5.7 fouling plugs?

[bloc]

The 5.7 used in the Cruisers have different SQCs, usually known to be MR imaged for cracks after cast settling. But the problem of having issues starting sometime after having after market exhaust components is quite common, definitely starts with o2 sensor reading deviations. But I have read a couple of successful replacement with Tundra 5.7s in the 200 forum and a certain classified who replaced the whole engine with a used one.

What is SQC in this context?

 

[RyanArcane]

What is SQC in this context?

Sorry should have elaborated Statistical Quality Control.

 

[bloc]

Sorry should have elaborated Statistical Quality Control.

Thanks.
So that means cruiser/LX 3URs are objectively built to a higher standard than for tundra/sequoia?

 

[RyanArcane]

Thanks.
So that means cruiser/LX 3URs are objectively built to a higher standard than for tundra/sequoia?

At least the casting process of the blocks are set to better sigma levels. Other parts of the assembly technically should be too. But that I couldn't verify. I know that the LC does share the same problems of Cam Tower leaks and the timing cover leaks and occasional blown head gasket but one can argue that is attributable to design flaw. It's a bit difficult to compare the real world results of the SQC given the skew in the number of Tundra Sequoia's around. But bottom up the LC's 5.7 does have pretty stringent Quality Control.

 

[bloc]

At least the casting process of the blocks are set to better sigma levels. Other parts of the assembly technically should be too. But that I couldn't verify. I know that the LC does share the same problems of Cam Tower leaks and the timing cover leaks and occasional blown head gasket but one can argue that is attributable to design flaw. It's a bit difficult to compare the real world results of the SQC given the skew in the number of Tundra Sequoia's around. But bottom up the LC's 5.7 does have pretty stringent Quality Control.

Any idea whether this concept applies to other complex parts such as the transmission?

 

[Bunga]

Edited for accuracy. I was thinking of the Tundra...

 

[Cruisin911]

The LX parts are assembled by Japanese vs. Americans.

If this is assuming the the LX is Japanese built and the LC is American built, this is incorrect information. The LCs are built in their own factory in Japan. The LX is not special in this regard.

 

[RyanArcane]

If this is assuming the the LX is Japanese built and the LC is American built, this is incorrect information. The LCs are built in their own factory in Japan. The LX is not special in this regard.

This is incorrect as far as the 200 series is concerned, they both used to be made in both Yoshiwara and Tahara both in Japan. Now I think there is some news of LCs being built solely in Tahara and LX s in Yoshiwara respectively. Check this post Quality differences between Yoshiwara and Tahara? - https://forum.ih8mud.com/threads/quality-differences-between-yoshiwara-and-tahara.972638/

Both have pretty high standards of finish.

 

[RyanArcane]

Any idea whether this concept applies to other complex parts such as the transmission?

I know for a fact the differences start from the design itself both top down and bottom up as in the design of component placements and overall design start with the acute direction of 25 year service life span. Bottom up being frame hardening, items like CVs and diffs etc. (just as an example) are built with that focus and attention. That is just the design part. I think a lot of these auto journalists cause these misconceptions since they say stuff like 'shares the platform with the Tundra'. And for the most part items are interchangeable but there are differences intrinsically on various levels starting right from design.


Toyota put a lot of rigorous test cases for scrutiny right down to the bolts, flanges, seals etc. (whether this is even more stringent for the Land Cruiser I couldn't find evidence). I know the parts that go into the vehicle at assembly have pretty high check rate at the Toyota side (again whether this rate is higher for the Land Cruiser compared to the Tundra I couldn't find info on that). From my experience most part numbers are different for items between the Tundra and the Landcruiser. I think it's highly possible that they are designed differently (not superior or inferior) and put through different test case checks and higher rate of check for standard requirement/100 items(might be more scrutiny for the LC parts). I think having the 25 year life cycle puts more stringent test case checks at every level. I could be wrong but corroborating such information with hard proof is a bit difficult without internal data.