Pajero I have a 2002 NM Pajero (Montero) 3.2 l Diesel @ 275,000 Km. (171000 Miles). Should I change the timing chain as a precaution ?

1. Maruti Suzuki Ciaz SHVS Mileage - 28.09 kmpl
Tank capacity - 43 L
Range - 1208 km
Engine - Diesel SHVS, 1.3-litre, 90PS, 200 Nm, 5-speed Manual
2. Maruti Suzuki Celerio Mileage - 27.62 kmpl
Tank Capacity - 35 L
Range - 967 km
Engine - DDiS 125 Diesel, 0.8-litre, 47.60PS, 125 Nm, 5-speed Manual
3. Maruti Suzuki Baleno Mileage - 27.39 kmpl
Tank Capacity - 37 L
Range - 1013 km
Engine - 190 DDiS Diesel, 1.3-litre, 75PS, 190 Nm, 5-speed Manual
4. Honda Jazz Mileage - 27.30 kmpl
Tank Capacity - 40 L
Range - 1092 km
Engine - I-DTEC Diesel, 1.5-litre, 100PS, 200 Nm, 6-speed Manual
5. Tata Tiago Mileage - 27.28 kmpl
Tank Capacity - 35 L
Range - 955 km
Engine - RevoTorq 3-cylinder Diesel, 1.05-litre, 70PS, 140 Nm, 5-speed Manual

No idea why fixya keeps sending me questions about a 2002 Montero (Pajero). I have never owned one. I did own a 2005 Pajero diesel turbo but sold that in 2014 and now own a 2014 Triton.
Sorry I cant answer your question.
Ken

MITSUBISHI Pajero Montero Shogun 3 2 DI 160 HP 2006 Present
Torque 281 lb-ft @ 2000 RPM
381 Nm @ 2000 RPM

We have no information on this subject.

80/90 thousand miles or ten years if mileage is lower than this

I checked out the pajero forum, they don't mention the bottom tensioner as being the noise maker here but rather a sloppy chain, stretched beyond the tensioner and riding on the guides. The noise sounds like it comes from the fan area as a metallic chattering. They sell a chain that has a master link in it, and you don't have to tear down the entire engine again to get to it, just the top cover,, Cut the old chain, and use it to pull the new one through. Also, if your chain did jump its gear, it would only be a matter of 8 - 10 miles before the cam breaks. Hope this helps.

1984 years came with the 2.0L, 2.6L gasoline and 2.3 diesel engines.

It's most likely a timing belt, but read further for more info. Recommended to be replaced at 60,000 miles (96,000 km) on gasoline engines and on diesel engines at 50,000 miles (80,000 km).

The 2.0 L Engine have two timing belts. One connects the crankshaft and camshaft, the second one drives the right silent shaft.

The 2.6L engine has a timing chain and a silent shaft chain.

Please check to see which particular engine you have and refer to the above for your answer.

The first change/flush will usually be at 75,000-100,000 mi.

I got my book from ebay.com 
good luck  Grace