Lets look over your little woe is me list of problems. They resemble numerous threads on these very boards, with the SAME problem, different lubes. Funny I don't see anyone else blaming the oil that was in the vehicle at the time of failure???
1. Air filter. Easily could have been over oiled, just like other oil air filters. Negligence of previous owner. Oiled air filters,any brand, I think, should not be used on turbo charged engines.
2. 4500s are notorious for trash synchros that fail under normal use with factory oil. Mine has always worked flawless with Amsoil, yours didn't, bad luck for you, or driving habits?
3. Dana 80s need properly aligned for long life, this has been discussed in our magazine. That one, was obviously not. Mine at 150,000miles, 75,000 of that at 600HP sled pulling, and the ring and pinion look brand new. Amsoil since 35,000. But, maybe it will destroy it in the next 30,000, keep your fingers crossed Texas.
4. No idea about BMW bikes.
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