When it comes to replacing a pinion bearing, the cost can vary depending on the make and model of your vehicle. Generally speaking, you can expect to pay anywhere from $100 to $1,000 for the parts and labor required. The cost also depends on whether or not you're having an independent mechanic or dealership do the work for you. If you have an older car that hasn't been serviced in some time, then additional parts may be needed which will drive up the total bill even further. It's important to note that if there is damage done by another part such as a driveshaft U-joint, then these too must be replaced along with the pinion bearing. This could mean additional costs ranging into hundreds of dollars more than just replacing just a single part alone. So when looking into replacing your pinion bearing it’s best practice to get a full diagnosis before committing yourself financially - otherwise unexpected surprises may await!