i was going thru this post & saw people complaining the Pajero " HEAT-UP " problem.
Actually most new people i also meet say that to me, that Pajero has heating problems.
The thing is, Pajero is a purely TAILORED Vehicle.
means: company prescribed tyre size, oil, exhaust system & misc. good quality drivetrain parts.
You need all things to be working in perfect systematic-function to get the BEST Mpg + Overall enjoyment 
Then you will see How PAJERO became PEEJARO. 
Cooling System:
I've seen people driving pajero without Coolant reservoir tank & Radiator Fan without Shroud & Bad Radiator Cap.
People don't have respect & knowledge, How the cooling system works precisely.
I've seen many pajeros with radiator-to-coolant reservoir pipe hanging around just like that
OR even if they have reservoir tank, its tank is cracked/leaking
OR its cap is broken OR in open space just like that, loosing all the pressure, means cooling system aint' working at all, you just have to keep filling water after every 2 days OR even after 1 day if much driving is done, many times during heavy traffic-n-go situations OR during long driving, most of the water is already evaporated thru the reservoir pipe & left with little water only, causing damage to radiator-to-engine hose pipe & radiator itself , as well as the whole engine. & people don't realize this.
specially old diesel pajero engines are already under-powered + Turbocharged, which brings the JUICE to full-fill the luxury+economy BOTH at the same time, for the reason you need to keep it in very original state-of-the-art condition as manufactured by Mitsubishi.
Also, if you do any alterations/modifications, make sure you are calculative enuff to match the engineering algorithm of the Mitsubishi.
BIG Tyres:
There's Only 1 BIG Advantage for Big Tyres= SHOW OFF RICER. 
Many people have CRAZE about fitting BIG Tyres. This is fooling urself.
Big Tyre hurts Aerodynamics & Engine Energy.
Offset OR Deep Dish Rims/Tyres also hurt aerodynamics.
It is better to FIT Small but SOLID Quality tyres. 205-215 & 225 is MAXIMUM size.
EXHAUST:
Most people don't even go there. Ever notice OR have little feeling, what going on under there?
BAD Exhaust systems cause Back-Pressure, hence Killing Engine efficiency, & cause Overheating.
FIX The whole EXHAUST System As soon as possible.
OIL:
Most people don't know what OIL to give to their Respective Pajero Engines.
Most people i see go for THICK Weight OILS, High Viscosity, dreaming & thinking that it will be very good for ENGINE. 
People do this because they want to see a Low-Noise Diesel engine.
But they don't know that this will give Bad MPG & Hurt Engine cooling.
My recomendation is to Use a THIN Weight OIL, cause it flows easily & helps Engine to cool down FAST.
USE Good quality company OIL , so when the ENGINE HEATS-UP HARD, the OIL does'nt breaks-up.