[changzuki]

Details - Exhibit 2: Wheel Bearings, U-Joints, transmission, differential. and brakes.
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Most newer cars don't have the "adjustability" of the older ones. They are generally less maintenance and when the part goes bad, you toss it instead of rebuilding it.
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The front wheel bearings on Centurion are the standard tapered roller design. Prior to the Green Grand Prix they were repacked with moly grease and adjusted so they spun easily! The rear wheel bearings are pressed in, so they were greased and checked for ease of rotation - and that's where the fun began! There was some resistance when spinning the rear wheels so a little investigation by process of elimination took place.
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With an independent rear suspension like Centurion's, it's not too hard to disconnect each rear axle and the driveshaft. In doing so, it's easy to test each side independently from the differential and transmission to narrow down any issues.


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The bulk of the resistance was ultimately coming from the axle u-joints. This was really evident when simulating the actual ride height - which for the Green Grand Prix made Centurion look like it had a sagging rear.
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This sag was an intentional lowering via the rear buggy spring.
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The lowering was a preventive measure against a chance of the rear "jacking" on the track.
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The u-joints were correctly installed "tight" with no play at the caps, but the resistance felt by them as they would speed up during their angular momentum (due to the negative camber by lowering the rear) was a bit too much for my liking. So, out came the u-joint adjuster (ball peen hammer) and the yolks got a little corrective slap. Not hard but time consuming, now everything felt good.... Well almost...
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By hand, both the rear differential and the transmission turned like they had cold honey in them... And with snow still on the ground at the time that made sense. But if it were cold the morning of the Green Grand Prix Stage I fuel economy run, this simply would not do... So, after careful consideration (throwing all caution to the wind), both units were run at minimal levels and on automatic transmission fluid. At first this was against my better judgement, but they both turned so free-n-easy it was impossible to say no, plus time was running short and that's all I had in immediate stock on the shelf.. Without any apparent damage, both the tranny and differential performed: The trip down - Stage I on the track - And the trip home.
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Centurion's front disc brakes are the stock 1966 Spitfire issue and they dragged a little too much as well.
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After 3 million compression cycles with a clamp I decided the calipers were just fine and set my focus to the pads / pins. Using some small spring steel from who knows what, I made a couple of spring-type wedges to push the pads away from each other and free up the front rotors. What a difference a little drag makes!
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The downside was there was a bit more travel in the pedal before the calipers were able to fill up and engage the pads to the rotors. Small price to pay though.
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The rear brakes were another story. Being shoes-n-drums meant there was an adjuster someplace back there to make sure they would fully retract and not rub the drums. But even after adjusting, they still dragged a little so out came the file and the shoes got a little shave where the rear cylinders contact them. That took awhile but the piece of mind was worth it! And the list will go on.....
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~CrazyJerry