If you have to ask about the BMW 745Li, it’s highly unlikely you can afford it

Hi Baraza,

What’s your take on the BMW 745Li in terms of maintenance and suitability for Kenyan roads since I don’t see them much on our roads.

What are the pitfalls of maintaining such a beast?

Hello,

The 745Li does have tyres, doesn’t it? That means it is suitable for “Kenyan” roads, which, truthfully speaking, it’s about time we stopped complaining about. Sure, not all of them are mirror-smooth, but then again the kind of person who drives a 745Li is unlikely to haunt the corners of the country where that 745Li would have problems driving through.

People who buy such cars have a high degree of certainty about where they intend to drive them,  and there is an equally high degree of certainty that those places have good — or near-excellent — roads.

If this person chooses to go lifestyling his or her way through remote areas with cattle tracks for access roads, there is a high degree of certainty that person will have an SUV too.

The 7 Series is BMW’s flagship car, and the 745Li specifically comes with a complex V8 engine. What kind of maintenance costs would you expect? Mountainous ones, right?

The 7er is a prime example of, “If you have to ask, you cannot afford it”.

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I would like to thank you for your weekly articles on cars. I am a huge fan of yours. I am in my final year in high school and anything about cars fascinates me.

Now, I have a Nissan Patrol Aventura that I bought at a local car dealer’s late last year and it was performing well. I  made several trips to Meru in it without any problems, and I also drove it to Mombasa. It performed well on the way to Mombasa but before starting my return journey, I  refuelled  at a petrol station there and on reaching Voi, the car jerked and the engine went off. I was doing 120km/h when that happened. I pulled over and tried to ignite it, without success.

I bought a slightly used battery and the car came back to life. I did not exceed 110km/h thereafter but the car behaved the same three more times. Each time I would let it cool before restarting it.

When I got to Nairobi, I took it to a garage and the mechanic suggested that I change the fuel pump. I got a second-hand one which served me well for some time before the  problem came back. What could be the cause of the problem and what I should do about it. You can even recommend a mechanic if you know a good one.

There is also a diff lock button on the dashboard and I am not familiar with how and when to use it. Kindly advise.

Tonny Wycliffe

Hello Wycliffe,

First, I had a university student plotting against the chastity of his female classmates with the help of a German car and now I have you buying a Nissan Patrol while still in high school – or is it a Navara? You said Aventura, right? How much pocket money are young people getting from their parents nowadays? In my day we received just enough to barely stay alive and get our little behinds home once holiday time came around.

You did not specify whether your Patrol runs on diesel or petrol. Your symptoms cover a lot of theories: the initial battery replacement could mean you had a weak battery to start with, but then the car stalled again — three more times—restarting only after you let it cool. That means you could have also suffered from vapour lock as explained above. Or the battery could still be weak, meaning the wiring is tetchy and the battery is either draining or not charging. That means the alternator and its attendant leads might need checking. But then again, you say you got a new fuel pump and the vehicle worked well “for some time” before  the problem reccurred. So is it the fuel pump acting up, or is the electrical power being fed to the fuel pump so excessive that it both drains the battery and eats fuel pumps? This calls for a thorough diagnosis of the car – preferably not by proxy.

The diff lock switch does exactly what it says: it locks the diffs. Let’s start with what a diff (differential ) is. It is a device that does two things: it facilitates torque delivery to a particular axle and also allows for different rotation speeds of tyres on a given axle. The difference in the rotating speeds of tyres on a given axle usually prevents tyre scuffing when taking turns. When turning, especially sharply such as when executing a three-point turn, the inside tyres will tend to rotate much slower than the outside ones.

The thing is, an open diff (which is the “normal” diff) allows what we call slip, i.e the locking percentage might allow for non-rotation of one tyre while the other rotates. This might be compromising in low-traction situations, or when engaging in hardcore, off-road acts that lead to one or more tyres catching air. The torque follows the path of least resistance and is “wasted” as wheelspin, which may be minimised by a limited slip diff (story for another day) or eliminated completely using a diff lock.

What the diff lock does is sort of bind the tyres on the two ends of the axle together, figuratively. They are forced to rotate at the same speed, no matter what. That means loss of traction (or catching air) on one end of the axle has no effect on the other, and there is no wasted torque as the tyre still on the ground is forced along. Think of it as a limited slip diff taken to its logical extreme.

A locking centre diff in turn forces both front and rear axles to rotate at the same speed and receive the same torque, similar to the way a front/rear locking diff forces the tyres on both ends of the axle to rotate at the same speed, which further improves traction in unusually extreme circumstances, such as when the ground is so uneven that two tyres at a time are catching air.

Depending on the model of vehicle, there might be one (mostly rear) locking diff, two (front and rear) or three (front, rear and centre). The oddball Mercedes-Benz G63 AMG 6x6 has five diff locks (three axle diffs and two centre diffs). The newest Nissan Patrol, the Y62, has a diff lock only on the rear axle.

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Dear Baraza,

I have been driving a Toyota Lexus 2.4l for the last three years and wish to upgrade to a used German SUV. I’m torn between a VW Touareg (non-Turbo 2.5l, diesel) and a Land Rover Discovery 3. I’m thinking of the older 2004/2005 models.

Kindly advise on reliability and fuel consumption. Also, how do these German cars compare with Toyota Prado 2.7l engines? I would appreciate your expert opinion because I have been getting very discouraging reviews of these cars from friends and mechanics.

Dominic

The discouraging reviews continue here. The Disco 3 is not very reliable. Time and again I have told readers that the failure of the air suspension is a matter of when, not if. The diesel engine eats its turbos with appalling regularity and being a tiny 2.7, struggles to lug all that weight around. This means that consumption will suffer. The alternative 4.4 litre V8 does not solve this problem with economy.

I have never heard of a diesel-powered Touareg without a turbo, unless the turbo was removed after it left the factory, in which case steer clear. The 2.5 litre  R5 engine is supposed to have a tin snail attached to it (the actual label is 2.5 R5 TDI). The reliability of the Mk I Touareg is a hit-or-miss affair, but don’t hope for the best. Delete the DPF if you choose this car to reduce the odds of expensive maintenance schedules and increased uptime.

The Prado 2.7 is both reliable and economical (relatively), but this comes at the expense of performance. Not that you would want to race a Prado, but sometimes it’s good to have some power in reserve. The thing is, its economy cannot compare to the European cars because the 2.7 is petrol-powered while the 2.5 Touareg and 2.7 Disco are diesel-powered. They have the advantage. It is my assumption that the 4.4 V8 Discovery is not part of this discussion.

*Note: the Land Rover Discovery 3 is American, not German. The Series 1 was British, the Series 2 was German, the Series 3 was American and the Series 4 is Indian. This may sound like claptrap but read up on ownership of the Land Rover and the respective timelines of the Discovery models. You will understand.

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Dear Sir,

l would like to thank you for your  very informative and well-written articles. which  l came across while doing an Internet search on the Toyota Mark X.

Anyway I have a few questions which I hope you can answer

1. What advice would you give to a first-time buyer, in my case it is a 2006, used model with about 53,000km on the clock. l am thinking service and general upkeep information.

2. As an off-roader, I am thinking of getting a second car. I want something diesel but most Japanese imports are petrol. Is it a really big issue whether I go diesel or petrol? I have heard that diesel has better economy, so is cheaper but more problematic when it comes to servicing? The petrol is cheaper, but not to run, from what l hear. What do you recommend? 

3. As far as the options go, I would really love a Prado as it is a Toyota and can be found with a 2.7l capacity, which is something I could live with. I have thought of the Nissan X-Trail which, though smaller, is far cheaper, going for about half the price of a Prado in some cases.

However, given where I live, the mechanics say a Toyota would be  better, the first  reason being that  there are lots of them, so service and parts should, ideally, not be an issue. Nissan, in the days of old, refused to service non-domestic models, which was not the case with Toyota.

As much as I love the Prado, having sampled a friend’s, the cost is prohibitive, to say the least, not to mention the high incidence of carjacking associated with it. Which model, apart from the Prado, would you suggest as an alternative? 

What do you make of the Nissan X-Trail as a cheaper option and, hopefully, not cheap in quality, reliability and overall suitability as an off-roader.

By the way, my main aim is to have a vehicle which can tackle our very bad roads. I am in the Southern African Development Community region.

The other reason is that I love the outdoors and would like  to explore them more in such a car, and as a keen cyclist I would love to access bush trails and also be able to  carry my bike around easily.

The other thing is that I come from a very large family, so it seems prudent to invest in such a car as it can carry more people while also being versatile.

Lastly, there is the village which, as can be expected, is hard to reach so an all-terrain vehicle would be preferable to a sedan.

Chief

Hello Chief,

1. Service and general upkeep costs should not be too prohibitive, provided the car was well maintained by its previous owner, and this is where we pause and take a closer look at the car. A 2006 car with 53,000km on the clock is as nebulous as a strangely quiet man wearing a hat and an overcoat on a sunny day. It is best regarded with the deepest suspicion. Ten years is a long time to rack up only 53,000km; I’d easily expect twice that from a mass-produced, middle-level saloon car. There is the likelihood that the odometer has been tampered with. Ask for the original JEVIC certificate and don’t be surprised if you discover the vehicle was imported with a higher mileage than what it now has.

2. Whatever you heard about petrol versus diesel is mostly true, so it comes down to you: which would you prefer, given the pros and cons of each?

3. The Prado is the obvious contender here, but you have one more logical option besides the sometimes unreliable X-Trail: the Toyota Surf. It might  not carry seven passengers like the Prado, but it is a similar car, sharing engines and platform with the Prado, and has broadly similar capabilities off-road too, with the added bonus of being better optimised for on-road use via the independent front suspension and having a lower centre of gravity. I am not sure how attractive it is to twoccers, but then again, if you take the preemptive measures I once listed in this column against calling attention to yourself as a possible candidate for relief from ownership, you can live a pain-free and worry-less automotive life.