front brake backing plates

[Brandon K.]

Can anyone give me the correct part numbers (ie those stamped on the back) of the front rotor backing plates for my 67? Cant seem to find that as a separate piece in the assembly manual.

Thanks, Brandon

[Terry M.]

Re: front brake backing plates

Brandon,

I think you will not find them in the AIM. Parts of the suspension were supplied to St. Louis as assemblies and I believe the spindles, bearings rotors and backing plates were an assembly. May have even included brake calipers, but I am less sure of that without looking at the AIM.

I am speaking for 1968 to 1972, so your 1967 might be a little different, but not by much. I think you will have to get someone to look for numbers from original car. Of course they might be the same part number that is in the parts book, but I am not sure even for my years.

Terry

[Joe L.]

Re: front brake backing plates

Brandon-----

Yes, you won't find these part numbers in an AIM since the front hub assemblies were delivered to St. Louis as a complete unit, of which the brake backing shields were a component thereof.

In any event, the 65-67 front left side shield was GM #3864117 and the front right side shield was GM #3864118.

[Joe L.]

Re: front brake backing plates

Terry-----

The part numbers which I provided in my previous post in response to Brandon were both the PRODUCTION and SERVICE part for 1965-67 Corvettes.

1968 and "first design" 1969 Corvettes used front backing shields GM #3898011, left side and GM #3898012, right side. The "second design" 1969 front backing plates were GM #3953423, left side and GM #3953424, right side. These backing shields were used in PRODUCTION until the end of the C3 era. Also, these shields were available in SERVICE from 1969 until they were discontinued several years ago. They replaced the "first design" shields for SERVICE when those parts were discontinued in the very early seventies.

How did the first and second designs differ? I'd like to know that, myself.

[Terry M.]

Re: front brake backing plates (more Joe)

Joe,

Thanks for the heads up - I knew you would know the numbers. Looks like we are both "working" the board at the same time. No I don't know the difference between the first design and later backing plates. I try to avoid much chassis judging - my girlish figure inhibits my performance down there. I do my best work with cars on a lift, but we seldom have that luxury on the judging field.

BTW: I have had two chances to check low mileage cars (a 1971 & 1972) for the method of manufacture of the backing plates per one of your previous questions. Inconclusive so far, as to whether they were formed from plated/galvanized sheet and sheered leaving edges to rust; or plated after forming leaving edges plated. Hard to evaluate with the wheels on the car. The 1971 will have wheels off soon so I may have at least a one car answer for you before the summer.

After checking these two I am leaning to the plating before forming theory you espouse. Now what about those gray/white washer tubes? :-)

Terry

[Joe L.]

Re: front brake backing plates (more Joe)

Terry----

With respect to the backing plate finish, I don't know that ANY of the front shields were manufactured from pre-punch galvanize material; mine certainly weren't. They were irridite dipped, zinc plate. It's only the REARS that I believe were pre-punch galvanize material. I don't know if they ALL were. But, I am ABSOLUTELY CERTAIN that at least one was: mine! My plater, who is VERY experienced and knowledgeable, pointed out the characteristics when he first gazed upon the pieces that I was taking to him for re-plating. The whole issue became crystal clear to me at that point.

[Terry M.]

Re: front brake backing plates (more Joe)

Well I figured so long as I was looking at the backs I should look at the fronts. NO? I am keeping my mind open to all possibilities.

And after looking at these two cars I am not so sure for either end. We do need a sample larger than 2 or 3 cars - so I am hoping others with low mile original cars will look too. Note to all: The size of the engine doesn't matter. :-)

The 1972 was at the Florida Regional where the Stinger folks were kind enough to loan us the use of one of their lifts for judging school for 2 days. That did not allow for removal of the wheels on the 1800 mile 1972 we had there. Still was fun though. Lots to learn under those conditions. Even had some nice mid-year and solid axel cars to look at - oops rubber bumpers too.

BTW: John Woods tells us they will be at Bowling Green with more lifts for Bow Tie judging. I am not 100% sure that is a done deal yet, but I understand the offer has been made. We might have to use them just for the judging school again, we will be working that out. In either case it will present some very nice opportunities to see some details we don't usually get a chance to see.

I have access to an 8600 mile 1971 that I will check as the shop gets the wheels off. It is being cleaned for Bow Tie. And before you all have the big one - I am watching the work closely - the car is in good hands even without my hawking on them. I would trust this pace with my own car.

Terry

[Jeffrey S.]

Re: front brake backing plates (more Joe)

Brandon: My '69 has the original backing plates, front and rear and I would be happy to go to where it is stored tomorrow afternoon and crawl under and get the part number for you. They are nice and clean and as long as the number is on the back side I think I can get it for you. It also gives me an excuse to peel back the cover and think spring. Jeff

[Brandon K.]

Re: front brake backing plates (more Joe)

Thanks Jeff..... I certainly appreciate the offer, however I believe I have gotten the information that I need. In any case, please dont let me deter you from uncovering your baby and taking her out for some fun.

Thanks again Brandon

[Jeffrey S.]

Re: front brake backing plates (more Joe)

Brandon:

I'm glad you got the info you need. I will post the numbers I found anyway since Terry indicated that a larger smaple would be helpful. Left=#3953423-L: right=#3953424-R

Jeff