Gang,
I’m doing a little garage clean out. Somehow the Dayton show spurred me to inventory and clean up my parts storage.

A long while back I converted my ‘66 big cars to ‘70 discs in the front, everything from balljoint to balljoint. This means I now have a couple of spare ‘66 big car front drums which may still have enough meat to be used safely. And spare drum spindles and so on.

First I have a ‘66 98 which has 2.5” drums in the rear, anyone know how wide the fronts were? Could my ‘66 98 front drums be used in the rear?

Second I have a ‘66 Starfire which I think had 2” drums all around, so I have high hopes that I could reuse my front drums in the rear one day. Not that I want to, but as against selling them, I think I’m better off saving the parts.

Looking forward to your knowledge, views & experiences.

Chris

 

Fronts on all of the full size should be 11 x 2.75. Backs were 11 x 2.5 on the Ninety Eights and 11 x 2 on the Eighty Eights.

 

^^^ 100 % correct for 1965 - 1970 ^^^

N O Front will Ever work on a Rear , and
N O Rear will Ever work on a Front….

 

Craig & Joe
Many thanks for your attention and knowledge.

I’m sure you’re correct, but if you swapped the shoes and drums, what keeps front/back swapping from working?

And while I’m at it, any chance you’d have rear drums for a ‘66 Stafire or ‘66 98, given that my fronts won’t swap?

Cheers
Chris

 

The Fronts, as indicated above, are 11" x 2 3/4 " for both the 1965 - 1970 Oldsmobile 88 s & 98 s...
The Rears, as indicated above, are 11 " x 2 " for the 1965 - 1970 Oldsmobile 88 s.
The Rears, as indicated above, are 11 " x 2 1/2 " for the 1965 - 1969 Oldsmobile 98 s....

Since the sizes are Very, Very different, they Can NOT, Will NOT, and Do NOT Interchange.....

I have the Oldsmobile 88 --- 11 " x 2 " Rear Brake Drums --- Brand New....

At this moment in time, and quite possibly moving forward FOREVER, Absolutely N O. O N E has the 1965 - 1969 Oldsmobile 98 Rear Brake Drums.....

At this moment in time, I have *** N.O.S. *** Asbestos *** Brake Shoes *** for ALL three (3) of those applications!!!!

 

Chris, if your question is about using the front shoes along with the drums, the problem is the axle "stickout" (for lack of a better term) from the backing plate. The flange on the rear axle shaft that the drum fits over is offset from the backing plate by the width of the shoes. The 2.75" deep front drums will rub on the backing plate before the drum seats on the axle flange. What you are talking about is exactly what Olds did on the Vista Cruisers, where the back brakes are the same 9.5 x 2.5 as the front brakes. VCs use a unique dished backing plate that moves inboard by that extra 1/2" do avoid the drum bottoming problem.

You also need to keep in mind that when Olds engineered the brakes, they sized the wheel cylinders and brake shoes to provide the correct front/rear brake bias for the car. Going larger on the back brakes changes this and can cause premature rear wheel lockup under panic braking. Once the rear wheels are locked, there's nothing to prevent the rear end from passing the front (which is a clever way of saying you risk a spin).

 

Chris,
You wanted me to respond to your message, but it said " you don't receive messages ", so that apparently can't happen....

So, the EASY way is for you to " get me a message " or have me to respond to you, is simply :
Always best to simply call me --- 516 - 485 - 193five....

*** N.O.S. *** Asbestos *** Brake Shoes *** are Already " Unobtainim " , as the E P A and Asbestos Laws outlawed production in 1993 / 30 years ago....
I have already run out of many , many numbers / applications....

As far as my purchasing or swapping your USED HUB & DRUM Assemblies , two problems :
# 1 and most importantly ) I DO NOT do USED....... I D O Strictly, Strictly *** N E W *** &
# 2) You are in California and I am in New York --- you would need to Mike them ... see where they are between 11.000 " ( NEW ) and 11.090 " ( Discard ) ....
and ship them ultimately to their final destination --- someone who would need USED as opposed to nothing ... or for someone who would need a HUB ( they are USED world ONLY for many many
Years ) .....

I believe I have answered everything that you questioned... You have my phone number.... Craig.....