Kia Mohave with mileage: vagaries of ABS, a successful 8-speed and a near-perfect diesel

Running gear

Braking system

The braking system is simple in design and has a good margin of performance. The discs in the front are 328 mm in diameter, which is enough for Mohave with a diesel, if the driver adequately drives the car and does not confuse it with a racing bolide. That’s probably not enough for the V8 versions, but for lack of any, it will remain a mystery.

At the rear, the discs are only slightly smaller, 324mm, but that’s because the hub houses the drum handlebar mechanisms. The scheme is not very successful from the point of view of service life of brake shoes, but hardly anybody will drift in such car. But the mechanism is simple and reliable. Even a foot drive of “handbrake” is not a problem, breakages happen seldom.

The resource of pads is really not so large, but with such mass of the car, 30-40 thousand kilometers on one set – it’s already not bad. The more so, that calipers will surely pass their 5 years before replacement of dust covers, and further all depends on maintenance. If you do not smear unnecessary and do not try to paint them, the maximum you will have to change the caliper pins.

Front brake pads

One disadvantage is still there – the choice of brake pads is minimal, except for the original there are almost no options.

And ABS is capricious here. But it is half of trouble, in fact work of ABS system sensors is closely connected with work of a full drive system. When ABS breaks, the all-wheel drive is disconnected or works incorrectly, which is often even worse than total system failure. Unfortunately, the location of the sensors and the quality of wiring on them is not the best, breakdowns of connectors and wiring occur and are not so rare. And, what is the most unpleasant, when exercising in mud there are chances to catch something hard in the gap between the sensor and comb with breakage of both. The comb itself, by the way, is slowly but surely rotting due to the accumulation of dirt in the cavity. How it gets there is still a little-explored question.

Suspension

For its class the car steers rather decently – better, than you expect. The matter is rather not in a suspension, but in a frame and body’s durability on torsion. Everything is excellent with comfort too, if wheels are of stock size and body supports are intact. Their destruction is a rarity, but sometimes you can meet cars with strongly sagging supports, and it is necessary to search the reasons of noise and vibrations transmission to the body from suspensions, starting from these elements.

The wheel suspension is rather advanced here. In front is classic double wishbone suspension, in back is hybrid of double wishbone and multilever suspension – the main two levers are in fact self-sufficient and they carry the main load, but the guiding device has two small links, which provide change of convergence.

Everything is made quite monumentally, and the service life of the car on good roads and in the city mode of 100+ thousand is almost guaranteed. Almost all wearing elements are replaceable and inexpensive. Thus, ball bearings of front upper and lower levers, all silent blocks in front suspension and many in rear suspension are replaced. The unpleasant moments are the use of stuck camber bolt at the front lower arm and non-replaceable ball bearing at the expensive upper arm of rear suspension. It is also worth to mention weak hub bearings: sometimes their life time is not up to 150 thousand, and they do not like side impacts. It is also possible to scold weak shock absorber support in front suspension, its cushion breaks strongly when exploiting on bad roads.

The bulk of Mohave owners remember about the suspension only because of the failure of pneumatics on the rear axle – almost all Russian cars have it. And this means that there are a lot of nice little things that can cause a lot of trouble.

Replacement under warranty of expensive (200 euros a piece) level sensors – the main amusement of owners of new cars. In regions with wet climate, the problems start with a run of 30 thousand kilometers. Dealers change mainly sensors, there are two of them, together with levers. The nuance is that the sensor itself is usually alive and well, the failures are connected with the bad connector, in which with time moisture gets, and it oxidizes on the sensor. Simply cleaning the connector can bring the sensor back to life, but for normal operation it is advisable to dry, lubricate and seal the connectors.

The bracket of the sensor rod is flexible, on the one hand, it allows adjusting the level of the body and xenon without the help of electronics, but on the other hand, the bracket itself tilts a little bit with time, causing a roll, which should be eliminated.

The resource of the pump and air cylinders is quite high, with a properly functioning valve block and flushing they last 150 and 200 thousand kilometers. But the cylinder flushing is usually neglected, and the valve block sometimes fails. As a result, a cylinder usually has to be replaced due to slow leakage or even explosion (it also happens). Since such cars are often used for long trips and for trips off-the-road, and it is a pity to refuse from pneumatics, many people put “reserve” – valves of pressure relief and manual pumping line, putting it in the cabin. It allows “lifting” the car in case of broken sensor, dead pump or clogged line and avoid tank explosion due to over-pumping.

And to disconnect pneumatics is simple, blessing the control unit is located under the driver’s seat and there is no complicated manipulations to remove the connector. Sometimes at failure of sensors, it is enough to reset the block at necessary moment, when there is no roll of the car, and it will allow to get to service.

Steering

The steering here is with the usual steering rack GUR. Resource isn’t bad, the pressure line leaks mostly at 200+ mileage. The rack itself knocks a little already at 50 thousand runs, but it does not leak, and the knocks are weakly audible.

Here the knocks from the steering column can be heard much better, and if the “comfort output” is on, the chances of increased wear of the steering column splined joint are high. Once again, the trouble with the Mohave is there are no non-original or remanufactured steering racks. Only repair or expensive original.

Transmission
Common problems.

If you think the trouble with the splines has passed over the Mohave, no. There is a full order with it. I mean, the front wheel shaft tails are chattering in the CVTs, which is causing vibration in the transmission. As usual, the reason is weak duster and weak metal. As a result, the dealer recommends changing the intermediate shaft and the right CV joint. The budget is 450 euros for parts and work. If you can save money on a CVR, you can get by with 350, but the shaft is only available as original.

The problem appears on cars literally from four to five years old, except, perhaps, in the most southern and dry regions. If splines are still in order, then thick grease helps, and if there is already a backlash and teeth profile is broken, the connection is often assembled with epoxy or sealant of strong fixation. Restoration with shank welding and milling is available only to those who can find a good machining specialist (they are few). And here the drilled holes with inserted bolt is “kolhoz” in its purest form, and it is better to avoid it.

Front driveshaft in cars was even changed under recall campaign because of early wear of a cross shaft, but cars with worn shafts can be found. The cause of small vibrations on acceleration may be not only splines, but also a cardan shaft. Front driveshaft CV joints are strong enough and break seldom. The rear driveshaft has had no inherent problems. But at 130+ miles, you can expect the suspension bearing damper to fail and the rear crossmember to wear. The splines here are quite successful, wedging and corroding are rare.

The rear and front gearbox, if to watch oil level and change it at least sometimes (it is better to do it once in 60 thousand), are quite reliable. Leaks due to wear of seals can happen, and breathers can let water in, while overcoming fords one should be careful and it is better to check axle oil for emulsion at once.

Automatic Transmissions

The gearboxes on the Mohave are only automatic, but they are different. Diesel engines are used 6-speed ZF 6HP26, after 2011 the new 8-speed ZF gearbox has been presented with the code A8TR1. Characteristically, it is largely “related” to the ZF 8HP range. The cars with V8 engines are equipped with the same types of automatic transmission as the ones with diesel engines, but the cars with 4.6 can’t be found in Russia. It is possible to find a car with a gasoline V6 3.8 liter, it has a 5-speed Jatco A5SR2/JR507A.

The first generation of 6-speed transmission from ZF (6HP26) is remembered by many problems, but the later versions of this automatic transmission are unified with 6HP28, six-speed ZF of the second generation, and therefore noticeably more reliable. Recall that the main features of this design is the use of kinematic scheme with a number of Lepelletier, allowing to get six gears, without increasing the size of the mechanism. Also low angular speeds of satellites, usage of scheme with low working pressure and small oil consumption, usage of hydroblock construction with combination of sensor board, control unit in block body (so called mechatronic), and also usage of partial and sliding blocking of GDT in most operating modes are characteristic for it. In normal mode, the GDT works only when cold, and only in lower gears. Sliding lockup is used in all power modes, in this case the friction lockup of GDT works as a clutch and transmits torque, allowing to increase efficiency of hydraulic transmission. And as soon as the opportunity arises, the lockup becomes almost full. But exactly that almost – to minimize torsional vibration transmission the friction is not blocked completely, providing minimal slip at all times. Among the interesting features should be noted the built-in electronic thermostat and separately in the hydraulic circuit pressure regulation and separately in the lubricating circuit of the mechanical part.

As a result, ZF managed to create an automatic transmission which has a very high efficiency in all modes, and very high performance, combined with excellent opportunities for the transmission of torque. Even an “average” series ZF 6HP26 has a torque reserve of at least 600 Nm, which allows easily withstand powerful gasoline engines and diesel engines up to 250-300 hp. But there is also the other side of the coin.

Constant use of the torque converter lockup (TCL) in sliding mode causes an equally constant contamination of oil with products of lockup friction wear. A hydraulic clutch part that is too weak is prone to overload failures as the load increases due to friction wear or lockup hydraulic errors. The oil pump of the box and all solenoids are strongly worn, and first of all the solenoids for pressure regulation and locking of GDT, and here they are made according to Aisin scheme, with channels in the body of the hydroblock plate. And not only the solenoid itself is wearing out, but also the body of hydroblock, which is much more difficult to replace. The use of the lead free bronze for the bushings, combined with the minimum working pressure in the slide bearings in addition provides their high wear and vibration in operation. And besides the design has some weak points like seals of the plastic filter sump, rubber seals-adapters between the hydro-block and oil channels, seals of the wiring harness – so called “glasses” and seals.

The strengths of the box, except dynamics and efficiency, are good quality of self-diagnostics and high adaptability limits. The valves have a huge working range, and it is more than enough even for the work of a very worn mechanism, adaptation to the old oil, its overheating and work with load on cold oil. Even half-dead automatic transmission can go smoothly, without bumps and jerks. Electronics “knows” very well the quality of work of all units, and with a simple scanner you can see how worn out the box is.

It’s a pity that if you change the oil “according to regulations”, once every 60,000 km, or even less frequently, as it is the case with BMW and Audi, and also often press the gas pedal, the box will not live long. Leaks, overheating, wear of bushings, hydroblock, pads of GDT, bearings of GDT reactor, oil pump, pressure drop and worn out packages, breakdowns of planetary gears start to show after 100-120 thousand km run. Even earlier in the case of some unicums.

It’s good that the Mohave was only fitted with the later versions of this automatic transmission, which are also configured for a very leisurely drive and an increased service life. The regulations stipulated oil replacement every 60,000 runs or even more often in difficult road conditions, and the automatic transmission cooling system is implemented “in the old way”, with a heat exchanger in a cold radiator tank, which for a diesel car is still an excellent solution.

As a result, up to 100-110 degrees ATF is heated only during long runs on the highway at high speed, and the installation of an additional radiator easily solves this problem (plus there are ways to reduce the operating temperature programmatically). So, with runs slightly over 100, the list of box problems is usually limited by wear of the Direct Clutch B drum, because the diesel torque is very high, and the car is heavy, and at swinging this drum is overloaded.

Sometimes one can also encounter with the wear of the separator plate because of overheats during long drives at high speed or “adventures” in the mud on the frame, and the aging of rubber hydro accumulators-fungi begins to show.

At 200-250 thousand mileages it starts to feel the wear of bushings, vibration of GDT and the related wear of oil pump bushing and wear of friction drums of Ovedrive E. Closer to 300 thousand it is almost inevitable a complete overhaul or replacement.

Front shock absorber.

The A8TR1 8-speed transmission, which Hyundai/Kia began installing from the end of 2011, as already mentioned, is similar to the ZF design in many ways, but it gets rid of many shortcomings. These 8-speed boxes work without full lockup only on the start, and the “almost full” lockup mode is eliminated due to the presence of a torsional vibration damper in the GDT. Five solenoids out of eleven are of classic design, they can be replaced completely without any consequences, and also they are more solid in electrical parts, unlike ZF solenoids which are afraid of even static. And, the most important, the company promised 8 years warranty for these boxes, which in our difficult times is a very good help.

It could not do completely without disadvantages: the pads of interlocking GDT wear out with frequent starts with a pedal to the floor more than with ZF. There are cars with 120-150 thousand mileages with friction locks worn out to a glue layer, with a clogged hydro-block and a dead pump.

The material of hydroblock plate is weaker than in latest ZF, that is why it sometimes gets scuffed. Mostly the accumulator channels suffer, they accumulate debris and rub the seats. As a result the accumulator pistons wear out faster and faster, but it’s very easy to remove outright scuffing here. But it is much more difficult to restore the kicked channel of the linear pressure control valve.

Mechanically there are no surprises, there are boxes with “trolleybus” howling – the first versions show wear of satellites axles. Unfortunately, the terms of regulation oil replacement are shifted up to 80 thousand runs, and this automatic transmission obviously likes clean oil.

The general verdict: the box is more successful, than the 6-speed, and with the excellent long warranty. But one should not consider it as unbreakable and on this basis to refuse service. Moreover, the warranty can be refused, for example, because of twisted mileage or overrun between service intervals.

Five-speed Jatco A5SR2, which can be found on isolated copies, is of earlier generation. There are simple interchangeable solenoids, simple locking algorithms, and the automatic control unit is outside. As a result, the box runs quite steadily for at least 150-200 thousand until the first repairs, and the owner has twice as much.

The reasons for the appearance of problems are usually several. The weak pad of interlocking of GDT does not like hard starts and quickly wears out to the adhesive layer. If you abuse it, you may face vibrations and overheating of traction converter with mileage up to 50 thousand, the oil will be polluted and the oil pump bushing will be worn out.

The second problem is the deterioration of friction clutches and brake band at mileages under 200 thousand or active pedaling. The friction clutch engagement time is delayed to ensure smooth operation under heavy load, and the clutches are actively worn out. The first to suffer is the Input Clutch package or the Direct Clutch package.

Wear and tear of solenoids is also an issue – with contaminated oil it happens rather quickly, so you need to check the oil condition at every service. And faulty solenoids easily lead to mechanical problems. The transmission can easily demonstrate miracles of life of quiet drivers: there are examples of runs up to 500 thousand without repair.

 

All-wheel drive

All-wheel drive is realized with the help of BorgWarner transfer case with front axle clutch and downshift gear. The system is quite “thoughtful” – unlike Haldex clutches it works slowly, with a delay. But it is rather reliable and does not require frequent oil changes. It is necessary to watch the work of motor for shifting modes, it usually suffers because of moisture in the connector and corrosion, and in the end the motor from within rots, and it is expensive. Friction and chain last up to runs over 250 thousand, if not to abuse lack of roads and sometimes to change oil in the aggregate.

By the way, there is one interesting variant of off-road tuning on Mohave. Since the box is compatible with BW with differential inside, the enthusiasts have already been able to install its analog with permanent all-wheel drive from SsangYong instead of transfer case with clutch “on demand” with replacement of only the rear cardan shaft. I’ll remind, the original four-wheel drive system has a weak spot in the form of ABS system sensors and weak wiring, with an error in them the car turns into reverse drive, so for jeepers such modification is quite justified.

Engines
Common problems

Spacious engine compartment and excessive radiator area, and at the same time simple and resourceful cooling system and intake pipes allow you to have a minimum of problems with the engines and their maintenance. Even the supports last a long time. True, all engines don’t tolerate the slightest decrease of antifreeze level in the system, and its leakage at engines with kolhozno preheater installed or, for example, as a result of radiator damage on lack of roads, occurs.

Gasoline engines

Can not find the V8 from KIA in Russia, but the V6 3.8 G6DA is on sale. The engine is not the best, you can see a brief description of its problems in the review of KIA Sorento. With mileage over 200 thousand, it no longer pleased with the wear of the piston group and oil consumption, phasor regulators knock, intake manifold breakdowns and leaks. On a heavy SUV, it gives neither dynamics, nor economy. It’s doubtful that it will turn out cheaper to run than the diesel 3.0. And there is a clear shortage among contract units, a clear sign of a failed engine.

Diesel engines

The bulk of the Mohave is equipped with 3.0 CRDi diesel engines from the D6EA and D6EB series. For all the similarity in characteristics, they differ greatly in details: they have different cylinder heads, glow plugs, fuel system, injectors, EGR and many other elements. The newer version, logically, meets more recent environmental standards.

In general, the 3-liter diesel is very successful. Many sources confidently call it a reinforced version of the Isuzu DMAX 6DE1, but in fact this assumption is a fabrication. The engines have a different design of the cylinder block, a completely different cylinder head, different timing, and the fuel system is fundamentally different. Only the volume and configuration coincide, and there is something common in the construction of the front wall of the block.

It has solid cast iron block without problematic liners, chain timing with 250-300 thousand kilometers service life, Bosch fuel equipment and BorgWarner BV50 turbine.

The list of problems is rather short. Glow plug power unit failures are common, and oil appetite is usually due to either a faulty crankcase ventilation system valve or turbine life. It’s best to replace the valve every 30-40 thousand miles, and problems with it will be indicated by oil on the spigot behind the turbo.

The turbine does not die all of a sudden, but it starts to leak oil into the inlet little by little early – by 130-150 thousandths. Fortunately it is conveniently installed, you can check for backlash and for oiling.

The turbine on the D6EB engines is slightly different, but with the same cartridge, but its resource has been increased to confident 200. The price of the cartridge is ridiculous 120 euros, so the replacement is not ruinous. Electric actuator drive of VGT variable geometry actuator serves reliably at least up to 150 thousand kilometers. Often the death of the turbine is due to its failure and regular overblowing.

Another reason of overblowing is not good sensors of absolute pressure. They get contaminated with soot and understate the readings. They are easy to remove and clean with carbcleaner, they are right on top of the intake manifold. Is it better not to use strongly aggressive liquids. The cause of the intensive formation of soot is the EGR valve operation. There is no particulate filter here, so the intake gets heavily contaminated. The valve itself is almost unbreakable, but if you want to turn it off, you have to sew the control unit, it has a multi-level check of the system operability. Reward will be about 300 hp and 650 Nm of torque on the firmware “for Euro-1”, favourite by tuners. The engine after it is simply jet, but the automatic transmission hardly digests such traction.

In diesel, there is also a mass air flow sensor (DMRV), it often gets dirty too, but it is on the conscience of the rare replacement of the filter and crankcase ventilation valve – when it is aging, the traction decreases greatly and there is a smoke at a low load.

The resource of timing chain is high, tensioners are inexpensive, and everything is arranged simply. It’s a pity, at 250-300 runs the chain can slip a little bit, in addition to the noise. Usually without serious consequences, only with strong loss of traction and smokiness, but from time to time there is also breakage of valves.

To take or not to take?

The Mohave is the case, when it is possible to take any modification. You will hardly find unfortunate petrol V6, and it is not necessary to cut off all the rest – yes, the restyled cars with an 8-speed gearbox are better from all points of view, but also the “pre-rest” one cannot be called so unfortunate. In general, the fact that the “absolutely new” Mojave 2020 in fact is an old model with new plumage, it is more likely to be written down in the list of its merits, rather than on the contrary.

 

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