Chevrolet Tahoe II

Looking ahead, I will say that the construction turned out to be very reliable. However, there are nuances, and a lot of them. 

The frame is less vulnerable to corrosion than in old Land Cruiser 100, which are much more expensive. The GMT800 platform, on which the Tahoe is based, does not represent anything particularly interesting. It is a very classic frame chassis with independent front suspension on double wishbones, non-split rear axle and torsions in the front suspension.

Motors - only V8, Vortec family: 4,8 LR4 and 5,3 LM7, although under the program of factory tuning dealers could order a set with Small Block 6,0, BigBlock 8,1, as well as with a diesel engine for 6,6 liters. The car was equipped with automatically connected all-wheel drive, so-called ToD (Torque on Demand) with transfer case NP246. 

Among the serial options there was an air suspension Autoride, and the interior - "full luxury": two air conditioners, two stoves, leather, a separate multimedia installation for the rear row with DVD-player, satellite radio, navigation, emergency communication system and remote diagnostics OnStar, automatically darkened exterior mirrors.

In the course of production the list of options was constantly supplemented, there were also technical updates. Thus, since 2002, the engines were able to be powered by biofuel E85, and since 2005, the engine cooling system was changed: electric fans appeared instead of viscous coupling in the fan drive.

At usual operation and moderate care you can not expect special problems with a frame, it is necessary only to take as a rule sometimes to wash it and to check points of fastening of a body, suspension and so on. Well and when choosing a car, pay the seller to wash the car from the bottom. In spite of all survivability, there are "dead" cars with a rotten frame - usually after heavy off-road use.

The body is large and iron. It rots quite moderately: fenders, doors and sills may be a little rusty, but this is rarely critical. But there is a catch in the form of large plastic covers, often hiding the true scale of the disaster. 

In favor of corrosion resistance is a decent thickness of metal and paint, but the design itself contributes to the accumulation of dirt in the most unexpected places: inside the wings, bumpers, sills and so on. One of the main "dirt collectors" is the towing hook beam and the spare tire elevator, which is suspended from below. The latter rusts by itself and pulls the metal of the underbody above it. Also pay attention to the rear arches (especially in the places of joints with the sills), the trunk floor and the same rear door.

The bumpers on the Tahoe are steel and chrome, like those on the related Silverado pickups. New they look luxurious, but with age they rust, and chrome fades.

Interior

Although, as it was already mentioned, the interior flaunts a mass of pleasant options, the trim itself is rather oaky, but reliable. The most unpleasant (and various) problems here are with climate control. The additional heater has long pipelines, and they are very vulnerable, as they are laid under the bottom and corrode. A similar story is with the rear air conditioner.

Fans of thermo-sensors of climatic are rather large and serve for a long time, but if they start to howl, they are very loud. And the worst thing is that actuators of climatic system are located in the bowels of the front panel, and it is very difficult and expensive to replace them. 

Temperature damper and outside air intake damper are souring: there are a lot of troubles from them, and it is not comfortable to drive with breakage. And lastly, the tees of the heating system in the underhood - one of the most demanded consumables for this model. Plastic parts are not distinguished by reliability and resource, they warp, crack and leak, and also they are broken by careless servicemen.

Acceleration sensors for airbags are also a consumable, they rust from inside and swell. Errors on airbags, which you can find at computer diagnostics, more often appear because of them than because of steering wheel loop breakages.  

Breakdowns of the rear seat frame occur quite often, the seats in this case do not move and do not change the angle of inclination. The front seats are more durable, but here it is mainly the lining materials that fail - the leather fades at mileage "over 300". 

If the window lifter does not work (do not forget to check everything all round), it can be either the wiring in the door or the mechanism itself, which with age clinks.

There are many complaints about the native multimedia: navigation, music, DVD and so on. If the car still has factory equipment, it may not work at all, but more often there are copies with third-party Chinese devices. They are head and shoulders ahead of the outdated equipment in terms of functionality (and often quality) - the main thing is that the installers have straight hands.

Electrics

Except for the mentioned problems of the interior, there are few difficulties here. Generators are quite reliable, power reserve is decent, but it is often difficult to find 160-amp models for postrestyling, and when repairing they put a cheap replacement for 90-110 A from pickup trucks.  For cars before restyling it is not so terrible, but on restyling there are electric fans of radiator cooling, and they need power very much.

The gasoline pump is at risk in case of mileage "over 200" and bad gasoline. It costs pennies, but it is difficult to replace it: you have to either remove the tank (with disassembly of the suspension) or saw a hatch in the body from above.

Do not spare money for computer diagnostics: it often finds errors on lambda probes and detonation sensors, which are not too reliable. Under-hood wiring and the "braid" on the ABS unit may be worn out. On cars with AutoRide pneumatics there are problems with pump life, but usually they are connected with air leaks, but not with the electrics and actuators. 

However, all these cases are infrequent. And if the interior was not flooded, and alarm system and non-native "music", mentioned in the previous section, were installed by masters with straight hands, the old Tahoe will rarely require visits to the electrician.

Brakes, Suspension and Steering

The braking system of the big "American" is characterized by high price of details and still seems weak against the background of powerful European crossovers. But at adequate style of movement pleases both resource and reliability.  

Only the above-mentioned ABS block (besides wiring, it suffers from dirt because of unsuccessful location), and also tubes do not please. They are heavily loaded here, have a considerable length and corrode. The hoses are composite, loaded no less, for obvious reasons they do not corrode, but they often leak. When repairing it is necessary to consider that it will be difficult to pump the system without dealer scanner, it will be necessary to help ABS block to expel air from the complex system of tubes.

Suspension of the car, as it was already mentioned, is simple: double levers in front and axle in the back.  Ball bearings in the front can be syringed, and steel arms are very reliable. Sometimes there are aluminum upper arms, as on Escalade, but by experience of masters, silent blocks in them are perfectly changed separately. 

The main problems of suspension are springs sagging, wear of shock absorbers and small compression strokes. So much so that sometimes the limiting bumpers in the front are simply "killed" from frequent impacts. The suspension mounts also rust badly, which is a hassle to repair. 

Torsions are used as elastic elements of the front suspension. They are quite reliable, but their adjustment limits are relatively small. The torsion beam has its own vibration isolating suspension, and you need to remember to change the silent blocks there. Torsion keys on older cars often don't provide the necessary range of adjustment to maintain standard ground clearance. But enthusiasts offer both tuning options and serial parts from related GMT800 platform models, which originally had a greater range of adjustment.

If there is AutoRide pneumatics at the rear, and diagnostics has shown that everything is good with wiring, you will have to remember how pneumatic hoses are organized, where pneumolines are, where compressor is, and why fittings flow. 

The steering gearbox is reliable, although with age it accumulates backlash and loses reactionary action. The steering trapezoid also has many parts and gradually accumulates backlash. On older cars, the main failures are related to incorrect reactive action on the steering wheel and pump howling. The former is treated only by a complete and thorough reassembly of the mechanism, including all elements of fastening to the frame and body (and it is expensive), and the latter - by changing the oil in time. 

Gearboxes

In the USA, rear-wheel drive Tahoe on MG5 mechanics can be found on sale. Native driveshafts go on 250-300 thousand, and if to take into account that almost all old Tahoe ran more, you can get ready for repairs. Fortunately, cross members and suspension bearing are changed separately without problems, and prices are quite reasonable.

The rear axle suffers mainly from gearbox leaks due to microcracks of the cover. The cover is best to change at the slightest suspicion of leaks. And when buying, check if the cracks from the screw holes to the edge of the sealant. The axle heats up a lot, and in case of freezing or contamination of the axle ventilation breather, oil simply squeezes out. Bearing damage in this case is usually fatal. The axle housing itself is quite strong - if you don't jump on stones, it is unlikely to be damaged.

At the front, the gearbox is made in an aluminum housing and is heavily loaded in most cars, where there is no separate 2H mode - only automatic all-wheel drive 4H. A regular nuisance is a clogged breather hose. It is led out into the under-hood space, but not very successfully: it can be flooded or simply blocked because of a bend. Accordingly, either water gets into the crankcase, or oil leaks through the oil seals.

The main pair is quite reliable, but the tapered bearings often require replacement when the mileage is under two hundred thousand. If the magnet in the crankcase has grown a "hedgehog", then urgently to service, while the main pair, shafts and housing are intact. The bearings themselves are inexpensive, and to pick them up is not a problem. 

Front axle ball joints are quite strong, the resource at careful operation - "for 250", but standard individually joints are not changed, only a set, and they are not budget. It is possible to pick up the parts, but in our country it is a rare standard size, it will be necessary to order from the sites in the USA. At mileage over 300 thousand you can meet gearboxes with worn out seating places of oil seals on the shafts. Usually more frequent oil seal replacement will save the situation, but sometimes polishing the surface and installing non-native sized oil seals is required. 

In most cases there is a chain NP246 with ToD system - automatic connection of the front axle through frictions with hydraulic drive and electric actuator in the drive.

The transfer case life is quite long with timely oil change. At mileage of 250-300 thousand you will often need a rebuild kit of bearings and seals numbered AE TK-246, or just a set of gaskets K105-946. The HV-063 chain may need replacing sooner - it depends on the load. The pump and frictions are very durable, just don't forget to change the oil. 

The main volume of breakdowns is provided by the actuator. It is weak, it has a weak motor, weak gearbox and leaky connectors.  Until 2005, the actuator 600-901 was used, after that - 600-812-R. They are not cheap, so if only the motor needs to be repaired, or the gearbox needs to be restored, and the housing is still intact, it is often cheaper to repair rather than replace it. You can order some parts from America, and if you can't, you should know that you can buy a transfer case from Escalade - it has no reduction gear, but the price is two times lower.

It remains to add that on cars imported from the USA, in addition to the "usual" NP246 transfer case, there are absolutely other, exotic variants: for example, NV261C, NV263, severe T150, NV241C or NV149. We will not go into the details of the differences, just keep in mind that there are a lot of transfer cases, and it makes sense to specify the model before buying, so that then there were no problems with ordering spare parts.

Automatic transmissions

Mostly there are automatic transmissions of GM 4L60E series, and on cars with rare custom motors 6,0/8,1 and diesels 6,6, as well as on Heavy Duty variants for towing heavy trailers there are more powerful boxes, series 4L80E, even with a separate cooling radiator. All automatic transmissions are made by GM, with 4 stages, electronically controlled and forced locking of GDT. 

Designs are very reliable and time-tested. They do not like only dirty oil and high revolutions, due to the features of the used oil pump. And the oil is contaminated quite intensively, because the setting of torque converter lock (which lining is the main supplier of dirt) is quite aggressive.

We can not say that these boxes are "eternal", but with a quiet style of driving they can easily withstand more than 350 thousand mileage, and half a million are rolled up. But if you constantly stomp on the gas pedal and wear out the aforementioned GDT lock, be prepared for a much lower resource.

The main weak point of 4L60E boxes is package 3-4 disks. The box is so organized that wear of solenoids due to oil contamination leads to lack of pressure to engage third gear and bump when engaging fourth gear.  For fans of sharp acceleration and overtaking, it is recommended to install Kevlar friction disks - for example, one-sided Raybestos Z pak. On the contrary, for maximum resource in quiet highway operation, it is better to leave the standard paper ones, they pollute the oil less.  

The load on the brake belt and Reverse Input drum is still high. Traces of tape burning can be clearly seen on the drum in the form of a black ring - shocks during downshifts are usually caused by this problem.

And a typical jerk or even a bump on startup, at shift 1-2 - this is quite a typical failure of the hydraulic block, prepare a set of Sonnax HP-4L60E-01. Pump usually try to replace with a newer, reinforced at any repair: so all resource problems are less noticeable. 

If you drive long and hard with shocks in the box, then usually the case of the rear planetary gear does not withstand - it twists and tears, after which the box gets up finally. Surprisingly, but even after such failures, repairs usually cost less than a hundred thousand: thanks to a huge fleet of cars with this transmission and the low price of new and used parts.  

"Heavy Duty" box 4L80E is much stronger in construction, and 5.3 motors do not cause any problems to it. However, even a giant 8.1 will not scare it. Unlike the "younger" series, here among possible resource problems are only two brake belts after 250-300 thousand kilometers and solenoids every 200 thousand or even less often. Dirty oil and high load can lead to wear of bushings and Direct package, but usually it happens at very high mileage - more than half a million. 

These boxes will easily outlast the entire car. If possible, order this particular automatic transmission for replacement in case of a serious breakdown of the 4L60E. True, the dynamics with it will be worse: it is configured more conservatively.

Engines

The main motor on the Chevrolet Tahoe II is a 5.3 Small Block of the third generation (indexes LM7 and L59), much rarer are cars with a 4.8 LR4 motor. Even rarer are the 6.0 LQ4/LQ9 motors. These are all variations of the same small-block. In general, the 4.8 differs from the 5.3 only in piston stroke, and the 5.3 variations have fuel system differences. 

You can determine what kind of motor was on the car from birth by the eighth symbol in the VIN number: if V, then it is the weakest motor 4.8, if T, then LM7, and if Z, then L59 with FlexFuel. If suddenly you have N or U, it means that the owner has ordered an exclusive variant with 6.0 engine.

You won't guess the actual engine model under the hood: they look almost identical. In addition to reading the engine number, you can also look into the cylinder through the plug hole with an endoscope: the 4.8 has a flat piston, while the 5.3 has a displacer. 

The block is always cast iron, the cylinder head is aluminum, injection is distributed, and ignition is separate modules with short wires. The camshaft here is a single camshaft in the block camber, with no phase shifter, and the timing drive is a short chain with no tensioner.

The design, provided more or less decent operation without frank dirt on the inlet or overheating, can go 500 thousand without any intervention, and if you managed to wear it out, the pistons and crankshaft have repair sizes. 

It's also very easy to assemble and disassemble. There are even contests for speedy assembly. These guys, for example, managed to do it in 17 minutes.

Getting back to the real world perspective, overheating should not be considered something unbelievable. The cooling system suffers from leaks (most often from plastic tees), and the pump is not eternal. 

Just don't put any gas equipment on it. Or be prepared for the valve seats to fall out, or the valves to crack in half, after which the motor will successfully destroy itself. This happens on gasoline, but much less often.

Also, if you turn the engine hard, the pushrods in the timing gear can wear out. In any case, when buying it is recommended to evaluate their ends for changes in geometry.

In addition to leaks of antifreeze, there are also oil leaks. For example, from the "cup" of the dipstick, pallet gasket or oil filter bracket. And the sump may leak not because of the old gasket, but because the bolts are banal rotted. 

The tank ventilation system gives out a bunch of errors, and due to American tradition, the error on the ventilation system reduces engine power.  Any leaks, a loose plug, a vent carelessly filled with gasoline, or just an old adsorber is a serious problem. 

Conclusion

If it were not for the Americans' desire for high power figures, the car named in honor of a beautiful lake would probably eclipse the Toyota Land Cruiser 100 in popularity in our country. After all, the body of the "American" by corrosion resistance, perhaps, surpasses the Japanese, motors are not less reliable and much easier to repair, and the transmission is only a little more troublesome.

It is quite possible to take an old Tahoe, keeping in mind not only expenses on taxes and fuel (although with quiet driving it is possible to keep consumption within 16-18 liters), but also probable investments in auxiliary systems. And, of course, remember that any reliable construction can be spoiled by a careless approach to its operation.