Q: estimated cost of replacement of rear differential on 2002 Isuzu Rodeo

Rookie cbe0621eac06868b3efe0d8d1d3611e23c60d3114864ea2ec19a68cfbd3eebab
would appreciate closest auto repair shop too
(1) Answer
I don't know whether you have a 4x4 or not, or what your gear ratios are and it does make a difference.
The labor for installing a rear diff gearset assembly is about 3 to 4 hours at whatever rate ($85/hr?) in your locale, and the complete gearset assembly new is about $650 for a locking set, and about $450 for a non-locker. Myself, if it's 4X4 I'd use the locker, but if all you do is paved road and no snow, you could get by with the non-locker. I guess it snows in Ohio and you may be on some dirt roads, so I'd say go for the locker. A cheaper choice is to go for a guaranteed used complete rear axle or at least a guaranteed used gearset, but you have to be absolutely sure you have the gear ratio same as original, locker or not.
BTW, 'locker' means that one wheel won't spin freely and leave you stuck in a marginal traction condition; the diff 'locks' the rear wheels together once one wheel spins freely.
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