Parts for your 1987 Mitsubishi Pajero-Transmission filter

1987 Mitsubishi Pajero Transmission Filter: what’s fitted and how to look after it

On a 1987 Mitsubishi Pajero, a transmission filter is relevant for the automatic models only. Technical sources including the Mitsubishi Pajero/Montero Factory Service Manual (1983–1991, Automatic Transmission section), the Haynes Montero 1983–1993 manual, and Aisin-Warner service literature for the AW03-72 series confirm an internal, serviceable oil strainer (commonly sold as a “filter kit” with a pan gasket). Manual gearboxes on the same Pajero do not use a filter, they rely on gear oil and a magnetic drain plug.

For the auto, that internal strainer’s job is simple: keep clutch material and fine debris from circulating through the valve body and solenoids, so shifts stay crisp and hydraulic pressure stays healthy. Because it’s a metal-mesh style strainer, it’s more about flow protection than micro-filtration, but it’s vital for long transmission life—especially on vehicles that tow, see a lot of beach work, or slog through stop–start traffic in summer heat.

Best practice on a first‑gen Pajero is to service the auto trans on time and treat the strainer as a replace-or-clean item whenever the pan is off. A sensible rhythm is an ATF drain-and-fill every 40,000–60,000 km (sooner if you tow or work it hard), and a pan drop with strainer replacement around 80,000–100,000 km or if you notice shift flare, delayed engagement, or dark, burnt-smelling fluid. Mitsubishi specified Dexron II ATF back in the day, modern Dexron III/Mercon equivalents are typically used now—stick with a reputable brand and check the dipstick hot, engine idling, after cycling the gears.

• When doing the job: use a new pan gasket, clean the pan and magnets thoroughly, and fit the new strainer with fresh O-rings/seals.
• Torque the pan bolts evenly to light spec (don’t overdo it—warped pans seep).
• Expect a drain-and-fill to take roughly 2.5–4.5 litres, full capacity varies by variant, so top up by level, not a guess.
• Avoid aggressive “power flushes” on high‑km, unknown-history transmissions, staged drain-and-fills are kinder.
• Keep the cooler circuit clean and the throttle/kickdown cable adjusted—both affect shift quality and temperature.

If your ’87 Pajero is a manual, skip the filter talk—just change the correct spec gear oil on schedule and clean the magnet, and you’re sorted.

Popular questions

Does a 1987 Pajero manual gearbox have a transmission filter?
No. The manual uses gear oil and a magnetic drain plug to catch particles. Routine oil changes and magnet cleaning are the go, there’s no replaceable filter element in the casing.

How often should the auto transmission strainer be replaced?
For normal use, replace the strainer whenever the pan is off—typically every 80,000–100,000 km. If the ATF is dirty, there’s shift flare, or the pan shows heavy debris, do it sooner and consider shorter ATF intervals.

What ATF should be used, and how much does it take?
Use a quality Dexron II/III ATF that meets or exceeds the original spec. A simple drain-and-fill usually takes around 2.5–4.5 litres, while total capacity can be higher depending on the variant. Always set the final level using the dipstick procedure with the engine idling at operating temperature.