My car has a rumbling sound coming from either the transmission or the rear end. It feels like the gears are not meshing correctly, but every time I have it looked at by the dealership, nothing can be found wrong with it.
There can be multiple causes when dealing with a roaring or rumbling sound. A wheel bearing can cause a rumbling sound. When it comes to a rear end or differential it is important that all of the correct shims have been installed. Also that the backlash is set correctly. If the pinion has been torqued to the incorrect torque specification a similar issue can be the result. I would have this sound inspected by a certified mechanic, they will be able to diagnose your transmission issue and let you know what needs to be repaired.
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