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The MQ Patrol is a fantastic 4wd for almost any requirement. They have been used and proven all around the world in roles such as daily drivers, competition trucks, fire trucks and they have even been used by armies!
Today, MQ/MKs still keep up with the latest 4wd’s off-road. Whilst they may not be as ‘flash’ and have all the gadgets and luxuries, they get the job done. The MQ is definitely a KISS car - “Keep it simple, Stupid!” - and it has a large and loyal following. Read some opinions here.
Simple mechanics and simple styling, what is not to like about an MQ Patrol?
- Cheap to buy
- Cheap to fix
- Easy to fix
- Very capable
- Strong drive-line
Don’t know anything about a MQ Patrol? This section will give you a quick and dirty overview.
The MQ Patrol was released in early 1980. The MQ is easily identified by its round headlights. It was available in a few body styles, including 2 door short wheel base (normally a 4 seater with removable canopy), 4 door long wheel base (5 seater van or 7 seater wagon) and utes.
3 engines were available; the L28 and P40, which were straight 6 petrol engines, and the SD33, a straight 6 diesel engine. The L28 is very common and known for its high-revving abilities. The P40 is not very common, and compared to the L28 it is like a ‘big-block’, making large amounts of torque at low RPM. The SD33 is a strong engine, with heaps of torque, but a little lacking in power. All the engines are very reliable if serviced and maintained regularly, and will do hundreds of thousands of kilometers.
The standard gearbox was the 4 speed manual. An automatic was available in L28 LWB only. All vehicles featured disc brake front and drum brakes on the rear. Manual steering was the standard, but power steering was available. Other optional extras included air conditioning, suspension seats, swing-away spare wheel and jerry-can holder, and the wide wheel pack (with steel flares). There were also a few different trim levels, mainly a budget version with vinyl floors, or the deluxe version with carpet floors. They were available in brown or blue.
The MQ Patrol was updated in late 1983. This ‘series-2’ vehicle is often called the MK. It is identified by its rectangular headlights.
The MK bought numerous beneficial changes with it, such as improved suspension components and self adjusting drum-brakes. The SD33 was available with a turbo (the SD33T) and was also changed to a common 12 volt electrical system. This engine has gained a bit of a cult following, as it has ample power and loads of torque and can be easily modified. The 4 speed gearbox was also updated, and now featured an overdrive 5th gear. This greatly improved fuel economy and top speed.
As a result of the updates, the MK is definitely more desirable than an MQ, and often fetch higher $$$. Most parts are interchangeable though, so it is common to find an MQ that has been upgraded with a SD33T and 5 speed. The MK was discontinued in late 1987, when it was replaced by the GQ (Y60) Patrol in Australia and other parts of the world. In European countries, the MK lived on and was further updated, including new engines. This model is known as the 260 Patrol.
Things to Thoroughly Inspect
It is easy when buying a car, especially one of this vintage, to get caught up in the moment and end up buying a dud. It is best to spend a good deal of time thoroughly inspecting the vehicle, so you know what your getting yourself into. This way, you can save yourself from (or at least prepare for) unexpected breakages in the future. This section will prepare you with a good game plan for inspecting an MQ/MK, and give you a heads-up on some common problems.
It is recommended to buy an MQ that has the engine in it that you want. Converting petrol to diesel is not an easy proposition, requiring new engine and gearbox mounts on the chassis, as well as exhaust, drive-shaft and wiring changes. It is possible, but hardly worth the hassle.
Many MQ Patrols around the world have received engine conversions over the years. Common in Australia is to find a Patrol with Chev, Holden or Ford V8. If you are going to purchase a car with an engine conversion, you should check that it is all permitted, for peace of mind. Also pay extra attention to the engine and gearbox mounts, to make sure that no dodgy work has been performed. Other than that, the following tips should still apply.
It is recommended to begin an inspection with the engine off and cool. This can provide great incite into the condition and quality of the engine.
With The Engine Off
Remove the dipstick and inspect the oil. It should be black (or golden-brown if its very new), any other color could indicate head or gasket problems. If the oil is low, this could indicate a neglected engine or a leak. Visually inspect the oil filter, if it is old and worn, this could also indicate a neglected engine. Remove the rocker cover cap and look inside, it should be very clean. Any sludge type buildup indicates the engine has not been maintained.
If it is a diesel, it is important they are regularly serviced (every 5,000km). If the oil is low or the oil filter appears very old (look for change at x km stickers for clues), this could indicate a neglected engine. Ask the seller how regular they have serviced the vehicle, but don’t forget it is easy for anyone to say “oh yer, all the time”.
If the engine is cool, remove the radiator cap and inspect the contents. Also check the overflow container. If the cap is milky/oily, then there is head gasket problems. Check the quality and level of the fluid. If it is plain water, low on fluid, or very dirty, it is likely that little care has been given to the engine.
Lastly, inspect all the add-on components. For all engines, check the condition of the belts, inspect the air filter(s) and spin the fan by hand. Check the condition of the engine mounts, and inspect the engine for major leaks. For petrol engines, check the distributor, coil and leads all appear good condition.
With The Engine Running
For diesels, it is best to inspect them when they are cold, so that you can check how much smoke it blows on start-up. It is natural for a diesel to blow a little white smoke on start-up, but if it bellows smoke, this could indicate other (costly) problems, such as a dud turbo or worn out piston rings. If it has a fair amount of smoke that clears up after a minute or 2, this could indicate the glow plugs need replacing, which cost ~$100 for the set.
The turbo diesels are prone to exhaust manifold leaks. A leak will sound like a soft ticking noise, and you can often feel the exhaust escaping (and sometimes see ‘burnt’ areas on the head). People have found that aftermarket gaskets do not seal well, so a genuine gasket should be used. These cost ~$70.
Hopefully there will be no abnormal engine noises at this time. Any knocks/ticks could indicate serious internal problems. You should open the throttle a few times, both slowly and quickly, to ensure the engine revs up and down smoothly and consistently. Any issues at this time could indicate a dodgy fuel system (pump, carby, injector pump etc) or bad ignition system.
The engines in MQ Patrols are sufficiently powerful to keep up with traffic and do feel ‘lively’.
When driving, put the engine through its paces. Attempt the following;
- Hard and fast take offs
- Slow but high revving accelerations
- Quick and sudden decelerations
- Full throttle acceleration from cruising RPM
- Accelerate to a moderately high RPM (ie 3500 RPM in a petrol), maintain this for a few seconds, then accelerate some more.
These tests often reveal any flaws in an engine (which are usually associated with fuel or spark systems).
In a diesel, try watch for any exhaust smoke. Black smoke indicates the engine is over-fueled and not burning the diesel correctly. Blue smoke is bad and indicates burning engine oil, you do not want to see this! On a good running engine, there should be no smoke most of the time, though even the best engines often put out a little black when under hard load (ie accelerating up hill).
Gearbox / Transfer
The manual gearboxes and transfer are strong and rarely cause problems. They were after all designed in the Nissan truck factory, and are used in trucks like the Cabstar. Little is known of the automatics reliability off-road, however it is a standard Jatco transmission, as used in many vehicles like the Datsun 260z. It will easily handle a hot L28.
As previously mentioned, the MQ had a 4 speed manual and the MK was available with a 5 speed. The 5 speed is the preferred gearbox as it provides an overdrive gear (good for economy) and also has a lower first gear ratio (better for crawling). Vehicles with a 5 speed often fetch a higher price than similar spec 4 speed vehicles. It is advisable to purchase a 5 speed vehicle from the start. Converting a 4 to 5 speed is possible, and 5 speed gearboxes can be had for a few hundred dollars. However, it also requires different length drive-shafts and modified transfer to chassis mounts, hence it is easier to buy a 5 speed from the start. If you are purchasing a MQ that has been converted to 5 speed, check the transfer mounts for dodgy workmanship.
When driving the vehicle, check the gearbox changes gears smoothly (for auto, also pay attention to any slip between gears or convertor flaring). It should be reasonably quiet and not emit any whirring/crunching noises. When performing the acceleration tests on the engine, the gearbox should handle this no worries. If it jumps out of gear, this would indicate internal problems, likely due to abuse.
Similarly, check that the gearbox engages 4H, N and 4L correctly. Drive in these gears (off-road) for a brief period, to ensure there are no problems with the transfer gears.
The clutches are fairly robust, but old age and abuse will wear them away. A slipping clutch will be noticeable during the engine acceleration tests, especially during the roll-on test. You will know the clutch is slipping, as the engine revs will pickup rather quickly (‘flare’) but the vehicle will not feel like it is accelerating.
New clutches can be purchased for ~$500, including heavier duty models. A fair amount of work is required to change a clutch, but it is easily done at home. A workshop will likely charge hundreds of dollars to change the clutch for you, so consider this when you are purchasing.
You should also ensure the clutch operates smoothly. Lightly press the clutch pedal to engage the throwout bearing, then listen for any grinding noises. If this bearing needs replacing, it requires the same amount of work as changing the clutch (ie remove gearbox).
Within the engine bay, visually inspect the master cylinder (on the firewall) and the slave cylinder (on the bell-housing). Check for leaks or cracks. Also check the rubber hose that connects the two, as this can become brittle and leak. On vehicles with body lifts, this hose is often stretched so far that it may split. Replacement cylinders cost ~$100 each, and a new hose can cost $50.
Diff’s (and associated)
The differentials in the MQ are a strong and reliable units, when maintained. In fact, a derivative of the rear diff is still in use today in the GU Patrol.
You should start off by visually inspecting the diffs. There will not be much to see on the rear diff. Check around the diff centre for any leaks. Whilst a leak in the diff mating-face is easy to rectify, the gears could be damaged if the oil level has not been maintained. A leak from the pinion seal is quite time consuming to fix, and requires special tools.
The front diff is a bit more involved, and should be inspected closely. First, try push and pull on the top of the tyres. This will reveal any worn bearings, especially king-pin bearings. Next, head under the car and check for leaks around the diff centre (the same applies as the rear diff). Then check for sludge buildup at the ends of the diff, behind the wheels and around the ‘balls’. Excessive buildup indicates the wiper seals are worn and need replacing. It is also likely the inner oil seals are worn, which causes the oil to leak out of the diff centre and down the diff tubes, washing the grease out of the knuckles (balls). This can have many bad effects if not rectified quickly, such as worn CVs and bearings. New bearing and seal kits can be purchased for $200, and the job is easily performed at home.
If the car has manual hubs, ensure they engage smoothly. You should test drive the vehicle with the hubs locked, as long as the transfer is in 2H this will have no bad effects. Having the hubs locked will spin the CV’s, axles, diff centre and drive-shaft as you drive. If you cant take the vehicle off-road for a proper 4wd test, this is the next best thing, as you should be able to hear a damaged component. A damaged CV will sound like constant clicking. Aftermarket CV joints cost $50 each.
When driving, listen out for any clunks or grinding from the diffs, which likely indicates damaged gears or worn bearings in the rear diff. If it only clunks around corners, this would indicate damaged spider gears in the diff centre. Tired/worn-out diffs/gears often emit a constant humming noise, but do not confuse this with tyre tread noise. Secondhand diffs can be purchased rather cheap, often around $150.
Whilst your head is under the car, take a look at the drive-shafts. They should be in good condition, any knocks/dents can cause vibrations whilst driving.
Not a lot can be checked without removing the wheels and pulling down the brake components. A visual inspection of the disc rotors is worthwhile, as these are the most expensive component to replace. They should be relatively smooth, with no gouges. This would indicate the pads have worn down to the backing pads at some stage and damaged the discs surface.
Check the brake master cylinder on the firewall. Sometimes the seals within these can fail, so check that it is relatively clean and has no visible leaks/drips. Brake fluid acts as a paint stripper, so a leak can often be identified by pealing paint underneath the cylinder. Also remove the cap from the master cylinder and inspect the fluid. Low fluid in one or both sections of the canister would definitely indicate a leaking brake component. If the fluid is an extremely dark/dirty color, this would indicate the fluid has not been replaced in a long time, which can give some indication to the level of upkeep on the brake system.
When driving the vehicle, the brakes should work good. Whilst the brakes aren’t great by today’s standards, they do stop the vehicle in a respectable time/distance. Whilst braking, the brake pedal should not feel abnormal. If it pulses, this indicates warped rotors or drums. There should also be no squeals when braking.
When inspecting the front diff, also pay attention to the tie-rod (joins the wheels together). This can often be damaged/bent when 4wding. Also glance over the ball joints on the ends of all the rods. If any rubber boots have perished, the ball joint itself is probably not far from failure. You can grab the rods and twist them by hand, which will reveal any excessive slop.
When driving the car, the steering should be pretty direct. If it is twitchy, or the car always pulls to one side, this could indicate a bent rod, which puts the wheels out of correct alignment. If the wheel turns more than 10 degrees without the car turning, this indicates worn ball joints or steering coupling (which is in the engine bay). A secondhand tie-rod can be purchased rather cheap. Replacement ball joints vary in price, but average $90 each. A similar problem also occurs if the leaf packs are worn and ‘fanning apart’, or bushes/shackles are worn, whereby the wheels can feel like they are wandering when you go around corners. New leafs will cost hundreds of dollars.
Wobbles Whilst Driving
This is a big problem with the MQ Patrol, and it is always associated with a worn out component. Often the wheel and king-pin bearings wear out, and allow the road-wheel to shake around on the end of the diff, causing the front end and steering wheel to wobble, often violently. Usually this happens at speed (like 60-80km/hr for example), but in extreme cases the wobbles can start at any speed. Sometimes the steering/car will wobble at all speeds. Other parts of the vehicle can cause this, such as damaged/unbalanced tyres, worn suspension bushes (as discussed above) and broken spring to chassis mounts. If you experience wobbles whilst test-driving, it pays to check out these areas for clues.
If the first thing you plan to do to your new car is give it a 2” lift kit, then its not really worth checking out the suspension. A lift kit will often include new springs, shocks and all bushings, so everything that may be worn out will be replaced.
If you are going to keep the current suspension, then check out each corner, 1 by 1. The leaves should look in good condition, and also be a nice continuous U shape. If they are worn, they will deform into a W shape. The front springs can suffer some damage off-road, so check around the front for breaks or fractures. If you are buying a car that has had a rough life, check that nothing dodgy has been performed to it such as welding broken springs back together.
Check all the bushes, as these perish with age. These include in the spring eyes, the ends of the shackles and even the ends of the shock absorbers. Also cast your eye over the shocks, as rocks often damage the tubes and reduce their functionality. You can try pushing down on each corner of the car, and watching the reaction. If it bounces multiple times, the shocks are likely worn.
Rust is a big problem on the MQ Patrol, and every car will have some hiding somewhere. No area is safe from rust, so check thoroughly. Also be on the lookout for dodgy rust repairs with lots of bod.
The most common rust areas include;
- The gutters (above the doors, along the sides of the roof).
- The lower portions of the doors.
- The sills, under the doors.
- Around the front windscreen.
- The area between the bonnet and the windscreen, which often rusts through into the cab and causes leaks.
- The top of the firewall (often due to the above).
- Around the radiator, especially the ‘bulge’ near the transmission mount.
- The lower portions of the rear quarter panels.
- The floor, the two most common spots here being
- Underneath, around the body mounts.
- Under the carpet, at the ends of the cross-members the seats bolt to.
In some extreme cases, the chassis can also succumb to rust. The most common area is towards the rear at the round cross-member above the fuel tank.
There is a lot to check when purchasing a car, and some of it is a bit basic and too general for this article (such as checking lights/electrics and tyres). Here is a quick list of other problem areas you might like to check;
- Door hinges start to sag.
- The little triangle windows on the front doors leak due to the rubber perishing and the metal channel rusting.
- Tailgate locks stop working correctly.
- Tailgate window struts loose their charge and do not support the window.
- The springs in the seats give way, front and rear.
- Seat belts may be frayed and not retract properly.
- Bonnet release cable may stretch and not open the latch sufficiently.
- Indicators do not cancel correctly.
On the older 24 volt diesels, it is important that the batteries are identical, else there will be charging issues.