Soon the great journey begins. Have you thought of everything? Passports, visas, tickets, equipment .. ? And also the vehicle should be checked, because no one wants to start with an unpleasant feeling. We have summarized what should be checked on the car before a longer trip in this guide to the vehicle check before the offroad trip.
A broken vehicle during the trip spoils the joy of traveling. In the worst case it ruins the whole trip. Of course, not all problems can be discovered on the vehicle before the trip, no one would disassemble the entire car including engine and transmission beforehand, but a vehicle check, in good time before the start of the trip, is still highly recommended.
We have compiled a vehicle check for you, which is especially intended for longer trips. If you are planning shorter journeys, you can reduce the points as required.
Another tip: do the vehicle check in pairs. This is faster, both get to know the car better and it’s more fun too. Allow a good 2 to 3 hours for a leisurely drive.
Vehicle check in the engine compartment
The first thing to do is of course to check all fluid levels. first from above, this concerns checking the engine oil, clutch and brake fluid and the power steering system. If, according to the maintenance manual, you are due to replace consumables now or in the near future, you should also do this before your trip. Remember to change also the affected filters. However, this should not be done the day before departure. Because if anything were to break or a defect were to be discovered, the start of the journey would have to be postponed so shortly before departure. So better plan time for touching up.
First, however, you should look for damp, oily spots in the engine compartment that indicate a loss of fluid. Take a good lamp and illuminate the engine once all around. Look thereby also into the angular corners. Especially you should look at the areas around the valve cover gasket, the cylinder head gasket, all hose connections, turbocharger and the filter.
In addition to checking the level of the brake fluid, you should also test the water content. For this purpose, there are simple testers that measure the electrical resistance of the liquid, which gives an indication of the water content. Too much water in the brake fluid can cause vapor bubbles during hard and long braking and consequently the brake pressure is lost.
The engine has at least one belt. Usually the cooling water pump, alternator and servo pump are operated via this belt. This also means that if there is a problem with the belt drive, the coolant pump and alternator will fail. If the car has additional units such as air conditioning or compressors, you will often find more belts. Each should be checked for its condition. It must be undamaged externally and must not have any transverse cracks or even broken-off parts.
Once the belt(s) are down, you can also check the idlers and tensioners. In particular, if you don’t always take care of your car, but are not afraid of mud and dirt, you should do this check. Dirt can get into the bearings of the rollers and over time it destroys the bearing until it eats and disintegrates completely. Then the pulley is loose or jammed. The consequences can be manifold. From a sudden engine stop at low speeds to a broken V-belt, many things are possible.
The rollers must rotate very easily without any noise. Try moving the roller, jerking it back and forth. There should be no play whatsoever. The lever arm of the tensioning pulley must move freely against and with the spring pressure.
If you have an engine with a timing belt, you should find out how often it needs to be replaced. If it is soon, have it changed before the trip. A ruptured timing belt is often accompanied by major damage to the engine.
If the V-belts are off, you have usually also removed the fan. Now you have a clear view of the radiator. You should visually inspect it to see whether it has any defective or dirty spots. If dry sludge is stuck between the fins, cooling performance is reduced. You can rinse out the sludge with a gentle jet of water.
The fin structure should be undamaged. Small areas where the fins are a little bent are not dramatic, but larger areas or badly bent areas should not be ignored. Here in our area, the cooling capacity may be sufficient, but depending on where the journey goes, it is no longer sufficient.
Check the antifreeze level
You can then test the antifreeze content in the coolant with an antifreeze tester, preferably a refractometer. Even if it’s not going to cold climates at all, the right amount of radiator antifreeze is important for the cooling system. There are lubricants and rust preventive additives, it prevents deposits and premature boiling of the water.
Check the hoses
Just like later under the car, you should also pay attention to the hoses from above for a moment. This includes the hoses of the cooling system, turbocharger, vents, air conditioner and servo. If there are other aggregates, such as an automatic sway bar, other hoses are added during the vehicle check before the trip. Even a visual inspection can reveal weak points. If hoses are already porous, hardened or have bulges and cracks, there is a risk that they will soon break down completely.
Turbocharger hoses may be undamaged externally, but the inner hose layer may be collapsed or already showing signs of detachment. So it’s worth looking at it from the inside as well. If there is also a lot of oil in the hose between the turbocharger and the engine intake manifold, there is a problem with the turbo. You can read more about this here: the turbo – avoiding damage.
Older turbochargers have a pneumatic-mechanical controlled bypass. This consists of a pressure can with a linkage. This must be free flowing. You will need some force to move the linkage as there is spring pressure on it, but it should move. If the mechanism is stuck, you will either have a loss of power or worse, creeping damage due to overspeeding. Read also our big article about problems with the turbocharger: the turbocharger – the diva of the engine.
Modern vehicles have turbochargers with variable geometry. The adjustment can also be pneumatic, i.e. by vacuum and spring pressure, or by an electric servomotor. If you have an actuator on the turbo, you have to disconnect the linkage from the actuator before the test and then it should be easy to move it. There is no spring pressure to overcome.
Vehicle check under the vehicle
Since you just came from the engine, you can continue right there under the vehicle. Look for oil drops and wet spots. Some hoses, like those of the cooling water or pressure hoses of the power steering, can only be seen properly from here. Check their condition. They should be dry and have no porous spots or even cracks.
After the engine, in the direction of the rear of the vehicle, the clutch bell follows. Often there is a small hole at the bottom, so that leaking oil does not collect in the bell. If oil comes out there, it is either engine oil coming from the shaft seal (simmering ring) of the crankshaft or it is gearbox oil that took its way past the leaky shaft seal of the gearbox inlet. But, liquids find strange ways, so fuel can appear there, for example. Either way, you should look for the leak and fix it.
Engine and gearbox bearings
The motor and the gearbox are suspended from the frame with rubber pads. These pads play a not insignificant role in comfort and the elimination of harmful vibrations. Finally, they also hold the whole system in place. And they are often neglected.
Before a long trip it is also necessary to check its condition. To do this, lift the engine and gearbox a little out of their bearings, for example with a gear jack or similar lifting device. Then you can look at the rubbers in compressed and extended condition.
Another suspension is that of the exhaust pipe. It also hangs in rubber to reduce noise and vibration. These are aging and tend to tear first and then through.
The fuel lines are also routed on the underside of the vehicle. A possibly installed additional filter is therefore usually also to be found there. These lines must be free of chafing. Look for places where pipes cross and touch each other. If possible change the. Maybe one of the lines just popped out of the clip.
Parallel to the fuel lines you should also check the brake lines. Are all pipes in good condition and rust-free?? What is the brake pad and brake disc thickness?? After all, you don’t want to have to replace something after a few kilometers on the road.
- Just like the rubber bushings of the trailing arm mount on the axles. They must be free of play, which you can check with a pry bar. Depending on the axle layout, you have two or four such trailing arms.
- The bearing heads and rubber bushings of the A-arm, if you have one.
Now that you have already checked the front axle, you can also check whether the axle joints are tight and filled with oil. Vehicles with permanent all-wheel drive have homokinetic joints on the steered wheels, which are located in the steering knuckle housings. There is a grease filling in there. Check the necessary filling level according to the manufacturer’s instructions and check whether the chrome surfaces of the steering knuckle housing show any damage, rust spots or severe scoring. All this will lead to leakage and break the seal ring. The chrome surface of the ball must be slightly greasy. Otherwise the seal and if necessary. The steering knuckle housing should also be replaced. If you lose oil there and do not notice it, it can cost you the homokineten.
Double is better
Another tip for land rover defender drivers: land rover used long double lip seals for the knuckle housing. The first lip pushes the dirt away, the second lip seals the seal. This will last long and well. On the last model years of the defender and if you have it repaired with the original land rover spare part, you will get a single lip seal. They do not last as long. Our recommendation is therefore to get a double-lipped seal in the spare parts market and have this installed.
On vehicles with selectable all-wheel drive, a universal joint is installed under a protective cap instead of a homokinetic joint with a steering knuckle housing. You must also check this for play and grease it if possible.
Shocks and springs
The dampers must not lose any oil, i.e. they must be dry. If you have dampers on the rear axle where the piston rod extends downwards, protective covers should be fitted over them. Otherwise flying stones can damage the chrome layer. These small damages make the seal of the damper broken.
The nuts of the damper must be tight, the rubber bearings must not be porous or cracked. The damper is mounted in a ball joint at the top, which should be free of play.
During the pre-trip vehicle check, you should check that your suspension springs are rust-free, show no damage and are seated in their plates. Often they have protective covers at their ends to protect them from damage and subsequent corrosion. If your chassis has spacers to increase the height, these must also be undamaged and in good condition.
Mostly under the vehicle and at the wheels, you check the drivetrain. This includes the clutch, the gearboxes, cardan shafts, differentials and the drivers on the wheels. If you do not have the appropriate experience, you should consult a specialist here. It is about detecting wear and excessive play in the driveline. The procedure may vary slightly. The specialist for your vehicle but takes into account the peculiarities.
What you can also test with less experience are the universal joints of the cardan shafts and the connection between the stub shaft and the driver on the wheels.
Cardan shaft joints
The universal joints of the cardan shafts are also part of the vehicle check. They are heavily stressed. They should always be rinsed and greased after an off-road trip. Of course, this also applies before you start your journey. First check the game, there must be none available. For this you have to twist the cardan shaft flange and the shaft to each other and move them in all directions to each other. In all four spherical plain bearings, the universal joint must not move.
You can see what cardan shaft play looks like here:
If everything is in order, grease the joints, unless they are maintenance-free and have a grease nipple. correctly, the cardan shaft should be removed, so that the grease really presses into all four spherical bearings.
With this we are done under the vehicle. You can determine the play between the axle shaft and the driver on the wheels, if your vehicle has this combination. The wheel must be raised and the shaft and driver must be visible. Now turn the wheel slightly back and forth. Wheel and shaft must move together without misalignment. Besides, everything should be well smeared with grease.
On vehicles with rigid axles, the adjustment options for the chassis geometry are very limited. Only the toe on the front axle can be adjusted. If this is not correct, the inside and outside of the tread will run unevenly. Sawtooth-like profiles are usually formed.
Further information on good travel preparation
In our series of articles on the right tools for traveling, you can read about what you should take with you on long trips.
In our little vehicle check before and after off-road driving, you’ll get tips on how to check your vehicle before and after off-road use.
If you want to travel around the world with a diesel vehicle, you can find more hints and tips in our article about the diesel engine on the road.