Put wrong viscosity in my Tundra truck. Forget about it?

   / Put wrong viscosity in my Tundra truck. Forget about it? #51  
Further, the whole "tight tolerances" thing is largely hogwash.

So Computer Numerically Controlled (CNC) milling isn't better than "Bubba's eyeball"? Guess again. One case in point I read awhile back was the Evinrude outboard motor of today, about the only 2 cycle that competes in a 4 cycle market. Tours of the factory revealed that their machining tolerances are not 0.001 (a thousandth of an inch) but 0.0001 (a tenthousandth of an inch).

My 2009 Ram Hemi P/U's owner's manual specifically said that the oil pump in the engine was designed for 5W-20 and that if you used a heavier oil it could impede the ability of the engine to do the cylinder drop economy function.

So much for SWAGS!
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #52  
I wasn't talking about production tolerances, I was referring to bearing clearances. Production tolerances on most Japanese engines were and still are very good, the U.S. stuff has gotten better but still catching up.

When you machine engines back to back on a cnc machining center you get a pretty good idea on who's machining is consistent.

On the other hand, tighter production tolerances also means more consistent bearing clearances with less need for heavier oils to compensate for variations.

You said "tighter tolerances" now you're clarifying that it was bearing clearances....okay, as I said, the two aren't the same.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #53  
Actually I referenced both in my original post, and clarified how tighter tolerances are relevant in my last post.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #54  
So Computer Numerically Controlled (CNC) milling isn't better than "Bubba's eyeball"? Guess again. One case in point I read awhile back was the Evinrude outboard motor of today, about the only 2 cycle that competes in a 4 cycle market. Tours of the factory revealed that their machining tolerances are not 0.001 (a thousandth of an inch) but 0.0001 (a tenthousandth of an inch).

My 2009 Ram Hemi P/U's owner's manual specifically said that the oil pump in the engine was designed for 5W-20 and that if you used a heavier oil it could impede the ability of the engine to do the cylinder drop economy function.

So much for SWAGS!

I never said any of that. I said things like ideal bearing clearance gaps today aren't any tighter than they were many years ago. Production tolerances, meaning variation from ideal, has gotten better but that's largely a different topic.

People keep saying "tighter tolerances" but they clearly don't understand the definition of the term.

We aren't talking about your 2009 Ram, we're talking about a Toyota Tundra. Toyota gives no similar warning about using heavier oil, and you might note that even Chrysler doesn't say it's going to damage the engine.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #55  
Actually I referenced both in my original post, and clarified how tighter tolerances are relevant in my last post.

No, you said: "the result is tighter bearing, pump, cam phasers etc. tolerances."

Bearing tolerances isn't bearing clearance/gap.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #56  
Please go back and read the first post you quoted, I said they have tightened up bearing clearances quite a bit.
As for tolerances having an affect, consider an engine that has a couple thou tolerance and one that is a couple tenth. Heavier weight higher cold flow numbers were necessary to compensate for the potential of larger bearing clearances.
Bearing clearances and tolerance are seperate things, but they do have an affect each other.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #57  
There was a time when all my vehicles took the same oil... The good old days LOL

Gosh, remember back when they all took 5 quarts of oil too?

Now, I have one that's 4.5, one that's 5, and one that's 6 quarts. All completely different viscosity's.

Add to that, the lawn mowers, and the tractor. There's 5 totally different engine oils, on my shelf. :laughing:
 
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   / Put wrong viscosity in my Tundra truck. Forget about it? #58  
Please go back and read the first post you quoted, I said they have tightened up bearing clearances quite a bit.
As for tolerances having an affect, consider an engine that has a couple thou tolerance and one that is a couple tenth. Heavier weight higher cold flow numbers were necessary to compensate for the potential of larger bearing clearances.
Bearing clearances and tolerance are seperate things, but they do have an affect each other.

I've quoted you exactly....you didn't say tightened up clearances, you said they have tightened up tolerances.

It's pretty easy to sort out....just read your own post. Also, if you're going to respond to someone specifically, you might want to quote them so everybody knows who you're addressing.
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #59  
For anybody interested in the actual topic, this has come up time and again on Toyota forums all over the net. In short, even TOYOTA has said a 30wt oil won't hurt the engine, and they recommend 20wt for fuel economy. This discussion started back in 2007 and the engine is essentially unchanged since then.


5w20 Vs 5w30, Response from Toyota My Suprise You.. - Toyota Tundra Forums : Tundra Solutions Forum


Then, I received the response from Toyota as follows:

Thank you for contacting Toyota Motor Sales, U.S.A., Inc.

We appreciate your interest in properly maintaining your 2007 Tundra and using the appropriate engine oil for your vehicle. We apologize for your concern regarding the oil viscosity used by your dealership.
According to our records, you contacted us telephone today on June 14, 2007 regarding your 2007 Tundra. At that time we referred we advised to you that 5w-30 oil viscosity will not affect engine. Adv on next oil change can choose to use 5w-20 for best gas mileage.
Out vehicles come from the factory with natural petroleum-based engine oil. We are currently recommending American Petroleum Institute (API) grade SJ petroleum-based engine oil. In moderate climates, this oil should have a Society of Automotive Engineers (SAE) viscosity rating of 5W-30. However, 10W-30 is recommended for use in areas with higher temperatures. In our high mileage tests with preventative maintenance performed at the recommended intervals, the recommended natural petroleum-based oil has provided excellent service.
If we can be of further assistance, please feel free to contact us. Your email is documented at our National Headquarters under file #200706140107. Toyota Customer Experience
 
   / Put wrong viscosity in my Tundra truck. Forget about it? #60  
I've quoted you exactly....you didn't say tightened up clearances, you said they have tightened up tolerances.

It's pretty easy to sort out....just read your own post. Also, if you're going to respond to someone specifically, you might want to quote them so everybody knows who you're addressing.
Thanks for the advice, but re-read the second paragraph of my first post.

Moving on, this horse has been throughly flogged........
 

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