cost of front and rear differential service on 2007 Jeep Grand Cherokee

My dealership gave me an estimate for front and rear differential maintenance for $340.15. $90.95 of that was for labor and $207.89 was for PARTS. What parts could they mean. Isn't it just gear oil and labor?

Asked by for the 2007 Jeep Grand Cherokee
Your Jeep uses a synthetic gear lube that costs $30-40 a pint ( ouch ) each diff takes 2.5 pints, so that is about $100 per axle. If you don't use that gear oil, your diffs are history.