Need help to ID spare tire lock bolt

[Gary B.]

Does anyone know the part number or application for the tire lock bolt shown in the attached photo? The overall length, from the tip of one end to the tip of the other end is approx. 8 9/16". The length of the threads is 4".

Thanks,

Gary


Tire Lock Bolt.jpg

[Joe L.]

Re: Need help to ID spare tire lock bolt

Does anyone know the part number or application for the tire lock bolt shown in the attached photo? The overall length, from the tip of one end to the tip of the other end is approx. 8 9/16". The length of the threads is 4".

Thanks,

Gary


[ATTACH=CONFIG]41818[/ATTACH]

Gary-----


It's a GM #471903 used for 1978-82 Corvettes.

[Gary B.]

Re: Need help to ID spare tire lock bolt

Joe,

The one in my photo can't be a 471903 because I have an NOS example of a 471903 in the GM packaging and the thread length on that one is 5". Overall tip to tip length of the 471903 and the mystery one in my photo are the same, however.

Gary

[Joe L.]

Re: Need help to ID spare tire lock bolt

Joe,

The one in my photo can't be a 471903 because I have an NOS example of a 471903 in the GM packaging and the thread length on that one is 5". Overall tip to tip length of the 471903 and the mystery one in my photo are the same, however.

Gary

Gary-----


Well then, it has to be a GM #345476. This was used from 1975-77. However, I have all of these bolts and I took a quick look at an NOS 345476 and the shank length looked longer and the thread length shorter to me than the one you pictured.

[Gary B.]

Re: Need help to ID spare tire lock bolt

Joe,

You've hit the nail on the head with what's confusing me. I think I some used examples of GM #345476 and the thread length on those is 3". So, there are bolts with thread length of 3", 4" and 5". I think the 3" thread length is 345476 and the 5" thread length is 471903. So, it the 4" thread length that has me stumped.

Gary

[Joe L.]

Re: Need help to ID spare tire lock bolt

Joe,

You've hit the nail on the head with what's confusing me. I think I some used examples of GM #345476 and the thread length on those is 3". So, there are bolts with thread length of 3", 4" and 5". I think the 3" thread length is 345476 and the 5" thread length is 471903. So, it the 4" thread length that has me stumped.

Gary

Gary-----


Here are photos of an NOS GM #345476. The overall length is 8-1/2" and the thread length is 3".

The GM #3933819 used from 1968-74 had an overall length of 7-1/2" and a thread length of 3". This same bolt was also SERVICE for 63-67 having replaced the GM #3841464 in January, 1971.

There were only 6 bolts that I am aware of that were used from 1963-82

VE63------GM #3794107 (uses free-spinning nut for thread stop)

E63-------GM #3833385 (uses welded-on nut for thread stop)

L63-67---GM #3841464 (uses integral thread stop) 7" overall length; 2-1/2" thread length

68-74---GM #3933819 (uses integral thread stop) 7-1/2" overall length; 3" thread length

75-77---GM #345476 (uses integral thread stop) 8-1/2" overall length; 3" thread length

78-82---GM #471903 (uses integral thread stop)

[Gary B.]

Re: Need help to ID spare tire lock bolt

Joe,

Wayne Midkiff has a posting from last year in which he says there was a 2nd lock bolt introduced in '65 for use with Goldline tires which was GM # 3872959, which is not on your list. Do you have any idea of the specs for GM # 3872959?

Gary

[David L.]

Re: Need help to ID spare tire lock bolt

Gary,

There is a GM drawing of the 3872959 bolt in the 1965 section of N. Adam's 63-67 restoration book, page 300.
8.00" changed to 7.50" on 11-6-64 as per the drawing.
5.00" plus thread length.

There are drawings of the 3794107, 3833385, and 3841464 bolts on page 109.

My early 63 SWC (VIN 1450) had the 3794107 bolt.

Dave

[Gary B.]

Re: Need help to ID spare tire lock bolt

David,

Thanks. So 3872959 is not the mystery one with the 4" thread length. I have to think we're still missing one.

Gary

[Joe L.]

Re: Need help to ID spare tire lock bolt

David,

Thanks. So 3872959 is not the mystery one with the 4" thread length. I have to think we're still missing one.

Gary

Gary-----


I don't think we're missing any. I think this is a GM #471903 which is what I originally thought. It's possible that the specs for it changed at some point.

[Gary B.]

Re: Need help to ID spare tire lock bolt

Joe,

I hadn't considered that the part would change without a resulting change in part number, given that there are so many different part numbers. I just assumed a change in design would be justification for a change in part number. But that is probably not always the case.

Gary

[Joe L.]

Re: Need help to ID spare tire lock bolt

Joe,

I hadn't considered that the part would change without a resulting change in part number, given that there are so many different part numbers. I just assumed a change in design would be justification for a change in part number. But that is probably not always the case.

Gary

Gary------


My experience has been this: sometimes the very slightest change results in a changed part number. Sometimes a substantial change is handled with a revision to an existing part number. I've never been able to figure out a "criteria" for this and I expect there either may not be a hard-and-fast criteria, it was subject to interpretation, or it changed over time.

[Gary B.]

Re: Need help to ID spare tire lock bolt

Joe,

I noticed today there's a used tire lock bolt on e-bay (item # 200827111836; I have nothing to do with that auction, nor do I know the seller) who thinks the 4" thread bolt is 345476. Whether that seller knows what he/she is talking about is unknown to me.

Gary

[Joe L.]

Re: Need help to ID spare tire lock bolt

Joe,

I noticed today there's a used tire lock bolt on e-bay (item # 200827111836; I have nothing to do with that auction, nor do I know the seller) who thinks the 4" thread bolt is 345476. Whether that seller knows what he/she is talking about is unknown to me.

Gary

Gary-----


Well, it's not the same as the 345476 that I posted a photo of and mine has a GM part number tag on it. As far as the one pictured on ebay all we know is what he says it is.

[Gary B.]

Re: Need help to ID spare tire lock bolt

Gary-----


Well, it's not the same as the 345476 that I posted a photo of and mine has a GM part number tag on it. As far as the one pictured on ebay all we know is what he says it is.

True. But the e-bay one is the same as mine, but the not the same as any other one with a GM tag on it. I was just pointing out the e-bay item as a timely coincidence.

Gary