Parts for your 1998 Nissan Navara-Oil seals

1998 Nissan Navara oil-seals — what they do and when to sort them

Yes, oil-seals are absolutely relevant and used on the 1998 Nissan Navara (D22). Technical documentation such as the Nissan D22 Factory Service Manual (1997–2004, sections EM – Engine Mechanical, CL – Clutch, TF – Transfer, and DLN – Differential & Final Drive), the Nissan FAST parts catalogue, and common aftermarket repair manuals specify multiple oil-seals across the engine, gearbox, transfer case and diffs for KA24E petrol and TD27/QD32 diesel variants. So if this ute is leaving little spots on the driveway, those seals are right in the frame.

The job of oil-seals is straightforward: keep lubricants in and muck out. On a 1998 Navara they prevent engine oil, gearbox and diff oil from sneaking past rotating shafts. That keeps bearings, gears and seals happy, protects clutches and brakes from contamination, and helps the ute run reliably across big kilometres.

• Engine seals: front crank seal, rear main seal, and camshaft seals (engine-dependent).
• Transmission/transfer: gearbox input/output shaft seals, transfer case front/rear output seals.
• Diffs and axles: pinion seals, side/axle seals, front hub seals on live-axle setups.

Common signs they’re on the way out include: fresh oil mist behind the crank pulley, drips from the bellhousing (rear main), wet diff noses (pinion), oil tracking onto backing plates or inside rims (axle seals), low fluid levels, and oil smells on hot exhaust. Left ignored, leaks can glaze a clutch, soften suspension bushes, or starve bearings.

There’s no strict change interval, but smart servicing on a ’98 Navara means inspecting seals and breathers at each 10,000–15,000 km service, topping up/renewing fluids on schedule, and replacing any seal once wetness progresses to seepage. It’s cost-effective to fit a rear main seal during a clutch job, and to renew front crank/cam seals when the front cover and pulley are already off.

Quality matters: go genuine or reputable OEM, lightly oil the seal lip, and install square with the correct driver. Check crankcase and differential breathers—blocked breathers build pressure and force leaks even past new seals. For diffs, pinion seal replacement needs correct preload on the bearings, that’s a workshop task. Axle seals are moderate DIY with the right pullers and a torque wrench. After any seal job, refill with the proper spec oil and recheck for weeps after a few short drives.

Give the Navara’s underbody a quick look whenever it’s on stands—catching a tiny weep early saves a lot of mess and money down the track.

Popular questions about 1998 Nissan Navara oil-seals

Which oil-seals most often leak on a 1998 Navara?
Owners most often see the rear main seal, front crank seal, diff pinion seals and axle side seals start to seep with age. Gearbox and transfer output seals can also mist, especially if the ute has done a lot of towing or off-roading. Regular checks of the bellhousing area and diff noses usually catch the early signs.

Can these oil-seals be replaced at home?
Some, yes. Axle seals and certain output seals are achievable for a confident DIYer with pullers, seal drivers and a torque wrench. Rear main seals and diff pinion seals are more technical—clutch removal is needed for the rear main, and the pinion needs correct bearing preload. Many owners leave these to a trusted workshop.

What does replacement typically cost in AU/NZ?
Prices vary with labour and engine/drive configuration. As a ballpark, an axle seal might run a few hundred dollars, a rear main seal commonly lands in the mid-to-high hundreds once the gearbox/clutch work is included. Pinion seals can be similar due to setup time. Quality seals are inexpensive, most of the bill is labour.