Snapper rear rider right hand differential same for all models??

[garyhalstead]

I need a used right hand differential assembly for a Snapper rear end rider . This is the larger of the differentials. I purchased my Spirit 140 Snapper in 1987. Its a 33" 12 hp. What I want to know is do all the old Snappers use the same differential? What year snappers can I look for that will have the same differential?