I searched for this on the board archives but what I found confused me a little bit. I just want to know if I can pull the front aluminum drums off a car and put them on the rear of my car without any modifications. Also which years would fit it the swap would work.
The rear alum drums you need for the rear are the '78+ pieces often found on early 80's G bodys, some light duty big cars, some '82-87 Firebirds & Camaro's, some S10's. Just have to ck them all. Been pulling thick versions since the late 80's. Swapping from cast iron to an alum pair will remove 8.5-9 lbs of rotating mass from the r/e. Problem today is the same as it always has been, have to find ones that still have some meat in them The '68-70 aluminum GS- Skywagon front drums are a total different animal. Different size & wider. Search for & buy the alum fronts as well, & now have a pair on one of my Pontiacs, & another pair for another project. To install in place of regular cast iron front drums, will have to swap out the backing plates. Good luck. :3gears: Roger
The bare drum brake spindles for alum drums are not different from cast '67-72 drum brake spindles used with cast iron drums. As the '68-70 Buick alum front drums are wider & mate up to a wider brake shoe, the backing plates are stamped differently, have a wider offset, per say. In the course of removing early GTO & later "GS" alum drums from spindles I've actually destroyed quite a few of the alum drum backing plates Often, the only way to get "frozen" alum drums off intact is to cut the hardware & get it to release the drum. OEM spindle differences for '64-72 GM A-bodys: '64-66 DRUM spindle... has smaller diam holes where the steering arm attachs. '67-72 DRUM spindle: has slightly larger diam holes where steering arm attachs.Of course, mtg bolts are larger diam as well. '67-72 DISC spindle, has upper mtg boss milled down, drilled deeper & tapped differently for larger diam bolt to attach the top of caliper mtg bracket. A-body steering arms over the years also changed design at least 3 times, with the '71-72 versions being the beefiest. I try & maintain a good stock of all versions of straight unchewed used spindles. Several times a year, we will do a disc spindle machining run. The last two runs, we even made a dozen '64-66 spindles into disc spindles, so '64-66 owners could use their stock steering arms. Whatever makes it easiast for my customers. Hope this helps. :3gears: Roger
