Has anyone considered that maybe the Pinion Bearing pre-load has been set to high, and basically the roller bearings, and bearing races are just plain getting to hot, and inevitably burning up?
I had a 93 porsche 968 that had the problem crop up at around 29,000 miles on the odometer. It starts as a light whining sound at higher speeds, and as the bearing and race surface continue to deteriorate, the whining gets louder and his more noticeable at lower speeds. These cars had a Getrag 6 speed manual rear mounted transaxle tranny. A large percentage of the 968 Porches from production year 1992 through 1995 experienced this problem. It was definitely found via tranny break-downs in shops that the Pinion bearing pre-load was to tight, and just plain heated up the bearings and their race surfaces. You could actually see a carbonization of the roller bearins and races steel surfaces.......as a blackening or darkening in color. Getrag blew it right from the factory.
Porsche North America to this day has never reimbursed a single 968 owner who had to fork up out-of-pocket expenses ranging from $2,000. to $3,000 for tranny rebuilds with proper pinion pre-load.
Most of the trannsaxles failed just a few miles beyond the warranty period, or failed with low enough miles, but already had exceeded the 3 year warranty period.
These 968's were the poor man's Porsche, if you can call any Porsche a poor mans car. They retailed between $39k and $50k depending on what year and what options.
You expect some dealer or factory support when literally thousands of a Marque are experiencing troubles associated with manufacturing and not driver abuse. N. American Porsche snubbed all out of warranty owners.
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That whining in those Dana 44's sure makes me wonder, as whining usually is a tell-tale sign of something not getting enough lub and something having too, tight a tolerances.......
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It's a thought.
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