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==========================================1. Replaced just the brake shoes and tested at 50 to 60 mph where noticeable vibration occurred that wasn't there before the brake job.
2. This noticeable vibration was unrelated to braking events or to coasting downhill in neutral and was unrelated to road conditions.
3. All four wheels were previously balanced and originally put back in their original position after the initial repair as were the drums.
4. All six lug nuts on each wheel were torqued to 84 foot pounds using the classic star pattern. A thin coating of old (partially congealed) never-seize was applied to the rear hub to drum mating surface.
5. The main deviation from factory protocol was the common practice of adjusting the star wheel to the shortest position so that the drums go on easily and then lifting up on the emergency brake handle about a hundred times to adjust the parking brake to 7 clicks.
6. After an 18-mile test-drive loop, start to finish, to get to the highway and then to the first exit and back where half was highway and half were local roads, both drums "sizzled" a wet fingertip, perhaps the driver side drum more so than the passenger side drum.
7. The brake shoes had a gray pasty appearance, almost of leaking oil but no oil leaked on the brake shoes. ==========================================A. I rotated the tires front to back but they were balanced before so I don't see how that mattered afterward.
B. I very carefully torqued the six nuts on each wheel to 84 foot pounds, in a star pattern, with plenty of banging on the wheel assembly to jostle the seating position, although they were previously torqued to 84 foot pounds so I don't see how that mattered afterward.
C. I visually inspected the u-joints, wiggling them by hand, but I did not feel more than about a half millimeter or so of movement, but I don't know how much they're supposed to move - but they didn't change anyway.
D. I visually inspected the front and rear brakes, where no visual anomaly was seen, and wiped some of the never seize off, but it was a very thin layer anyway.
E. The only procedure I did very differently was that I explicitly followed the factory protocol for adjusting the brake shoes just prior to the drum replacement which was to mic the drum and mic the shoes and set the star adjustment to 1/2 mm (20 thousandths of an inch) smaller than the drum diameter.
F. I also left the parking brake adjustment loose at about 8 or 9 clicks instead of the 7 clicks (it still held the car on a hill but not as firm as did the first adjustment if the car was previously moving). ==========================================The procedure above "solved" the vibration problem.
The job is done but I would like to learn more about changing brake shoes. Do you have any idea what specifically had caused the vibration?