Was the 2UZ-FE an improvement on the 1FZ-FE?

[SaturnAscends]

Now 2 x 2UZs + A750 with 1,000, 000 miles (1.6M kms). Having had both, 2UZ for me...

Million mile Tundra 1
Million mile Tundra 2

I remember when the FZJ80 was released with the mighty 4.5 litre inline 6, Toyota's ads pointed to it being able to be bored 30 thou' up to 3 times.

Oh and fuel consumption?

Yeah Toyota said it should be rebuilt every 200k miles or so at least twice. With a 2UZ it seems like basic maintenance is all that's required to make it to that 600k mile mark. Around 200k the 1FZ will at the very least start leaking fro the valve stem seals.

Funny how different countries have different views on the same things. Here in Oz I reckon a knowledgeable jury would side with the 1FZ over the 2UZ for reliability and longevity.

IMO, while the V8 rumble is great, and no doubt the 2UZ with A750 is much nicer to drive, I'd feel much more comfortable driving an FZJ80 with manual transmission into a war zone than I would a 100 series V8 Auto

I wanna Australian 1FZs were more reliable due to the lack of EGR etc., especially the later coilpack ones we never got.

Remember he didn't ask about "better", he asked about durable and reliable. Better is highly subjective, subject to individual opinion. It's possible that 2UZ is more durable, that is long lived, but it's a close call. The 1FZs are awfully stout and the later ones seem to be less prone to head gasket problems. They are both so long lived that it may be too soon to be asking the question. Let's wait a couple more decades.

But on the subject of reliability I don't think the 1FZ can be beat. Modern electronics cause too many sudden inexplicable no-run failures, often resulting in a tow. 1FZs limp so well. Engine reliability has to be considered in the context of the electronics that make them go down the road. If your ECU fails or your VSC system is braking on one side of the vehicle and running you off the road there's little consolation in knowing that your head gasket is solid. Your modern engine is a co-conspirator in the problem. Modern electronics are not without compromise and are generally shortening the useful and economic life of automobiles.

How common are these electrical failures on the 100s though? And the FZJ80 isn't immune to electrical issues either. If you really wanna avoid that you'd have to get an old 1HZ-powered Cruiser or something with mechanical injection.

 

[Zjohnsonua]

TL; DR: Is the 2UZ-FE a more durable and reliable engine than the 1FZ, all else being equal in terms of age, miles, maintenance, etc.? Why or why not?

Thank you for reading.

Both are very good engines when maintained. They both have their shortcomings when they're neglected. When I ditched my 2F I went back and forth between the FZ and the UZ. I went with UZ due to parts availability and low end power.

 

[beatle_bayly]

Oh and fuel consumption?

FZJ80 fuel consumption is akin to 'fight club'........

 

[jsloden]

My 2uz is currently sitting at 443k miles without ever being torn into for anything other timing belts. I owned 2 fzj80's before this. One of them needed the head gasket at 210k. The other one had 190k and I didn't feel comfortable taking it on long trips because I knew it hadn't been done. I feel completely comfortable taking my 100 series anywhere without issue. It also tows a lot better.

 

[Devils Paw 80]

I wanna Australian 1FZs were more reliable due to the lack of EGR etc., especially the later coilpack ones we never got.

It's easy enough to delete the EGR, if your state allows it. Ignition problems don't seem to be an issue with the non coilpack FZ engines we got in the states.

The FZ remained the engine of choice in the 70 series abroad until 2009, when it was replaced by the 4.0 Toyota V-6.

With the very large 100 series, a V-8 is a more appropriately sized powerplant, especially for America's go fast customers.

As others have stated, clearly they're both very reliable engines.

The Toyota V-8 is a high tech marvel, though likely more difficult and expensive for the home/shadetree mechanic to work on compared to the heritage I-6 engines.. Will it go for more hundreds of thousands of miles without major issues? Based on what we've read on MUD it sure looks that way. Less oil leaks to fix? No doubt.

So to answer your question, the UZ seems to be an improvement in both durability and reliability.

Would I prefer owning a 100 to an 80? Not really, otherwise I would. How about you, the consideration of purchasing a 100 prompted the question?

 

[SaturnAscends]

It's easy enough to delete the EGR, if your state allows it. Ignition problems don't seem to be an issue with the non coilpack FZ engines we got in the states.

The FZ remained the engine of choice in the 70 series abroad until 2009, when it was replaced by the 4.0 Toyota V-6.

With the very large 100 series, a V-8 is a more appropriately sized powerplant, especially for America's go fast customers.

As others have stated, clearly they're both very reliable engines.

The Toyota V-8 is a high tech marvel, though likely more difficult and expensive for the home/shadetree mechanic to work on compared to the heritage I-6 engines.. Will it go for more hundreds of thousands of miles without major issues? Based on what we've read on MUD it sure looks that way. Less oil leaks to fix? No doubt.

So to answer your question, the UZ seems to be an improvement in both durability and reliability.

Would I prefer owning a 100 to an 80? Not really, otherwise I would. How about you, the consideration of purchasing a 100 prompted the question?

I’ve been considering a GX actually at some point in the near future, or possibly a J100 if the right deal comes up.

It does hurt to lose the solid front axle and shade tree serviceability and simplicity, but the 4.7 trucks so seem easier to live with day to day.

I will always miss my 80 series though.

 

[Coupedncal]

Though 1UR-FE (4.6L from the GX) was never introduced in North America for the LC / LX models, what is the general consensus on that model compared to the other two models being discussed here? Is it about even in durability and reliability? The 1UR-FE also has a timing chain so no timing belt to switch out and that should give it an edge over its predecessors.

 

[Zjohnsonua]

Though 1UR-FE (4.6L from the GX) was never introduced in North America for the LC / LX models, what is the general consensus on that model compared to the other two models being discussed here? Is it about even in durability and reliability? The 1UR-FE also has a timing chain so no timing belt to switch out and that should give it an edge over its predecessors.

The UR is setting up to be a very good engine. It has it's own problems though, namely the cam tower leaks - which are more of a hassle to fix than most are willing to deal with.

 

[saucebox]

I’ve been considering a GX actually at some point in the near future, or possibly a J100 if the right deal comes up.

It does hurt to lose the solid front axle and shade tree serviceability and simplicity, but the 4.7 trucks so seem easier to live with day to day.

I will always miss my 80 series though.

Losses can be accounted for

(but the 80 is still a superior front axle setup)

 

[NE Snowman]

I wouldn’t be scared of taking my 2UZ anywhere in America, neither leak or have ever done anything other than what they’re supposed to do, turn on point and go.

Only things replaced are maintenance stuff, Tbelt/water pump @ 90k and 180k I replaced all the bearings and moving parts that touch the Tbelt / serp belt. Cams still didn’t leak at 230k so not ripping the VVTI open for that until it’s leaking.

My wife wants a 200 (08-11)because they’re close to price vs well maintained 100s (06-07) and have new tech. I’m not sold on a 3UR yet though so…Hundy please

 

[Njck22]

Though 1UR-FE (4.6L from the GX) was never introduced in North America for the LC / LX models, what is the general consensus on that model compared to the other two models being discussed here? Is it about even in durability and reliability? The 1UR-FE also has a timing chain so no timing belt to switch out and that should give it an edge over its predecessors.

UR series had different design goals. High power, efficiency, light weight. Obviously very reliable but not as “bulletproof” as a 2uz. It uses an aluminum block, with iron liners and it runs nowhere near as smooth as a 2uz, yet gets the same or greater mileage while producing 50% more power. It’s also considerably more intricate.

 

[newbielx470]

I wonder how much more money we actually need to spend for the timing belt change aspect, given that many other parts can get replaced while-in-there. Those parts (or similar parts) need to be changed for timing-chain engine also, right? And also timing chain probably won't last forever and need service at some point too...

So maybe we only spend a few hundred $ more per every 100k miles for the timing belt engine compared to timing chain engine (only considering this aspect)?

 

[NE Snowman]

UR series had different design goals. High power, efficiency, light weight. Obviously very reliable but not as “bulletproof” as a 2uz. It uses an aluminum block, with iron liners and it runs nowhere near as smooth as a 2uz, yet gets the same or greater mileage while producing 50% more power. It’s also considerably more intricate.

Yes it’s amazing how much more power the UR has, but I don’t tow much so I’m a smooth/bulletproof guy.

 

[NE Snowman]

I wonder how much more money we actually need to spend for the timing belt change aspect, given that many other parts can get replaced while-in-there. Those parts (or similar parts) need to be changed for timing-chain engine also, right? And also timing chain probably won't last forever and need service at some point too...

So maybe we only spend a few hundred $ more per 100k miles for the timing belt engine compared to timing chain engine?

I don’t think the belt is a big deal at all. And yeah once you go in twice around 180-200k I’d replace most of the moving parts while your in there. Unless you don’t mind fixing them as they break.

The 1GRE? (6 cyl in tacos and 4 runners) local shop has had to replace 2 chains before 160k, both had stretch and one has a bad sensor as well. Most also know they have head gasket problems.

 

[SaturnAscends]

I wonder how much more money we actually need to spend for the timing belt change aspect, given that many other parts can get replaced while-in-there. Those parts (or similar parts) need to be changed for timing-chain engine also, right? And also timing chain probably won't last forever and need service at some point too...

So maybe we only spend a few hundred $ more per every 100k miles for the timing belt engine compared to timing chain engine (only considering this aspect)?

The 1FZ timing chain seems pretty solid. You don’t hear of many failures. The water pumps on the 1FZ also seem incredibly robust; I’ve heard of them lasting for 500,000 miles. On the UZ and especially the later UR engines, the water pumps don’t seem to last nearly as long. I’m not sure why that is exactly.

 

[western flyer]

I owned, drove, and worked on both for over a decade each (sample size of 1 each...) The 1FZ is an obviously older, less efficient design and generally more stoutly built IMO. The 2UZ was smoother, less NVH, and more pleasant to drive, more power, etc. I enjoy working on the 1FZ. I never enjoyed working on the 2UZ. The 2UZ is more like a car motor (as noted above, Lexus LS...), the 1FZ is more like a 4wd truck motor. When super remote in Baja I would rather have the 1FZ for peace of mind (reliability and ease of repair). While cruising around the US I would rather have the 2UZ. All that being said, an 80 series with a new 2UZ would be a nice rig.

 

[Stylo07]

The 1FE has its roots in post-WW2 Chevy inline 6s.

The 2UZ has its roots in the $1bn LS400 project.

Yes the 2UZ is better.

Sorry to blow the dust off this thread — I just couldn’t leave the first sentence in the above quote alone without addressing/correcting it for future readers. Also, I realize this is probably a dead and bloody horse.

The F Series (think 40, 50, and 60 series Land Cruisers), NOT the 1FZ-FE (think 80 series, as well as 70 and 100 series (105 series)), has roots in a Chevy six. The 1FZ-FE is a clean-sheet Toyota design, one that I doubt was inexpensive to complete.

That said, having owned and read up on both, I think they’re something of an apples-to-oranges comparison.

On paper, they’re both good designs. Yes, the 2UZ-FE is related to the almighty 1UZ-FE, but it doesn’t have the six-bolt main bearing caps of the 1UZ-FE or the beefy(er) forged rods of the early 1UZ-FEs. The 2UZ-FE, however, does not seem to suffer in these areas. The 1FZ-FE is inherently strong with its seven-main-bearing bottom end that’s common to many straight sixes.

Despite the above differences, both engines seem to see a relatively low percentage of bottom end failures. Therefore, I would say the bottom ends of both engines are not a factor of longevity or durability.

At the end of the day, if I were asked to pick which engine sitting on a dyno stand at 4K rpm for 100k miles would yield the least leaks and repair needs, I would choose the 2UZ-FE.

 

[beatle_bayly]

At the end of the day, if I were asked to pick which engine sitting on a dyno stand at 4K rpm for 100k miles would yield the least leaks and repair needs, I would choose the 2UZ-FE.

I've had two 1FZ-Fe's over 12 years of ownership and I'd guess they've spent a total of one minute in total at or above 4000rpm

 

[SaturnAscends]

I've had two 1FZ-Fe's over 12 years of ownership and I'd guess they've spent a total of one minute in total at or above 4000rpm

I needed 4,000 RPMs to maintain speed up most sustained grades in my FZJ80, with the trans in second.

 

[SaturnAscends]

Sorry to blow the dust off this thread — I just couldn’t leave the first sentence in the above quote alone without addressing/correcting it for future readers. Also, I realize this is probably a dead and bloody horse.

The F Series (think 40, 50, and 60 series Land Cruisers), NOT the 1FZ-FE (think 80 series, as well as 70 and 100 series (105 series)), has roots in a Chevy six. The 1FZ-FE is a clean-sheet Toyota design, one that I doubt was inexpensive to complete.

That said, having owned and read up on both, I think they’re something of an apples-to-oranges comparison.

On paper, they’re both good designs. Yes, the 2UZ-FE is related to the almighty 1UZ-FE, but it doesn’t have the six-bolt main bearing caps of the 1UZ-FE or the beefy(er) forged rods of the early 1UZ-FEs. The 2UZ-FE, however, does not seem to suffer in these areas. The 1FZ-FE is inherently strong with its seven-main-bearing bottom end that’s common to many straight sixes.

Despite the above differences, both engines seem to see a relatively low percentage of bottom end failures. Therefore, I would say the bottom ends of both engines are not a factor of longevity or durability.

At the end of the day, if I were asked to pick which engine sitting on a dyno stand at 4K rpm for 100k miles would yield the least leaks and repair needs, I would choose the 2UZ-FE.

I wonder why Toyota insisted on an iron block for the 2UZ, but then have it weaker conrods. Iron blocks might technically be stronger, but only if you’re making crazy power.