KZJ nuances and reliability vs. HZJ

[classichead]

Hello folks. Been lurking for a bit but first time posting regarding taking the plunge in purchasing my first land cruiser. I originally had my heart set on a late 70's FJ40 due to its simplicity, but given I'm a bit of a stickler for originality vs. modifications; the lack of top speed and lack of ability to fit my family of 5 comfortably and safely in there has turned me away. After seeing both a HZJ77 and a KZJ78 Prado in person around town (Ohio) I've become a bit enamored with the 70 series. While a bit newer than my typical taste, it has the amenities that I'm sure my wife would enjoy and the highway cruising ability with a bit more modern safety features for the young kids fits the bill. Throw in most are RHD for a cool factor too. I'm looking for a manual transmission, reliable cruiser that I can drive multiple times per week that will not be used much if at all on the trails.

My question for the group is mainly around the reliability of the various versions. Based on my research it seems as if the 1HZ mated to the H55 manual transmission is the best combination with the 1KZ with indirect injection being good as well but having weaknesses with cracking heads and injector pump issues. My questions to the group are 1. What should I be looking for in the 1KZ to assess if the head and injector pump are in good condition? 2. What manual transmissions came with the KZJ70's? 3. Is a Prado SX the same as a KZJ?

Thanks in advance!

 

[AirheadNut]

The 1HZ/H55f combo is indeed one of the most reliable drivetrains available, but since it is naturally aspirated is also fairly slow, especially if you intend to travel at higher altitudes or in hilly terrain. It can be turbo'd, but there is potential for it to have the same reliability concerns as the 1KZ-TE, i.e. overheating, head or precup cracking.

The 1KZ-TE can be very reliable if the proper modifications are done. The injection pump is not any more prone to failure than any other 30+ year old diesel injection pump. One of the more common failures is the ECU: the capacitors inside start to leak and fail. Luckily, there are several places here in the US that will re-cap an ECU. The most important thing with the 1KZ-TE is to make sure the cooling system is in excellent condition, and a close second to that would be to install an intercooler.

For your stated use, I would recommend looking for a KZJ78. The coil suspension will be much nicer to live with in a daily driver and the smaller, turbo diesel engine will feel quicker around town and get the same or better mileage. In addition, the KZJ is geared higher than the HZJ, making it a better highway cruiser.

The manual transmission that came in the LJ and KZJ Prados is the R150f and R151f, the same transmission that was used in the 80's and 90's V6 4Runner, T100 and Pickup. It was also later used in the HZJ7x LandCruisers from 1999 onwards.

 

[WildSouth]

Eeeeverybody fails to mention injector servicing/replacement on 1KZ-TE's. People harp on and on about making sure the cooling system is in excellent condition (which I don't disagree with), but more importantly make sure the injectors have been replaced on schedule. If in doubt, get the inspected.

 

[sleepydad69]

Hello folks. Been lurking for a bit but first time posting regarding taking the plunge in purchasing my first land cruiser. I originally had my heart set on a late 70's FJ40 due to its simplicity, but given I'm a bit of a stickler for originality vs. modifications; the lack of top speed and lack of ability to fit my family of 5 comfortably and safely in there has turned me away. After seeing both a HZJ77 and a KZJ78 Prado in person around town (Ohio) I've become a bit enamored with the 70 series. While a bit newer than my typical taste, it has the amenities that I'm sure my wife would enjoy and the highway cruising ability with a bit more modern safety features for the young kids fits the bill. Throw in most are RHD for a cool factor too. I'm looking for a manual transmission, reliable cruiser that I can drive multiple times per week that will not be used much if at all on the trails.

My question for the group is mainly around the reliability of the various versions. Based on my research it seems as if the 1HZ mated to the H55 manual transmission is the best combination with the 1KZ with indirect injection being good as well but having weaknesses with cracking heads and injector pump issues. My questions to the group are 1. What should I be looking for in the 1KZ to assess if the head and injector pump are in good condition? 2. What manual transmissions came with the KZJ70's? 3. Is a Prado SX the same as a KZJ?

Thanks in advance!

I would second the KZJ78, I own a HZJ77HV. it's slow, rides like a board and is noisy. I love it, however... my wife thinks it's stupid thing. so your wife might react the same way?

 

[AirheadNut]

Eeeeverybody fails to mention injector servicing/replacement on 1KZ-TE's. People harp on and on about making sure the cooling system is in excellent condition (which I don't disagree with), but more importantly make sure the injectors have been replaced on schedule. If in doubt, get the inspected.

Excellent point. Honestly, checking injector health should be on the short list for any old diesel. Luckily with the IDI engines it is fairly simple to do.

 

[classichead]

Thanks for the quick insights all! A quick youtube search shows that the pulling of the injectors for cleaning or replacement is a pretty straightforward job as I'm fairly mechanically inclined. Does anyone know how difficult or expensive it would be to install an intercooler on the 1kz?

 

[flx]

the lack of top speed

Just to clarify on this point, a FJ40 (particularly with a 3.70 diff) is able to sustain higher highway speed than a KZJ7* or HZJ7*, all day long.

Now, any 70 series will feel a lot more confortable and safer than a 40 series on highway. But as for raw engine capability to drive fast on highway without blowing up F > 1KZ > 1HZ.

If this top speed is an important factor for you and as "efficiency" was never mentioned on this thread, a petrol 70 series may be a good option also...

 

[joekatana]

Just to clarify on this point, a FJ40 (particularly with a 3.70 diff) is able to sustain higher highway speed than a KZJ7* or HZJ7*, all day long.

Now, any 70 series will feel a lot more confortable and safer than a 40 series on highway. But as for raw engine capability to drive fast on highway without blowing up F > 1KZ > 1HZ.

If this top speed is an important factor for you and as "efficiency" was never mentioned on this thread, a petrol 70 series may be a good option also...

It seems that in every European country there are one or two guys that feel that the gas engines are faster mostly based on the rareness and the want of said rareness . I call utter bs on this on and I had a FJ80 here with a carbed 3F H150 and at the same time a HZJ80 with the 1HZ H150 and even though both are painfully slow I would pick the 1HZ all day , if you slap a sniper on the carbed 3F that changes things but then you can add a turbo IC to the 1HZ to level the playing field again.

The KZJ will feel more alive and my suggestion is look for a lhd without the problematic smog equipment on the jdm models and a manual trans , down the road you can always ad a IC or do some other mods if you need more power but no one is buying a cruiser for speed

If you buy a HZJ77 with a 1HZ/H55 it will be pretty much a forever truck as they are hard to kill

 

[Tierra Lodo]

Hello folks. Been lurking for a bit but first time posting regarding taking the plunge in purchasing my first land cruiser. I originally had my heart set on a late 70's FJ40 due to its simplicity, but given I'm a bit of a stickler for originality vs. modifications; the lack of top speed and lack of ability to fit my family of 5 comfortably and safely in there has turned me away. After seeing both a HZJ77 and a KZJ78 Prado in person around town (Ohio) I've become a bit enamored with the 70 series. While a bit newer than my typical taste, it has the amenities that I'm sure my wife would enjoy and the highway cruising ability with a bit more modern safety features for the young kids fits the bill. Throw in most are RHD for a cool factor too. I'm looking for a manual transmission, reliable cruiser that I can drive multiple times per week that will not be used much if at all on the trails.

My question for the group is mainly around the reliability of the various versions. Based on my research it seems as if the 1HZ mated to the H55 manual transmission is the best combination with the 1KZ with indirect injection being good as well but having weaknesses with cracking heads and injector pump issues. My questions to the group are 1. What should I be looking for in the 1KZ to assess if the head and injector pump are in good condition? 2. What manual transmissions came with the KZJ70's? 3. Is a Prado SX the same as a KZJ?

Thanks in advance!

78 Prados are really reliable like any other LC as long as you maintain it well. 1kz does heat up quick on steep hills with AC on, and 7 passengers inside. Just install good radiator and monitor your EGTs. It's a fun machine to own. Very capable too.