Test­ing, test­ing… test­ing?

Leisure Wheels (South Africa) - - CONTENTS - Text: Danie Botha.

Cruiser 3.0D-4D gets the treat­ment in Lesotho

When Toy­ota 4x4 spe­cial­ist N1 4x4 re­alised there was a gap in the mar­ket for Land Cruiser 4.2D own­ers who were look­ing to re­place the tough but low-on-power 1HZ six-cylin­der oil burner, they looked the way of the Hilux/For­tuner 3.0D-4D engine. In de­vel­op­ment for more than a year, we joined the team on one of their fi­nal re­search and de­vel­op­ment trips to Lesotho, for some high al­ti­tude tests.

WE’VE re­cently spent a lot of time in Lesotho. We even took our an­nual Ad­ven­ture there (you can read about it else­where in this is­sue).

On that trip though, we se­lected a route to cater for Av­er­age Joe driv­ers with very lim­ited 4×4 driv­ing ex­pe­ri­ence, driv­ing stock stan­dard ve­hi­cles. So no mad­cap Grade 5 ob­sta­cles were on the menu.

The team from N1 4×4 though, had com­pletely the op­po­site in mind: they were look­ing for some of the most ex­treme high al­ti­tude tracks they could find. At least Grade 5 trails.

Be­fore we get to our re­search and de­vel­op­ment trip though, some back­ground on N1 4×4’s unique take on the Cruiser pow­er­train, us­ing the fa­mil­iar four-cylin­der D4-D that also pow­ers a gazil­lion Hilux

bakkies and For­tuner SUVs run­ning around our roads.

Spe­cial­is­ing in Toy­ota’s hardy Land Cruiser, the N1 4×4 team iden­ti­fied a need for a suit­able engine re­place­ment for high mileage Cruiser 4.2Ds. Al­though the nat­u­rally aspirated 4.2Ds are as tough as nails, their on-road per­for­mance is no­to­ri­ously lack­ing in, well... just about ev­ery depart­ment.

Main­tain­ing 120km/h on the open road is all but a pipedream for a 4.2D driver. Want to tow some­thing heavy with a 4.2D over a long dis­tance? Not a good plan.

In­stead of swap­ping the leg­endary 1HZ 4.2-litre straight­six diesel engine with a sim­i­lar heart, why not up­grade to some­thing that rec­ti­fies some of the 1HZ engine’s ob­vi­ous short­com­ings? Like an engine that will en­sure a cruis­ing speed of 120km/h is a re­al­is­tic op­tion, up hill and down dale.

En­ter Toy­ota’s well-proven 3.0D-4D four-cylin­der engine. But it’s not quite as sim­ple as ex­tract­ing the 1HZ mill from a Cruiser’s engine bay and in­sert­ing the three-litre mo­tor.


Be­sides the ob­vi­ous cus­tom parts such as engine mount­ings and adap­tor plates, one of the big­gest chal­lenges in a con­ver­sion such as this is get­ting the elec­tron­ics and elec­tri­cal sys­tems sorted.

The N1 4×4 team spent many months try­ing to source real McCoy wiring har­ness con­nec­tor plugs, and finally man­aged to do a bulk pur­chase in Aus­tralia.

This was fol­lowed by months of ex­per­i­ment­ing with dif­fer­ent tur­bocharger set-ups on the 3.0D4-D engine; the grey sin­gle cab you see on these pages was used as the of­fi­cial de­vel­op­ment unit. And things didn’t al­ways go ac­cord­ing to plan. N1 4×4’s Louis We­ichelt ex­plains.

“We were do­ing tests with dif­fer­ent types and sizes of hy­brid tur­bocharger, to find the ideal mid­dle ground be­tween power and re­li­a­bil­ity. The stock D4-D turbo doesn’t do more than 1.6 bar boost. If you push past that mark, re­li­a­bil­ity is com­pro­mised. One day we landed up on a stretch of road we of­ten used for high-speed tests. I was go­ing quite fast, when I heard a strange pop­ping sound and the next mo­ment, a big dent in the bon­net, along with a loss of power... it’s all part of the process.”

The ideal was to find a larger ca­pac­ity tur­bocharger that wouldn’t be spin­ning near its

max­i­mum ca­pac­ity more of­ten than not. And in time that tur­bocharger was found.

The engine man­age­ment system is also a vi­tal in­gre­di­ent, and in this depart­ment, the team opted for the Aussie-made Motec system, a lead­ing brand in mo­tor­sport.

“It’s a bit more ex­pen­sive than other sys­tems but you can lit­er­ally ad­just the engine pa­ram­e­ters ex­actly how you want them, for ev­ery 100r/min,” says the com­pany’s Cliff We­ichelt.

The N1 4×4 off-road rac­ing Land Cruiser uses a Motec system. As does ev­ery other top cross-coun­try rally team in the coun­try, in­clud­ing the Toy­ota Ga­zoo Rac­ing SA fac­tory team that com­petes in the Dakar Rally.

The stan­dard 4.2D fi­nal drive ratio is 3.9:1 and is ideal for lug­ging heavy stuff over rough ter­rain but not so great when you drive at higher speeds, when the engine revs quite high. So the N1 4×4 team swapped the stan­dard ratio for the V8 D-4D Cruiser’s 4.3:1 ratio. With a healthy in­crease in power, and the longer fi­nal drive, cruis­ing at 120km/h would not only be a re­al­is­tic op­tion, but also a more com­fort­able, less noisy af­fair.

With the suit­able hy­brid tur­bocharger fit­ted and tested, a per­for­mance ex­haust from De Graaff added and the engine man­age­ment system tuned, the three-litre engine de­liv­ered about 170kW and around 500Nm of torque.

How­ever, it had never been tested at high al­ti­tude. So a 1 600km round trip was planned to Lesotho… peak­ing at around 3 300m above sea level it doesn’t get higher than this in southern Africa.


If there’s one thing you can’t ac­cuse a Toy­ota Land Cruiser pickup of, it’s that it is a re­fined, com­fort­able beast. It was just af­ter 5am, and we were driv­ing the grey pick-up out of the city. The clutch is heavy. The steer­ing is vague. The cabin is noisy, filled with diesel clat­ter.

But when you plant your right foot... golly! Sure, there is a bit of lag to work around, what with the taller gear ra­tios, but when that hy­brid turbo starts boost­ing, oh boy! Your head is snapped back, the rear wheel with the least grip bat­tles for trac­tion, as the Cruiser blasts for­wards like a bat out of hell. We hit the high­way, and in fifth gear an­other trait be­comes ob­vi­ous: the 3.0D4-D Cruiser is com­fort­able at 120km/h. If you want to over­take, there’s no need to touch the gear lever ei­ther – a dab of right foot will see the Cruiser blast for­ward, pick­ing up speed at a prodi­gious pace.

We reached Van Ree­nen’s Pass in good time.

We were run­ning be­hind the sec­ond Cruiser, at around 80km/h. Un­sighted road­works in the fast lane of this no­to­ri­ously dan­ger­ous pass sud­denly filled the road, along with a string of slow-mov­ing trucks in the left lane. The Cruiser in front of us jumped on the brakes, and we fol­lowed suit mo­ments later... but we came oh-so-close to re­ar­rang­ing the tail of the white Cruiser with our LAS bull bar.

The Cruiser’s brakes have never been its most out­stand­ing qual­ity. N1 4×4 of­fers a Power­brake up­grade for the

“It had never been tested at high al­ti­tude. So a 1 600km round trip was planned to Lesotho… peak­ing at around 3 300m above sea level it doesn’t get higher than this in southern Africa”

Cruiser, which we would most cer­tainly rec­om­mend. It will add about R7 000 to your bill.

Later, af­ter a few stops along the way, we reached the fi­nal stretch of dirt road be­fore the South African border post. The plan was to head up Sani Pass. SURGING AHEAD

N1 4×4’s Motec expert – con­sid­ered to be the best in the South African busi­ness – had loaded a tem­po­rary high al­ti­tude pro­gramme for the as­cent to more than 3 000m.

But, as we were climb­ing higher, head­ing to­wards Lesotho, it be­came clear that the D-4D engine wasn’t en­tirely happy. All the power was there but the turbo lag be­came more pro­nounced. Both Cruis­ers also dis­played a new ‘surging’ trait, as we made our way up the pass.

We made it to the Lesotho border post with­out in­ci­dent, it was only when we restarted the en­gines af­ter com­plet­ing the for­mal­i­ties that there was an ini­tial re­luc­tance to idle. Once we revved it a bit, it was fine again.

We made it to Sani Moun­tain Lodge, for our first night in Lesotho. We were plan­ning to tackle a tough 4×4 track lead­ing to the Let­seng Di­a­mond Mine the next day. Af­ter the 4am start, we all tucked in early as we were ex­pect­ing to be bat­tling with some rocks and boul­ders all of the next day.


Af­ter break­fast and af­ter set­tling the bills, we loaded up our gear and... there was a prob­lem.

Both Land Cruis­ers re­fused to start. Each engine would spin. Then, for the briefest of mo­ments, it would seem as if it was fir­ing to life. But then it would die again. Some phone calls back to South Africa traced the prob­lem to the engine man­age­ment system, clearly the de­fault high al­ti­tude set­tings were not do­ing the trick.

We tried to ‘charge’ the glow plugs di­rectly from the bat­tery, to see if that would help. But it didn’t. Next we tried spray­ing some de­odor­ant into the in­take man­i­fold but that also made no dif­fer­ence.

As a last re­sort, we hooked up the Cruis­ers be­hind the lodge’s Cruiser V6, and both were soon run­ning again. Clearly the elec­tron­ics and the high al­ti­tude were not on the same page though, which left us with a co­nun­drum: do we push on to the des­o­late val­ley near Let­seng mine? We were pretty sure the Cruiser would make the trip to Chalets in the Sky but what about the next morn­ing? There would be no Cruiser V6 to tow our lor­ries if they again re­fused to start (which we ex­pected).

We de­cided to play it safe: we’d head to Chalets in the Sky, ne­go­ti­at­ing some dirt roads and a few river cross­ings along way. But in­stead of stay­ing over, we’d

con­tinue to Camel­roc in South Africa, just out­side Lesotho, near the Cale­don­spoort Post.

On the beau­ti­ful moun­tain pass that leads to Chalets in the Sky, we had a mo­ment of red mist. You see, the grey Cruiser is fit­ted with a trick Dobin­son sus­pen­sion with ex­ter­nal reser­voirs. It is also fit­ted with Cooper Dis­cov­erer STT Pro tyres. There was no weight on the ‘bak’.

So, on the drive up the pass, back to the main road, we gave the grey Cruiser free rein... and did it hop and skip up that pass! Keep­ing the tur­bocharger on the boil en­sures plenty of horses. Even with 4WD en­gaged and the Coop­ers pro­vid­ing plenty of trac­tion, you can get all four wheels spin­ning on the exit out of the cor­ners.

We reached the es­carp­ment quite a bit ahead of the white Cruiser, which was also car­ry­ing all the sup­plies. But watch­ing it head­ing up the pass, it did seem to go unusu­ally slow. The rea­son was soon ap­par­ent: a boost pipe had developed a leak, cour­tesy of some chaf­ing from the power steer­ing pul­ley.

It ap­peared as if the cus­tom­made rub­ber pipe had ex­panded a lot at the high al­ti­tude, and un­der the full load, caus­ing it to come into contact with the pul­ley. Wel­come to the world of re­search and de­vel­op­ment. This was ex­actly why we were in Lesotho. Thicker-skinned pipes are now in the, er, in the pipe­line, for the up­grade, to en­sure there is no more ex­pan­sion (along with a loss of power). And no more contact with the pul­ley.

More sturdy pipes will also im­prove engine and tur­bocharger re­sponse.

We reached Camel­roc just be­fore dark, af­ter a day spent on the road. The food was ex­cel­lent, and the whisky, too. We had a right royal time.


Camel­roc is a place of many sur­prises. Not only does it of­fer a pic­turesque setting in the Ma­luti Moun­tains com­bined with very com­fort­able lodg­ings, it also boasts a 4×4 trail.

Heavy rains had caused parts of the track to be washed away, turn­ing Grade 3 sec­tions of the track into at least Grade 4s. A stan­dard dou­ble cab would not be happy on these tweespoor tracks.

The Cruis­ers though, were right at home in the rough stuff. In fact, they made it look too easy. No drama, no spin­ning tyres; all very calm and col­lected. On some of the steep climbs the driver could take his feet com­pletely away from the ped­als, and the Cruiser would ‘idle’ up the in­cline, no wor­ries at all.

On the steep­est of the muddy down­hill bits, the slightly higher gear ratio re­quired some deft brak­ing from the driv­ers. It ran just a smidgeon too fast in first gear, low range, re­quir­ing the ap­pli­ca­tion of the brakes

to keep the speed in check.

The Toy­otas thor­oughly im­pressed with their 4×4 abil­ity. The com­bi­na­tion of solid axles, lock­ers for both axles, plenty of clear­ance and ar­tic­u­la­tion af­forded by the Dobin­son sus­pen­sion, the trac­tion of the all-ter­rain tyres and the D4-D engine en­sure that these Cruis­ers can go any­where, any­time.


By the time you read this, the N1 4×4 tech­ni­cal team would have been back to Lesotho with their com­put­ers to pro­gramme the Motec engine man­age­ment system for the higher al­ti­tudes. And the new turbo pipes will be fit­ted.

In short, the re­search and de­vel­op­ment of the con­ver­sion will be done and the first pro­duc­tion-ready Cruiser 3.0D4-Ds will be de­liv­ered to their new own­ers.

To the big ques­tion: how much? N1 4×4 says it can do the 3.0D4-D con­ver­sion for R150 000. Or, the com­pany can sup­ply a re­con­di­tioned Cruiser (like the white sin­gle cab in these pho­tos, ex­clud­ing the canopy) for about R350 000. Good news is that the con­ver­sion is not lim­ited to the sin­gle cab. You can have a dou­ble cab and the sta­tion wagon con­verted, too.

Is it worth it? Af­ter spend­ing nearly 1 500km driv­ing the 3.0D4-D Cruiser, we reckon it is.

As N1 4×4’s Cliff We­ichelt rightly points out, this con­ver­sion is not aimed at own­ers of the V8 D4-D or four-litre V6 petrol Cruis­ers.

“The V8 and V6 own­ers are happy with the power and drive­abil­ity of their Cruis­ers. 4.2D own­ers, on the other hand, need more power, cruis­ing abil­ity and towing ca­pa­bil­ity. Our con­ver­sion cov­ers those re­quire­ments com­pre­hen­sively,” says We­ichelt.

N1 4×4 is not rest­ing on its lau­rels ei­ther. While the first

D-4D con­ver­sions are about to be de­liv­ered to cus­tomers, the tech­ni­cal de­vel­op­ment team is fi­nal­is­ing the last few de­tails of a new D-4D Cruiser de­vel­op­ment, linked to an au­to­matic gear­box.

What about the lat­est gen­er­a­tion 2.8GD-6 mill? Wouldn’t that be an even bet­ter fit in the Cruiser, we asked We­ichelt.

“That is the next step. At this time, the 2.8-litre engine is still too scarce, and too ex­pen­sive, to make the con­ver­sion vi­able. That will change in a few years of course, and we’ll be ready to do the trans­plant,” ex­plains the Perth-based N1 4×4 boss.

We con­clude this tale with a lit­tle in­ci­dent which hap­pened as we ar­rived back in the con­crete jun­gle, driv­ing on Ont­dekkers Road on the West Rand. Stop­ping at a red traffic light, we ob­served a pimped Nis­san Navara 2.5dCi parked next to us, sport­ing a huge set of mags with such a thin layer of rub­ber be­tween the wheels and the road, it seemed as if there was ac­tu­ally no rub­ber at all.

We no­ticed the driver of said Nis­san cu­ri­ously eye­ing the grey Cruiser parked next to it. So, when the light turned green, we half ex­pected the man in the Nis­san to show this Cruiser just how fast those mag wheels re­ally are. Of course, we obliged... and the 2.4-ton Cruiser showed that Navara a clean pair of Cooper tyres, pulling away from it at a rate that sur­prised even us.

We re­ally en­joyed that. And we also en­joyed the old-school charms of the Land Cruiser. At R350 000 for a ba­sic model with­out too many thrills and spills, it of­fers a lot of re­con­di­tioned 4×4 for the money.

Above, top to bot­tom: Sailing through an­other river, in Lesotho. A re­ally tough 4×4 ob­sta­cle on the Camel­roc 4x4 trail – but the Toy­otas rose to the chal­lenge. Be­low: In for­ma­tion the Cruiser pick­ups ne­go­ti­ate a river cross­ing near Fouries­burg....

Clock­wise from top: An­other day, an­other river to cross. This one was near the Let­seng Di­a­mond Mine in Lesotho. At the heart of it all, Toy­ota’s 1KD-FTV engine, boast­ing around 170kW of power. This was the ve­hi­cle’s first high al­ti­tude test. And, at...

Op­po­site page: The N1 4×4 Land Cruiser 3.04-D test mule, at 3 000m above sea level. Above, clock­wise from top: On the open road, the Cruiser 3.0D-4D can eas­ily main­tain 120km/h in top gear, no mat­ter hills or dales. Sign at the top of Sani Pass…...

Be­low: The Cruiser 3.0D-4D test mule fea­tures a whole lot of up­grades, in­clud­ing an LAS bull bar, Hella spot­lights, snorkel, up­graded sus­pen­sion, dif­fer­ent mag wheels and Cooper Dis­cov­erer STT Pro tyres, and a cus­tom ‘bak’.

Newspapers in English

Newspapers from South Africa

© PressReader. All rights reserved.