Rear Axle Detailing

by George Nenadovich

 

Here is an 8.5" housing from a 72 Skylark.....already removed the axle assemblies, brake backing plates, carrier, pinion and bushings/bump stops.

 

This is a good degreaser and works well in a spray bottle.

 

Some basic hand tools to remove the heavy grime/grease/tar and undercoating.

 

Here is the housing cleaned......use a putty knife/chisels/scrapers to remove heavy grime. Next, use degreaser and steel brushes to degrease unit. I use a 1500 psi pressure washer for the final cleaning...this allows you to access all areas and does an excellent job of also removing loose scale/rust.

 

Here is the factory axle code stamped on the pass side axle tube about 4-6" from where the axle tube enters the center section .... LK B157 2

This means LK, gear code for 2.56 gear w/no posi. B is for Buick and 157 is the 157th day of the year. 2 indicates 1972

 

Axle center housing cleaned and clearly shows factory paint mark...in center....a light pink color.

 

A is cast into the center section for A-body models. Also note axle code is about 4" from the center section. On some rear axles...the axle code can be hard to read due to corrosion or light stamping from the factory. Center section still has a lil undercoating on it and this is easily removed with lacquer thinner. Notice the center section was not painted but a bare cast metal....some discussions on forums have been about the center setion being painted all black like the axle tubes or left cast iron gray......I have done over 20 of the 8.5" rears and 10 Chevy and Olds 12 bolt rears...none of them had the center section painted black.

 

Nice picture showing the 2 plugs welds for each axle tube indication of the 8.5" rear axle. The 8.2" rear axles only have 1 plug weld on each side.

 

 

Here are some local paints you can purchase to paint the rear axle.

 

Rear drum brake parts bead blasted and painted black.

 

Rear axle shaft with bearing, seal and crush sleeve removed....this axle is going to the axle rebuilder for all new bearings, seals, crush sleeves, installation of 3.42 gears with a posi unit.

 

Good idea to use a 7/16-20 die to clean all wheel studs before bead blasting and painting.

 

Make a cardboard mask......use a 4" diameter circle template to make your cut-out...just happens the empty roll of MIG welding wire is 4" diameter.

 

Here is the rear hanging from an oak tree with the center section painted cast iron gray and clear coated. Axle tubes primed with dark gray primer.

 

If you don't have a large tree to use, you can hang the rear from some sawhorses.

 

Center section edge masked off with 1" masking tape.

 

Cardboard mask in place in order to paint axle tubes. Notice hole in axle tube...this is for the plastic axle tube vent which will be replaced by a new one.

 

Completed axle housing ready for the rebuilder.

 

 

All new brake hardware installed....the kits are cheap and a good idea to replace 37+ year old brake hardware. Also, good time to install new brake shoes, wheel cylinders, bushings, brake lines and rubber hose.

 

Completed rear installed in the car......just need to add a new cover gasket and rear gear oil.