Genuine BMW 325i Differential Seal

BMW 325i Differential Seal Parts Questions & Answers

• Shaft Seal With Lock Ring
  33-10-7-505-604
  Q: How to remove and install the differential pinion flange and oil seal?

  A: This procedure applies to both the front (AWD models) and rear differential. Removal: Remove the driveshaft and the exhaust system. Remove the retaining plate and make alignment marks between the driveshaft flange nut, the differential pinion flange, and pinion. Discard the retaining plate; a new one must be used during installation. Hold the differential pinion flange stationary by bolting a length of metal bar to it. Unscrew the nut, noting the exact number of turns necessary to remove it. Using a suitable puller, draw the differential pinion flange from the pinion and remove the dust cover. If the dust cover shows signs of wear, replace it. Pry the oil seal from the differential case with a screwdriver. Wipe the oil-seal seating surface clean. Installation: Smear a little differential oil on the sealing lip of the new oil seal, then press it squarely into the differential case until it is flush with the outer face. If necessary, tap the seal into position using a metal tube that only bears on its hard outer edge. Install the dust cover and place the differential pinion flange on the pinion, aligning the marks made during removal. Replace the flange nut, screwing it on by the exact number of turns counted during removal, so that all alignment marks align. Caution: Do not overtighten the flange nut. If the nut is overtightened, the collapsible spacer behind the flange will be deformed, requiring its replacement. This is a complex operation that requires the rear differential to be disassembled. Secure the nut in position with the new retaining plate, tapping it squarely into position.