I thought about this NFS. It is possible, but should be unlikely.
Reason I say "should be", when they order parts for your car, they quote your chassis number to ensure parts compatability. Therefore, if your car is "stock" and has never had the ratios changed during previous transmission work, the differential they order for you will be a match for the gear set in the tranny.
It is still possible to get it wrong if they order from part numbers without checking the chassis code.
I was wondering in Ian's case if the garage fitted the diff, filled it with oil, and then left the filler plug loose? This would lose the oil. Was the plug in place Ian when the diff blew?
Or did they order a diff from an Impreza, which would be a lower ratio than the box? Hard to figure. If they ordered using part numbers from SubaruParts.com, it would be wrong, because the US market SVX's have a higher overall final gear ratio than the English ones. Then the box would not match the ratio of the diff.
Joe
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