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Land Rover Service Tips•About Range Rover air suspension ( EAS ) Oil and fluid recommendations We are a Mobil dealer, so we recommend Mobil products as a rule. However, our advise regarding weights and usage applies to any good brand of oil — Castrol, Amsoil, Texaco, Shell, etc. Read about why we like synthetic lubricants.Gas V8 engine and 300 diesels • Arctic conditions - Mobil 1 0-40• Normal conditions - Mobil 1 10-30 • Tropical conditions - Mobil 1 15-50 • Engines with oil leakage troubles - Mobil Delvac 15-40
Suspension on the new Land Rovers — About Range Rover EAS — Electronic Air Suspension Beginning in 1993, Land Rover began fitting EAS — Electronic Air Suspension to its top line Range Rover models. The system replaces conventional coil springs with air bags. The intent was to provide ease of access by lowering the vehicle for entry and exit, and better handling at high speed by dropping the vehicle down at speed while not compromising ground clearance by rising at low speeds.All County LWB models sold in the United States were fitted with EAS. Most 1995 Classic models, and some 1993 and 1994 Range Rover models had EAS as well. Since 1995, all 4.0se and 4.6hse models have an updated version of EAS. How it works: Range Rover air suspension have a height button (up/down) on the dash, and an inhibit button on the dash.Range Rovers have five pre-programmed height settings: Complaints that the air suspension does not respond to a new driver are usually a result of not knowing those three pre-conditions for operation. From a stop, pressing the down button will put the truck in ACCESS height. This is a very low setting, near the bump stops. It's meant to allow people to get in and out more easily. As soon as you drive off the truck will automatically rise to STANDARD height. From a stop, pressing the up button once will take you up one step in height, from ACCESS to STANDARD, or from STANDARD to HIGH. Two presses will take you from ACCESS to HIGH. HIGH is meant to allow extra clearance for wading a flooded road, crossing a log, etc. As with ACCESS, once you attain a speed of 20MPH the truck will automatically return to STANDARD. If you are in HIGH and you dangle a wheel in a deep ditch, the truck will sense that condition and put the one wheel into EXTENDED mode, where more air is put into the bag to press it to the ground. EXTENDED will release once the truck is level. Once the truck is on the highway it will drop to HIGHWAY profile, which is between STANDARD and ACCESS. It will drop after 2 miles at 60MPH and rise again to STANDARD after ½ mile at low speed. Theory of operation: Range Rover EAS consists of these major components:
Air is released through a muffler into the air, and when additional air is needed is it taken from the storage tank under the vehicle. The storage tank is kept charged by the compressor. Since the compressor starts and stops based upon the pressure in the storage tank its operation may or may not coincide with leveling of the truck. There are five sets of target height stored in memory, for each of the five height modes. Target heights may be programmed via the Testbook system. Some users may want heights that differ from the standard Land Rover targets, and it is sometimes necessary to correct the targets to compensate for different readings from the height sensors. Such differences may occur, for example, after collision repair if linkage pieces are bent and not replaced. Normally, the height sensors do not require adjustment or calibration. On a newer (4.0 or 4.6) truck parts can generally be replaced without the need to change programmed heights. The ECU evaluates each of the four height signals in the context of the other three to determine if each sensor is providing a valid signal. If the ECU determines that any one sensor is not providing a valid signal it will continue to level the truck using the remaining three sensors and set an EAS fault code. Failure of both sensors on either the front or rear axle will cause the EAS computer to deflate the system to the bump stops until repaired. The air suspension will level the vehicle when it is parked, but it will shut down after a period of time. Therefore, if the truck has any air leaks the driver may return to find one or more corners have sagged. Normally the truck will rise using the stored air in the tank as soon as it is started. Common problems: The most common EAS problems are leaking and dry rotted air bags, and damaged height sensors. The bags begin to leak at 100,000 miles or 6 years of age in most climates. The sensors get damaged by winter salt intrusion in snow country, and by being pulled beyond their travel limits when the wheels are dangled.Lifting the car on service lifts that dangle the axles can damage the air bags. When lifting a Rover on such a lift pay attention that the air bags do not pull away from the end caps and deflate. If they do, you will have to carefully guide them back together and hope the system re-inflates on startup. Otherwise, you'll need a Testbook reset. Classic models have a disable switch under the right front seat that should always be switched off before lifting. Opening a door slightly in a 4.0 or 4.6 will disable that system. In Classic models, most failures result in the vehicle dropping to the bump stops and staying there until the system is reset with the Testbook. Even if a repair is made the system will not return to functionality until reset. 4.0 and 4.6 models are much more forgiving. They are less likely to drop to the bump stops but they can be problematic just the same. Neither system can be repaired without the Testbook or equivalent specialist tool. There is no way to retrieve fault codes without this tool. As a result, drivers in remote areas often convert to coil springs. In cold climates the valve blocks are prone to freeze. Compressors also wear out as the vehicles age. Compressor wear can be judged by measuring the time required to pump up the air tank. The EAS computer monitors this and will set a compressor failure fault in extreme cases. Service options: The air suspension fitted to 1995-2002 Range Rovers is quite a bit better than that fitted to County LWB models, but those trucks are getting older and the systems are now beginning to give trouble.The most common problem is deflation when the car is parked. You leave the truck parked overnight and come out to find one corner flat, or even the whole truck flat. Most times you start it and the system rises to height, but one day it stays flat and you get a failure message on the dash. Another problem is air bags coming apart when the car is picked up on a lift. If this happens try and seat the bag carefully as the truck is lowered and it should re-inflate normally. If not, you''re in trouble, as the Testbook will be needed to reset it. At Robison Service, we offer two options: repair of the standard air suspension, or conversion to coil springs. Users in the field cannot generally repair air suspension because the system cannot be reset to function in most cases without the specialist test system (Testbook, Autologic or Rovacomm). For do-it-yourself repair conversion is really the only option. The air suspension can be fixed but you need to consider the value the system has to you versus its cost. As of this writing, January 2003, we can covert a truck to coil springs for a total price of $1,500. Repair of the air suspension may cost less initially but the long-term cost will he higher. The air bags have a service life of about 6 years or 100,000 miles before they dry rot and leak. A set of bags will cost a bit over $1,000 installed. In addition to the bags you have a compressor that wears our, and four height sensors. Replace those parts and you'll be well over $2,000. Another consideration is access to service. If you drive an air suspension truck far into the woods and blow a bag, you're in big trouble! If you off-road we suggest being prepared by carrying wood blocks to prop the suspension up to get home. In most cases, air suspension cannot be diagnosed or fixed without the $15,000 dedicated Land Rover test systems. You can change air bags on a working system yourself, but a failed system cannot generally be brought back to life without the tester even if you replace the necessary parts. The coil spring kits can be installed in the field if needed. The newest kits include a box that tricks the EAS computer and prevents warning lights from coming on. When we change to springs we often upgrade or replace the shocks at the same time. Depending upon what you choose for parts this can add $300-500 to the upgrade cost. Robison Service stocks spring conversion kits and several choices of shock. Climate control problems on the new Range Rover Many times climate control problems are indicated by the appearance of a notebook in the display window on the control panel. New Rover climate control systems have a pretty good self-diagnostic system built in. Unfortunately, you can’t tell what the problem is without the costly dedicated test system —Autologic or Testbook.The display unit is also the computer that runs the climate control system. With the exception of light bulb replacement it is not a serviceable piece. One common problem you can check yourself is the relays. Look in the relay box under the hood. In particular, look at the relays in the front for evidence of burning or brown spots on the case. Those relays power the fans, and they are prone to burn out and produce erratic operation. Another common problem is servo failure. Your Rover uses servo motors to mix hot and cold air to regulate temperature. A symptom of servo failure is one side of the car staying hot or cold while the other side regulates normally. Servo replacement is costly — near $900.  There is a small sensor on the heater pipe that senses temperature of water coming into the heater core. For some reason, this $30 sensor is prone to failure. At some point all new Rovers develop leaks from the heater core seal rings. Many folks confuse this with heater core leakage, which is very rare on these models. The o-rings seal the connection between the water pipes and the heater core. Replacement takes 3-4 hours with minimal parts cost. Symptoms are coolant smell in the car, wetness in the right side floor, and antifreeze drips behind the right front wheel. If you want to replace leaking o-rings yourself here’s how to do it. The o-rings are located between the pipe flange and the heater core face. The flanges are held together by a slide on collar secured by a concealed Phillips screw facing forward. Remove the glove box and glove box lock. Using an 18 inch ¼ drive extension with universal joint and Phillips bit, loosen the screw holding the o-rings by reaching through the glove box lock hole. You may have to saw through the plastic duct to the right side air vent. Use a hacksaw blade and repair with duct tape when done. You may want to glue the screw to the bit for re-installation. If your system drips water on your feet in summer try cleaning the drain tubes under the truck. On either side of the transmission there are tubes hanging down which you clean by poking a wire 1-2 feet up them. You'll get a gush of water if one was plugged and your drip problem will be solved. Robison Service performs all sorts of climate control repair. J E Robison Service Co Inc of Springfield, Massachusetts, is an independent business that specializes in the sale and service of used Land Rovers. We are not an authorized Land Rover dealership, we do not sell brand new Land Rovers and we are not otherwise affiliated with, originating from, sponsored by, or approved by Land Rover in any way.
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