This is gonna be a longer and somewhat thourough article so brace yourself !
First of all lets briefly check out 2 high mileage examples, since it’s gonna (maybe) help to make a better picture of these cars before we get to the more serious stuff.
595 000 mi / 957 000 km
HERE is an article about a 2004 Land Cruiser Prado with the 161 hp 3.0 D4D diesel engine with almost 600 000 mi. The car has a 5 speed automatic gearbox and the optional air suspension on the rear axle.
If you can’t open the article here are the things which were replaced on this car:
- injectors after 60 000 mi
- rear suspension air struts
- air suspension air compressor
- alternator (a few times)
- the multimedia system broke but was repaired
- regular maintenance items (batteries, brakes, wheel bearings)
- currently the AC is not working
service is carried out every 10 000 mi-oil change and filters, and the timing belt is replaced every 60 000 mi
the car has original engine and gearbox
484 000 mi / 779 000 km
HERE is an article about a 2008 Land Cruiser Prado with the 170 hp 3.0 D4D diesel engine with almost 484 000 mi. The car has a 6 speed manual gearbox and a standard coilover suspension.
If you can’t open the article here are the things which were replaced on this car:
- injectors under warranty
- drivers airbag squib (the component that sets the airbag off)
- windscreen wiper linkage
- starter motor
- brake calipers
- regular maintenance items (battery, brakes, wheel bearing)
service is carried out every 10 000 mi-oil change and filters, and the timing belt is replaced every 60 000 mi + gearbox and differential fluids are replaced every 95 000 mi + the owner never lets it idle for long periods when warm
the car has original engine and gearbox, clutch and turbo
So as you can see the 3rd generation Toyota Land Cruiser Prado – a.k.a. the Land cruiser 120 is capable of reaching very high mileage without much issues. There is no doubt about that. If you need a comfortable well-built off road car and you don’t want the legendary bigger Land Cruiser, then this really is a great choice. And according to those 2 examples it has bulletproof reliability !!
But is it really that straightforward? Well, not really. While it’s true that the petrol engines in these cars are great and reliable, the diesel engines can have a couple of issues which can destroy them. So let’s check them out more closely!
Believe it or not, this Toyota was available with 3 types of 3.0l 4 cylinder diesel engines:
The 5L-E is very simple and very reliable, but it doesn’t have a turbocharger so it has that much power as a retired snail smoking weeeeed, and it’s so rare, that even I’m not sure if it was really available in these cars (it was, they say). So let’s just move onto the other slightly more popular engine – the 1KZ-TE.
This 1KZ is not that powerful either, but it’s generally speaking reliable without unexpected issues. However if you manage to overheat it – then you will end up with a cracked cylinder head, so make sure that the cooling system of the engine is working properly:
- check for coolant leaks
- check the viscous fan hub/fan clutch which can fail (video about fan hub issues)
- check the radiator if it’s not clogged
- it’s better to not tow very heavy stuff or don’t push the car very hard in hot weather
(cracked cylinder head symptoms: coolant loss without visible leak, oil in the coolant, bubbles in the coolant overflow tank, overheating, white gunk under the oil cap, steam from the exhaust)
Also if you change the oil in this engine every 8 000 km / 5 000 mi then you will maximize the lifetime of the mechanical components a.k.a. the engine is gonna live forever with this oil change interval (until you overheat it). Before buying it’s good to rev the engine and check for smoke from the exhaust – if you see smoke from exhaust during acceleration then most probably the injectors are already worn out, so occasionally it’s good to replace them-like every 300 000 km to keep the good efficiency and performance of the engine.
This is the newer, most known and most common engine which can have various power outputs: 120 KW, 122 KW, 127 KW. It has an iron cylinder block, an aluminum cylinder head, 1 turbocharger, common rail injection and a timing belt. All of this sounds ok. And actually, I can’t say that this engine would be bad, since all the main mechanical components can withstand more than 500 000 km without much wear. Well, except maybe the pistons? Yes, those pistons… Once upon a time in the year 2006 Toyota slightly upgraded these engines to comply with the EURO 4 emission standards, and they also got new pistons! But let’s not overtake the things, because there are also the injectors!
INJECTOR SEATS LEAKING
First thing first, I have to mention the metallic sealing washers under the injectors. These washers can and they will leak at some point. This is not good since in this case → carbon soot contaminates the engine oil → this soot will clog the oil pickup strainer restricting the flow of oil → which will cause oil starvation → which will kill the engine if you don’t catch it early enough!!!!! That’s why the most important is to: check the oil pick up strainer every oil change – which is easy, since after you remove the oil drain plug you will see at least part of the strainer – and if it’s clogged or not.
So you should definitely check the strainer right after buying and every oil change + if you want to be very thorough, you can buy a small endoscopic camera and use that to check the whole oil strainer thru the oil drain hole.
Symptoms of leaking injector washers:
- clogged oil pickup strainer
- louder knocking noise from engine after cold start
- white/grey smoke from the exhaust at first engine start – when the engine is cold
“replacing all the injector washers + all the required seals can cost approx.: $560 (if you want to have the injectors tested too → and you should, then keep another approx.: $300 for the testing)”
This issue affects mostly cars made to 2007 since Toyota used weaker injector washers in these cars which can easily leak before 200 000 km (there have been numerous cases of total engine failures because of this issue in these 2007 and older cars with less than 200 000 km). But from 2008 Toyota updated the washers + in some countries there was also a recall for this. So the good thing is: plenty of these cars do have the updated better washers already fitted. But the bad thing is: in many countries there was no recall so there are still cars equipped with the weaker washers-mainly lower mileage cars with less than 200 000 – 150 000 km, and even the updated washers are not gonna last forever! That’s why it’s good to replace these washers preventively mainly on these cars made to 2007 if you don’t have a proof that they were replaced in the past.
Why is it a good idea to preventively replace the injector washers?
The problem can be if the previous owner replaced the injectors and he either re-used the old washers or if he used aftermarket washers which can fail prematurely. So always use genuine injector washers! Now you can ask, how often you should replace these washers? Well, nobody knows when exactly these washers are gonna fail! The genuine updated washers can easily last way over 200 000 km, but as with the injectors it’s good to consider replacing them preventively. The interesting thing is that the service manual says that: you should check the valve clearances on this engine every 40 000 km. During this procedure you have to remove the injectors as well, and if you remove them then you automatically have to replace the already mentioned washers+seals on the injectors. Now, if someone removed the injectors in the past and re-used the old washers then obviously they are gonna fail prematurely. This valve clearance measuring procedure requires some disassembling, so it’s not the cheapest and that’s why I don’t think many of the owners actually do check the valve clearance every 40 000 km. On the other side, the valve clearances are usually fine at 100 000 or 150 000 km and even after that the valve clearance can be just a little bit out of spec. So checking the valve clearance is most of the time not necessary this often.
ALL IN ALL: if everyone would follow the service manual to the last word and did the valve clearance check every 40 000 km then THERE WOULD BE NO ISSUES with the injectors washers like EVER, since they have to be replaced every time you take out the injectors!
“The worst combination is when the previous owner put bad quality or even used injectors in the engine in the past + he re-used the old washers or put bad type of aftermarket washers there! And this is why after buying a used 1KD engine you should preventively at least remove the injectors → have them tested even if they look fine → and replace the washers with the genuine Toyota washers! Of course if you want to spend the extra money then you can replace the injectors at the same time as well + while doing all this check the valve clearance and eventually adjust it. Obviously if you have a good proof that the previous owner already replaced the injectors and the injector washers with good quality parts, then you don’t have to do this.”
Fun fact: Toyota got rid of this issue only in the newer 150 models in 2015:
The 1GD 2.8 l diesel engine made from 2015 in LC150 has improved injector mounting – the injectors are more like externally mounted so the oil pickup strainer clogging issue is not common on these engines. It’s also because the injector rubber oil seal is mounted way upper on the injector so it’s more away from the heat-the lifetime of it is bigger, and if the washers on these injectors do start to leak, then the leak will be externally visible on the valve cover. But all in all, the injector washer lifetime should be similar on these engines too so they will last 200 000 km, but after this mileage point it’s better to replace them.
The next issue related to the injectors are the injectors themselves. They can fail even before 200 000 km and even on the newer land cruiser 150 equipped with this engine. How can they fail?
- they can be weak
- they can leak
- they can have bad spray pattern
Symptoms of bad injectors: rattling noise from engine, loss of power, jerking, limp mode-check engine light, smoke from exhaust when accelerating, bigger fuel consumption
But the worst thing is that they can cause wrong combustion. Wrong combustion… keep this in mind since you will hear it later. Anyway, if you got one of the symptoms of bad injectors, then have the injectors at least tested or replace them + if your car has more than 200 000 km then it’s a very good idea to replace the injectors preventively if you want them to be reliable, efficient, and to perform as they should!
Some owners are replacing the injectors preventively every 130 000 km, 100 000 km or 150 000 km. Some mechanics recommend replacing them preventively every 100 000 km, but to be honest – this is just wasting. The most optimal is to replace them every 200 000 km with new genuine washers of course, and check the oil pan pickup screen for debris every oil change + monitor your car for weird behavior which can indicate issues with injectors like: light grey or white smoke from the exhaust, strange fuel consumption rising, jerking while driving, or bigger rattling noise from engine.
To be honest, most of these cars already have more than 200 000 km so it’s definitely a good idea to replace the injectors preventively, and if you buy a car with 300 000 km or with 400 000 km then there really is nothing to talk about. And yes, the injectors can last 300 000 km or 400 000 km but if you want them to be reliable, efficient, and to perform as they should – then replace them preventively. But of course if you want to leave the injectors there for a longer time it’s fine-it’s your choice, and maybe you will be lucky to experience no issues with them. However just keep in mind, that after 200 000 km the performance of the injectors is gonna be much weaker than it should be + the spray pattern is not gonna be great at all either + there is a higher chance that they will fail – like for example start to drip fuel.
on the next page: PISTON CRACK + BONUS ISSUES