Dear Click & Clark,
I am in the process of buying a used 2001 or 2002 Lincoln Navigator. I am relocating to Ghana in West Africa , a tropical rain forest region. My question is I want to equip the SUV with 18 inch wheel and a large tire specifically 285/60/R18 or 275/55/R18 instead of the 255/75/R17 it originally came with . I don’t know if an all season tire or all summer off road all terrain tire will work. Also I am worried about the suspension should I replace it since it seems to be where most Lincoln SUV’s have problems. The proposed SUV I want to purchase has a 110,000 miles on it. The owner told me it is highway mileage but I am not sure if I should have a 90,000 miles maintenance done on it. Please advice as to what my options are as I am confused. I have consulted many mechanics but I seem not to be getting straight answers. Your acknowledgment on the receipt of this letter will be highly appreciated.
Regards,
HO
I suspect there are not many Lincoln Navigators there and your dealer has no idea.
The first thing I would do is to investigate what cars are popular in Ghana for the kind of driving you will be doing and likely buy it there. Few of us have any experience with rain forest or Ghana.
The Navigator will be a real white elephant in Ghana. As the previous poster points out, find out what cars a re popular there.
I spent some time in Nigeria, and aside from some Jeeps, there are no American cars there. They have a lot of imported used European cars, Citroens, Mercedes, some BMWs, and a lot of hand-me-down Japanese vehcles from Europe and Japan.
If I were you, ith navigator is the last vehicle I would take; it is not even a good offraod vehicle compatred with the type of units they have threr; old style Toyotas, Mitsubishi, Nissans, etc. All with good ground clearance, simple engines, and ease of servicing.
The only reason to take a Navigator to Ghana would be to sell it there to a Tribal Chief or government official. Usually the only source of these vehicles are the international auto theft rings who lift them off the streets of US cities, put them in containers and ship them overseas.
Why would you take a Lincoln Navigator to Africa where that brand is not marketed? Even though it is essentially a Ford, even American Ford parts will likely be very difficult to find on that continent, and would have to be imported at extra expense.
In most developing nations, the Toyota Landcruiser is the preferred mode of transportation in the hinterlands. And, Toyota markets some SUVs in Africa that have never been sold in the US, as does Nissan and Mitsubishi. Those are the vehicles that you should be buying, rather than a Lincoln Navigator.
You should buy your vehicle in Africa, rather than having it shipped from the US, as even something like a Toyota Landcruiser from the US will have some equipment (emissions related) that has never been seen in Africa. A US-spec vehicle will be nothing but a headache for you in a developing nation.
Thanks for re-emphasizing more elegantly that US cars are a pain in the butt in third world countries. A stripper Toyota Landcruiser, Nissan Pathfinder, Mitsubishi Montero, etc. is virtually bullet-proof in that environment.
I like the idea of taking a Navigator there to sell to a tribal chief or government official, though! 
To answer your question
The problem with changing your wheels is that lower profile tires will be more susceptible to damage. Roads typically in the third world are terrible but your vehicle may spend its life in the city. If you send it over keep your old rims in case you blow a tire(seemed quite common when I grew up in Alexandria Egypt in our full size Blazer). Pack the thing to the hilt with spare parts too if not easy to acquire where you going.