This is more for the search engine than anything else, I'm spectin' it'll drop like a stone. Took the Axle out of the Hearse and over to a Driveline shop. There was a gear whine below about 30 mph. I put a coathanger in the filler tube and saw shavings and lept to conclusions. They took it apart and said they'd never seen anything like it, didn't even have the slightest clue how to disassemble the chunk. I called around, googled, tried everything. It seems that nobody knows about Cadillac's Controlled Diff. FWIW, the gears looked good, the bearings were fine, and there wasn't a lot of garbage in the bottom of the carrier, I suspect I scraped up the shavings from initial break-in. POR15'd it, bought new shocks, u-bolts, and had the schackle I cut out fixed, and threw it back in the car. 10 miles later, I discovered that old limited slip diffs don't LIKE synthetic....and synthetic doesn't LIKE GM Limited Slip Additive. I then discovered draining an axle with a 4 oz Mityvac sucks balls. I then discovered pushing 5 pints of fluid uphill back into the axle ALSO sucks balls. Then I discovered the blessed silence of a working axle...and that gearwhine doesn't seem all that bad in retrospect. :|
redline might make a syn diff lube that might work. However, synthetics seem to make them run louder. Did on my non-HAMB jeep.
Cadillac made those controled diffs from about 1962-1969 as a option. They figured with a full load of people or a casket 6000 pounds cranking down a freeway would need all the traction it could get. Most shops cant rebuild those rear ends because the ring is rivited to the carrier. If you need some parts I know of a guy who has some used diffs.
Thanks! I think we've determined the diff is in good condition, and the car doesn't see a lot of miles anyway (with 9 mpg and $4/gal gas), but I appreciate you're responding to such an old thread. I found an axle at a local cadillac only wrecking yard, but I hope I'll never need it.
The Jalopy Journal
