely all-thread with no unthreaded shank.

So, I'd say it's POSSIBLE that the bolt you have pictured is an original configuration 1963 bolt. I can't say one way or the other, though.

[Timothy B.]

Re: LE bolt head 7/16 fine thread bolts

Thanks Joe, I appreciate the info.

I have one more bolt that I wanted to share. This one is left over from the 63 and it's 7/16 grade eight fine thread, TR headmarking and 1 3/16" long with NO shoulder.

The bolt looks old and I glassbeaded and blackened it but it's the only one I have. I can't think of another application on the car for this type of bolt.

The current reproduction bolt from Paragon is pictured on the car and I am almost sure it has a shoulder. I am going to do away with the lock washers and use the french locks.

[Joe L.]

Re: LE bolt head 7/16 fine thread bolts

Thanks Joe, I appreciate the info.

I have one more bolt that I wanted to share. This one is left over from the 63 and it's 7/16 grade eight fine thread, TR headmarking and 1 3/16" long with NO shoulder.

The bolt looks old and I glassbeaded and blackened it but it's the only one I have. I can't think of another application on the car for this type of bolt.

The current reproduction bolt from Paragon is pictured on the car and I am almost sure it has a shoulder. I am going to do away with the lock washers and use the french locks.

Tim-----


It's possible that this is a 454958. Its configuration is in the right "ballpark" and, as I mentioned, most of what I described it as is speculative.