Main & Rod Bearing Spec

Can anyone with TIS access post this?

 

no

 

I can find the main clearances for the V35A that comes in the LS500, but the rods seem to be absent from their usual place in the manual.

 

That would be great if you can share, thank you!

 

Main journal 73.988 - 74.000

Clearance metric
Journals 1 & 4 .031 - .047 max .052
Journals 2 & 3 .035 - .053 max .058

Rod journal 55.392 - 55.400

No clearance given, will look further.

 

These clearances call for a 30W oil for temps up to 220F and 40W over 220F.

Given the undersqaure bore/stroke ratio, high torque and boost pressure, bearing issues could be here to stay if you are using 0W20 oil..........

 

Interesting, I wonder if switching to a 10w - 30 weight oil would be beneficial for longevity. The issue I can see going that route is the first 20K you are supposed to take the truck back for an oil change at the dealer who would use 0w-20. I supposed that could be negated by letting them change the oil there and promptly switching it out. It would an interesting experiment.

 

I have been running Shell Rotella T6 5W-40 since 1500 miles, last UOA was less than average wear.

Oil temps run around 220F driving up to 240F towing........

 

Now that is interesting. There is an oil analysis thread in here somewhere it would be interesting to see your results over the life of you engine vs someone who uses the 0w-20. How many miles do you have on your truck currently?

 

30K

 

It may be worth switching it out.

 

Be careful experimenting with oil viscosity

https://amsoil.co.in/what-happens-i...r oil doesn't,and harmful sludge and deposits.

 

Yes, I too thought it was interesting that the clearances are larger than even the UR Series V8…. Which ideally should really run a 5W30. Like most accidents and disasters, we’ll likely see a combination of factors that add up to a failure.

 

That is good information to have. Kind of makes the argument to switch to a 5w-30 more appealing over the use of 5w-40. Where I live, the chance for oil to get really thick and start having flow issues at the weights we are talking about is relatively low... Its hot here.

 

The question is: "Is Toyota specing a 0W20 for fuel economy at the expense of longevity"

The engineering requirement for oil viscosity to rod and main bearing clearances is not open to debate.

A decision to deviate is knowingly making a compromise; At cruise RPM and low load on the highway, running no boost, in cool climates, with frequent changes, no fuel dilution, oil temps @ or under 212F a 20W MIGHT be sufficient...........

 

I think the page got taken down in a purge, however, the international LC manual calls out multiple viscoities with 0w-20 being the ideal one.

However it shows you can run 5-20, 5-30 and 10-30(0F+)

0W20 called out for best fuel econ and cold-weather starting.

I would much rather run 5-30 in my engine, however, US manual doesnt call that out and if things blow up I really dont want to risk it with Toyota finding 5w-30 in my engine. (12/23 build)

 

The overseas LC300 with the V35A-FTS (Type '21) are seeing similar failures.

 

I think if it blows up there would be so much particulate in the oil you couldnt tell what viscosity it was.

 

Correct- however, this was to the point that 30 weight oils would be more than OK as discussed above and looks like the engine was designed for that initally.

 

5W-20 is perfectly ok in the Tundra/Sequoia.

 

I would rather throw 5w-30 in it than 5w-20- especially since the engine can tollerate it just fine. Again I just dont want to risk it with a blow-up.

 

The Tundra/Sequoia manuals specifically call out 5W-20 as being able to be used, so if you are wanting to use a thicker oil, 5W-20 fits the bill and the manual supports it.

 

5w is only thicker at startup temps. Operating temps it is just 20 weight oil. 5w-30 would be a thicker oil at operating temps.

 

One would think if viscosity was an issue it would surface in the other bearings as well?

 

this^

its not viscosity, if it were you would see a MASS of failures not a few compared to all the tundras and V35A on the road, remember, they have made 100's of thousands of these now.

 

So knowing the bearing clearances are 30/40 weight depending on temps who else is running heavier oils? I live in the mountains of Colorado and my oil temps consistently hit 220-230F going up mountain passes when the truck is empty. Granted my 35" wheels have something to do with it probably. The truck is a lot quieter with 5w30 in it all the way to redline verses the 0w20. I'm not going back after running 0w20 for over 30k.

 

In my previous Ecoboost Ford's, they called for 5W30 oil, which the Toyota engine is based on. Ask me how I know. Anyway, I routinely ran 10W30 and my Ecos liked it better. Quieter operation and no noticeable difference in fuel economy. I only have close to 12K miles on my Tundra, so I'll be switching to 5W30 oil at the next change. If it fails, it fails. But I highly doubt it will. I just believe with what I put my truck through, extreme heat here in Phx and towing, that the heavier oil will provide better protection. YMMV.

 

I would love to do 5W30, however, I dont want to jepordize warrnty and replacement issues in the future. At 61,000 i would make the switch.

Unless Toyota for the US states it is OK to run 5W30 like they do for the 300 series.

 

I towed for about 3 hours yesterday on the interstate, oil temps were 232-238F.

I wonder what the how thin a 20W would be at those temps..............?

 

I wonder if with the new short block part # 11400-F4020 addresses the issue?