Re: 87 rear diff vibration

[Elcrinv@xxxxxxx]

It sounds more like a driveshaft problem. If you haven't replaced it you will 
need a new one. Drive line service of Portland (in Roundel every month) will 
swap your old one for a rebuilt for about $250. It comes complete. 
Replacement is pretty straightforward if you have a lift.
Of course this doesn't mean that you may also have a diff problem anyway. 
Lift up the rear wheels and put it in gear and listen to it by putting the 
blade of a large screwdriver against the diff casing and listening at the 
other end of the screwdriver. Don't do this alone and be very careful if you 
don't have the aforementioned lift. Better yet go to a shop and have them 
diagnose it.
Fred Callender RMC

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