alexa Would it be wise to invest in this automatic transmission truck? - Daily Nation

Would it be wise to invest in this automatic transmission truck?

Wednesday February 5 2020

Toyota Toyoace

I need advice concerning the Toyota Toyoace truck. PHOTO | COURTESY 

BARAZA JM
By BARAZA JM
More by this Author

Hi Baraza,

I am a regular reader of your articles. I need advice concerning the Toyota Toyoace truck. I am interested in this car for regular deliveries but I’m concerned that these days they come in automatic transmission and are diesel engines. Kindly advise me since it is the first time I have seen a light-duty commercial truck with automatic transmission. I fear it will be problematic in the long run.

Regards,

Harsh

Hi Harsh,

There is a time some way back when I busted several myths and enlightened people on a few fallacies that pervade the industry and are tenaciously held on to by people for whom ego takes precedence over facts - the type who cannot accept to be corrected and like to call on immeasurable variables such as "experience" whenever they get cornered with science and mathematics. You can drive an automatic car for 100 years but you'll never understand how it works unless someone actually teaches you.

Advertisement

That said, one of the fallacies in question is the superiority of a manual transmission over an autobox one as far as commercial vehicles go. This is false, already stated. Here are the reasons why:

1. Regular automatic transmissions use a torque converter - a fluid clutch - rather than a positive clutch or friction clutch. This in itself has several advantages - the most obvious being you cannot burn the clutch in a slushmatic car, but you can with a manual. And it happens frequently, especially with PSVs. I will give an example:

Scania AB placed the kibosh on manual transmissions in their products citing research which showed the automatic (Opticruise ®) version is a lot more efficient and has longer life, which can be interpreted to mean "is less prone to damage". Scania EA, the local outlet of the heavy commercial giant, were not so soft: they said that they are ending the era of the manual transmission, which had last been used for bus application in the F310HB chassis. From now on the F310 comes with an automatic. Reason? Bus drivers were going through clutches and transmissions like a hurricane called Katrina sweeping through a New Orleans neighbourhood. I have many friends in the bus industry, and one of them was unequivocal when he told me in confidence that the company he worked for was seriously considering replacing some of the drivers because they didn't seem to understand how to use a clutch pedal properly. Maintenance costs were becoming stratospheric.

2. Slippage: The torque converter works on the principal of fluid being used to transfer torque from the engine rotation to the gearbox rotation, as compared to a friction clutch that involves two surfaces mating to transfer torque from engine to gearbox. Without delving in too deep into engineering, this essentially means that you can drive at very low speeds in an automatic without stalling and without having to slip the plates in the clutch which burns them out. This is great for maneuverability, a common requirement for delivery-based commercial vehicles.

3. Torque multiplication: Ever noticed how automatic cars have a creep feature that can even work uphill? Sure, you can creep with a manual off-throttle as well, but it takes a lot of deft footwork and occurs at the expense of clutch life (see 1 above), and while you may creep uphill with a manual theoretically, I'd like to see you do it. This ability of the autobox to "balance" uphill with no throttle is from both the wet clutch with its ability to create infinitely variable lockup between completely off and completely on, and also from the key difference between a manual and an automatic: the manual transmission engages different sets of gears to achieve the various ratios, while an automatic uses the same set of gears to produce different ratios. It is almost like a CVT. The planetary gears are what makes this possible. How a planetary gearset works exactly is something I'm not sure you will understand when explained within the confines of a two-page newspaper spread. You will need audio-visual aid for this.

4. Driver fatigue: Now, while the fun and engagement aspect of using a manual transmission is subjective and a matter of preference, one thing remains universal: extended and continuous usage can get tiring after a while, more so in vehicles with a large number of gear ratios. Several years ago I test-drove a Scania R420 with a 12-speed manual and I must say it was not as easy as the truck drivers make it look. For one, the gears are arranged as three basic speeds (1, 2, 3) with split into high and low to make six (1L, 1H 2L, 2H, 3L, 3H) and these six speeds are the doubled using a range divider to make 12, so 1L becomes 7, 1H becomes 8, 2L becomes 9 etc, etc. It is confusing. Then, the relative low ratios mean you have barely cracked 40km/h between 1st gear and 7th gear, now picture wrestling this mess with a 40-tonne payload in traffic while balancing the clutch to avoid stalling. It gets very old very fast. I don't need to mention the number of times you will change gear between the port of Mombasa and the Malaba border post in such a truck.

5. Driver error: Besides burning the clutch, certain habits or mistakes that drivers make when driving manuals are overridden by the automatic transmission's brain. I'm referring to overreving or short-shifting. Both of these are destructive to engine health: overrevving is hard on fuel and you risk blowing the engine. Short-shifting strains both engine and gearbox, and in some cases, forces the fuel system to run rich to compensate for insufficient power/torque resulting from using too high a gear for a given road speed. Running rich leads to enhanced oil degradation and gradual engine damage as oil is washed off the cylinder walls by the thick petrol mist that comes from overfuelling.

* * * * *

The trick to owning and operating an automatic is simple: preventative maintenance and proper use. Keep the transmission fluid at the correct level and in good condition, and avoid driving styles rich in transmission "shocks" such as getting into gear (reverse or drive) while the vehicle is in motion. The same applies to Park. Only engage Park when the vehicle has completely stopped. No freewheeling. Forget about disengaging overdrive, if you don't know how to use it then you don't need to know. I tried explaining it once and... yeah. I understood why Car Clinic is so popular. People know precious little about the intricacies of automotive operations.

Baraza, tell me, is it possible to create a super 4x4?

I dare say, the best example of this
I dare say, the best example of this combination is, ahem, Land Rover. PHOTO| FILE| NATION MEDIA GROUP

Hi JM,

Still following you religiously. Muscle SUVs offer high and low range 4-wheel drive with diff lock. Pretty versatile off road. Crossovers have ‘all wheel’ drive (but are basically front wheel drives). Models such as Subaru toss in selective torque transmission to wheels that lose traction. Great for snow and sludge, but poor off road. They don’t have a transfer box like their bigger sisters. Now, is it possible to combine the two systems to create a super 4x4?

Maddo

Greetings, Oh Great Cartoonist!

Subarus are not as poor off road as you may think, as has been proved repeatedly by pioneering adventurers of massive testicular fortitude who have ventured forth into the wild in their Foresters and rushed in where Pajeros fear to tread. Such an instance was witnessed by yours truly and the occupants of a convoy comprising about 18 or 20 other cars when two SH5 Foresters went into the Chalbi, and then came out of the Chalbi under my guidance and leadership.

The climax of the story here is: the two Foresters, one black, one white, managed to traverse — quite effortlessly, I must add — a gluey, watery hellhole of quagmire that had trapped both a Land Rover Defender 90 and a Land Cruiser 70 Series troop carrier. There are photos and videos of this, in case you are interested. You were saying something about Subarus being poor off-road?

(Yes, I know driver skill also plays a part in how to go off-roading because I had a Land Cruiser Prado 120 Series, and I daintily and nonchalantly sauntered through that cesspit like I was going to the shop, but do I say? I have had a lot of training in various driving manoeuvres, so it’s not just humble-bragging, I’m actually a professional and good at what I do.

Having blown my trumpet, I must add: the mud pit that trapped the Landy and the Cruiser was not one to be trifled with. Both cars were up to their door handles in the kind of dark, sticky clag that makes disgusting suction noises when you try to walk in it. The location was about halfway between South Horr and Laisamis. The time was mid-afternoon. The adventure was The Great Run’s 16th instalment, which I named the Extension Level Event as a play on the phrase “extinction level event”, and oh my, we almost went extinct. The mud came from a flash flood in a place known for flash floods and as we tried to unstick the two “muscle” SUVs — your words, not mine — the sky was rapidly darkening to our left. If the rain, or goodness forbid, another flash flood had found us still mucking about at that spot, we’d have had it).

Now, back to the lecture at hand. Perfection is expected and I’m feeling that demand, so here is your answer: it’s possible to combine the two systems and create a super 4x4. Not only is it possible, but it has been done to varying degrees over the past several years by different manufacturers, but I dare say, the best example of this combination is, ahem, Land Rover. Don’t laugh, let me explain.

They have this thing called the Terrain Response System, which has since been widely plagiarised and renamed by other manufacturers all over the industry. It works like this: while an AWD system is road biased and tends to channel torque to one axle until slippage occurs then the torque is directed to the other axle, and while a full -on 4WD requires human intervention to engage/disengage diff locks and low range, what the Terrain Response System does is combine all these into a suite of electronically controlled presets that only call for the press of a button to activate. In the “Road” setting for example, the vehicle acts like a typical AWD: torque is biased towards one axle or both depending on the surface and handling characteristics.

In any of the “Off Road” settings, the vehicle acts like a full-on 4WD, for example, the “Rock” setting automatically locks all the diffs and puts the vehicle in low range while dialling back throttle response to prevent jerking.

The “Sand” setting turns off traction control and opens the centre diff. The “mud” setting amplifies throttle response and locks the centre diff, hill descent control puts the transmission in full 4WD and sends it into low range, et cetera et cetera.

All these settings are accessible at the push of a button; you don’t need to memorise all the prerequisite transmission modes (range engagement, locking diffs etc) for each type of surface as you would in a traditional 4WD setup such as the one found in the 70 Series.

I must say the system works very well. I have test-driven a vast number of Land Rover vehicles over a long period of time, and as pioneers of this duality, they have nailed it perfectly. Pick any Land Rover (except the Defender) and you will Discover (pun intended) that they have impeccable and very car-like tarmac manners.

Stray off the hard-pack and start fiddling with the Terrain Response System and... Land Cruisers and Jeeps are not going to drive anywhere your car cannot. It is ingenuous, which is why it has been widely copied. Land Rover’s former owners, Ford, have equipped just such a system in the F150 SVT Raptor.

Advertisement