Parts for your 1989 Mitsubishi Pajero-Transmission filter

1989 Mitsubishi Pajero transmission filter: what’s fitted and how to look after it

On a 1989 Mitsubishi Pajero, whether a transmission filter is relevant comes down to the gearbox. Technical references including the Mitsubishi Pajero/Montero Factory Service Manual (late-1980s), the Aisin-Warner 03-72 series/V4AW2 overhaul literature, and the Haynes Pajero/Montero Repair Manual for 1983–1996 all show that the four-speed automatic used in many ’89 Pajeros has a pan-mounted oil strainer (often called a transmission filter). By contrast, the manual gearboxes fitted to the same model year don’t use a transmission filter at all, they rely on gear oil and magnetic drain plugs rather than a replaceable or cleanable filter element.

For Pajeros fitted with the four-speed auto (commonly known under Mitsubishi’s V4AW2 designation, an Aisin-Warner 03-72 family unit), the transmission “filter” is an internal metal-mesh strainer that sits above the sump pan. Its job is to trap clutch material, varnish flakes and fine debris so they don’t circulate through the valve body and solenoids, helping the transmission shift cleanly and last longer. It’s not an external spin-on filter, access is via removing the pan.

As part of routine servicing, it’s smart to combine an ATF change with pan removal and strainer attention. In Aussie and Kiwi conditions, many workshops aim to inspect/clean or replace the strainer roughly every 40,000–60,000 kilometres, or sooner if the fluid smells burnt, looks dark, or shifting gets a bit lazy. Always use the ATF specified in the owner’s handbook for the exact variant, on these late-’80s autos it’s commonly a Dexron II/III spec, but checking the book beats guessing.

A typical service goes like this: drain the ATF, drop the pan, clean the magnets, and remove the strainer. If the mesh is clean and undamaged, it can often be washed and re-fitted with a fresh O-ring, if it’s torn, clogged or varnished, replacement is the go. Refit the pan with a new gasket, torque the bolts to the workshop spec, refill with the correct ATF, and set the fluid level following the manual’s hot/neutral procedure. After a short road test, recheck for leaks and confirm the fluid level again.

If the vehicle has a manual gearbox, a transmission filter isn’t used. Servicing focuses on the correct grade of gear oil and periodic changes, with magnet inspection during oil changes to catch any abnormal wear early.

• Watch for signs of a restricted strainer: delayed engagement, flare between gears, shudder on take-off, or a whine after hard work or towing.
• Good parts practice: new pan gasket, strainer O-ring, and careful cleaning of mating surfaces.

Popular questions

Does a 1989 Pajero have a transmission filter?
Yes, if it’s an automatic. The four-speed auto used in many 1989 Pajeros has an internal pan-mounted strainer shown in the Mitsubishi factory manual and Aisin-Warner service literature. Manual gearboxes don’t use a transmission filter.

How often should the transmission filter be serviced on an ’89 Pajero?
Many local workshops service the strainer every 40,000–60,000 km, or sooner if the ATF is discoloured or there are shift issues. The factory texts treat the strainer as an inspection/overhaul item, so following local conditions and fluid condition is sensible.

What ATF should be used after servicing?
Use the fluid specified in the owner’s manual for the exact transmission, for these late-’80s units it’s commonly a Dexron II/III-type ATF. A pan drop only replaces part of the total capacity, so follow the manual’s procedure to set the level hot and recheck after a short drive.