I've tried searching for GM part numbers using Google and can't find a resource. Does anyone know where I can lookup part numbers from a 68 AIM and cross reference them to parts I can order?

Example: there are two flashers for the 68 for directional and emergency lights. One on the top left of the fuse panel and the AIM references a primary p/n (3928799) and two optionals (3904868 & 3934200). There is also a flasher circuit forward of the center console, and also references a primary p/n (3866804) and an optional p/n (383636).

Zip only lists one flasher circuit - 12v. I'm not sure were this is to go (fuse panel or in the center console). I went to Advance Auto Parts, and the only flasher they carry is the LL552. The Advance Auto LL552 is about the same physical size as the center console circuit, where the circuit I bought from Zip looks like the one in the fuse panel. I'm surprised no one carries both, or references each other. I'm not even sure I have the correct circuits, so I'll install and see what happens, as my directionals decided to stop working the other day.

Any advice is totally welcome!

 

Yes and No.


The Illustrated Parts Catalogue is genuine Chevrolet. You may find original 68 part numbers. You are likely to find GM equivalent part numbers which would be functionally the same as the 68 part, but could vary in appearance or have a different manufacturer's part number on it. These would be GM service replacement parts which would have come into use after 1968.

I can understand the desire for original parts, but original parts are now 40 years old and may have gone out of production years ago.

If you want to continue the search for original parts, consider joining the NCRS and posting parts wanted ads in their Driveline magazine.
http://www.ncrs.org/

 

Thanks Mike. Im not looking for NCRS original parts - my mistake in how i worded my question. Im simply wanting to buy new parts to replace old parts that are no longer working, such as my directional circuits. In pulling the existing circuits, they looked physically different and the AIM references different part numbers for the two flasher circuits. What I'm trying to determine is, can I replace both existing circuits with two LL552, or do i need two different flasher circuits? The GM part number doesn't tell me what voltage or specs on the two, and is why I am trying to figure out what will do this job.

Thanks as always. I appreciate your consult!

 

I think way back when the 2 flashers were different because of the load difference between the turn sig and the hazards but the flashers today compensate for the difference.

edit - I use the Wagner 552 for both.

 

Thank you Roger!

 

I have found GM part numbers in the AIM to be a crapshoot. Sometimes they are still used today and sometimes not. Sometimes when they are still used today the current part is much like the original parts, and other times it is not.

Here is what I have done in the past to find out if there is a current GM part with same number as the original part. I put the part number into the GMpartsdirect.com database search and see if anything shows up. In your case, no hits on any of those part numbers.

Other websites that also use GM part numbers include Paragon and Rock Auto. Many Corvette parts suppliers intentionally leave out the GM part numbers - and I really don't blame them for this - to make it more difficult for you to source the part away from them. Many of the corvette parts suppliers go to a lot of trouble to round up parts from a variety of sources and make them available to us as "Corvette Parts." Some come from GM, Delco, but others are generic parts that they have researched and determine that they fit and do the job, so I don't fault them for not simply giving up all their sources of parts.

 

There is a functional difference in the aftermarket flashers, but it's not critical. The oe turn signal flasher was designed for a specific load which depended on the number of bulbs in the circuit. The reason for that was so that if a bulb burned out that side would not flash, a warning that a bulb was out. The manufacturers used this on most cars. If you hooked up a trailer you would have to change the flasher because with additional bulbs they would flash far too fast. Most flashers sold today are variable load flashers which will flash at the same rate regardless of how many bulbs (added or lost), so you lose the warning feature. I don't know if I know or ever knew what the design of the hazard flashers is. I think it's a variable load, but could have been specific to the higher load. Back in the day when you suspected a faulty flasher (and they were both easily accessible) you would swap them around to see if it cured your problem.

Steve

 

The only true way around this is to have all the history books to go with the assembly manuals. GM published part number history books every year that showed number changes and discontinued parts.

Then you'll also need a book collection of the parts books and old P&D (P&D = Parts and Distribution) price schedules. In the back of the P&D price schedules they listed the part number changes or if they were discontinued. It's not a easy task....

In our master books here, and in our computer system we have crossed many of the part numbers from years gone by.. But today most the numbers are all but long gone. Even after following a part number change through countless books you find out that the part was superseded by a number that is just a replacement functioning part and not anything you would use.

The assembly manual is probably best used as a reference when trying to find a part... Say you need an item on UPC 4: Sheet 2 item number 6. For us.. it's an easy way to reference back to a customer the exact item they are looking for. For us.. having the entire collection of Assembly manuals on our computers also makes it a quick task since the CD books have been OCR'd.

Willcox