Thanks. I can see that smaller clearances would potentially call for a lower viscosity in order to improve flowrate to and around the surfaces needing lubrication. My observation is that while I read that tolerances have been reduced, I have never seen a post that says tolerances were this number specifically and now they are this - specifically. Surely these tolerances can be measured and surely they have been. Somebody knows - but I have never seen the numbers. I conclude that the reduction of tolerance thing is a wive's tale. Tolerances have been tight for a very long time. I have been around awhile, and don't recall any of the pistons in the 289 in my 67 Cougar trying to figure out which hole to enter. Machinery of the first order has been built for decades. The Germans in particular are reknown for their crafstmanship in everything from textile machinery to a Messerschmidts.

So, what are we to make of the oil thing. EPA dudes. They rule. No - really - they rule. You can't build a turn lane to reduce congestion without the EPA's approval - anywhere in the US. Is it to far a stretch to concede that the EPA has "encouraged" auto manufacturers to recommend a lower viscosity to supposedly "gain" 1/10th of a mile per gallon at the expense of durability. I think not. This theory is supported by the EPA's massive disdain for older cars. Crush Not Restore is their mantra.

With all that said, I think a switch to either 0W-30 or even 5W-30 of a top of the line synthetic is in order. I'll report back about every 10,000 miles to discuss the impact.

 

Toyota revised the recommended oil viscosity for some engine models to 5W-20 and 0W-20.

http://www.chrysanindustries.com/pdf..._tsb071002.pdf

The last paragraph in the TSB states to only use these viscosity lubricants in the engines listed.

Why this caution statement? Why not recommend these oils for all Toyota engines unless there was something different in the engine design.

 

Fair point. I am not surprised that there is an explanation of some sort out there, and am not surprised at its brevity. Note the very first thing emphasized in the TSB - fuel economy. It is my experience that notes such as this contain first the real reason for its issuance and then contain the add-on stuff to further add justification for its release. People always rationalize their decisions with reasons made up after the fact (yes officer, I was speeding - but my mom is sick and needs these other three beers left in the sixpack to relieve her terrible headache).

You note that their must be something different in the engine design that mandates use of 0W-20 or 5W-20. Ok. What is it? You may not know. No problem. I don't know either. Somebody knows. We find ourselves back to the "tighter tolerances" thing. Its easy to say, but there are enough wrenches out there that somebody would have posted something that says "hey, watch out pulling a plug out of that new V-6 - the holes are a lot tighter" or something like that. It ain't happened. Are engines differnet than they used to be? Electronically - absolutely. Mechanically - there is nothing new under the hood that hasn't been sold before (see the 1977 Cosworth Vega, or a 1956 fuel injected Cadillac - from the factory).

I should say it ain't happened on the Toyota. It has happened on the Ford Triton 5.4. The plugs are skinny - I mean real skinny. You need a socket with a built in extension. And - they break - a lot. You have to pull a head when this happpens. Not good.

Anyway, I still look at that upper number and think that it ain't much thicker than Coca-Cola at its thickest.

Remember - it isn't true that the EPA does not care about durability. Far from it. They hate it. They want stuff to wear out. And they don't want a rebuild to be easy or cheap. They want it to be an economic slam-dunk that you should abandon the old, suck it up, and buy the new vehicle that will of course meet the ever tightening emissions standards.

 

I understand your position.

Toyota (as do most corporations) rarely provide detailed info into why they make decisions and even more scarce is hard data backing up a decision. This can backfire for companies when the public and congress no longer trusts them to build decent quality, safe products.

Toyota as other car manufactures does not appear to be interested in aftermarket or home shop repairs on their cars. They gear everything to having repairs done at the dealer. This is one reason dealers have large quantities of specialized tools, service data, etc, (given or sold to them by the car manufacturer).

Car manufacturers often make repairs difficult. The older Honda's required pulling the axle hub off to change the disk brake rotor. Why stick with this old design when Toyota and other manufacturers of the same year allowed replacing the rotor without needed to take the front end apart? Maybe it cost to much for Honda to change the design, maybe the Honda dealer had the tools to do the job much faster then a third party shop or home mechanic?

After having years of success with the 5S-FE and 1MZ-FE why are the newer engines having problems. Did Toyota forget how to design engines? Look at all the bad PR, some in my opinion misplaced, did Toyota forget how to build cars?

Some of these issues are major and have cost the company billions yet Toyota (and other companies) rarely provide hard details as to what happened, just more PR and promises to do better.

At one time Toyota was even threatening to sue websites posting links to copyrighted Toyota repair info. Interestingly these same sites often were full of members who supported Toyota.

I don't know why Toyota is recommending to use these viscosity oils. Fuel economy of course is one reason. The company is now on some kind of go "green theme" and increased fuel economy along with an increase in oil change intervals is in line with this theme.

0W-20 is a full synthetic oil. Research supports synthetics are superior to mineral oils in many areas. Perhaps this factors into Toyota's decision.

Of course as stated before Toyota never explains why.

The TSB did state using these oils in older cars may cause smoke issues. If nothing has changed in engine design then again, why not recommend these oils for all engines. Or better yet, Toyota branded super premium oil! Alas, they hedged on doing this.

Why, I don't know. Perhaps they did not test these oils on the older engines and did not want to risk another class action law suit by owners claiming Toyota had recommended oils that were now causing premature engine failure.

I have no hard data to support why Toyota is now recommending these oils. Yet, I have no hard data that other viscosity oils work equally well or not. In this case it is in my opinion safer to go with what Toyota recommends.

I would however stick with a synthetic oil and reduce the oil change interval period (assuming oil analysis is not done).

In my opinion, this would be the safer way to go.

When sufficient numbers of Toyota owners start posting using this or that oil (not on the recommended list) works fine over a normal engine life time for these specified Toyota engines models, or Toyota posts detailed findings as to how it picked these oils, then I might change my opinions.

 

I also have a 4cy 2007 camry with 52,000 miles that suddenly started burning a quart of oil every 1,000 miles.
I have a cement driveway that shows no oil leaks, and I have not noticed smoke coming out of the tailpipe.
the dealer marked (on the advice of toyota tech) all the places oil can be taken out and had me drive another 1,000 miles. it again used another quart...so now toyota had me bring the car in, and kept it for five days and gave me a new loaner car.
the gave my camry a new short block (with new pistons, rings, crank, etc) and also resurfaced the head before they attached it to the new block and added new gaskets etc.
all in all close to $5,000 in work, and did not charge me a dime.
made me a toyota owner for life.

 

I am not so lucky, my 2007 camry has 80000 miles and just noticed burning oil a few oil changes ago. My machanic researched this and recognized that it is an increasing problem that toyota is denying to help out with, at least for those out of warrenty, Customer service will not listen. I was quoted a cost of $4000 for the repair. so much for toyota reliability.

 

You might make copies of every post you find about this problem, then approach Toyota again. Be polite, your out of warranty.

If this does not work, try going up a notch to Toyota Corporate customer support.

I doubt Toyota will do anything but never know.

As a last recourse you might write whomever is the current president or CEO of Toyota, along with sending copies of all the posts. Be polite as venting will just turn them off.

Again I doubt if anything will happen, I do suspect whomever is charge is not aware of this problem only knowing what the yes people are telling him. It takes a lot of complaining to get a corporation to act, Toyota is no different. But Toyota has acted in the past on issues formally dismissed by the dealer when enough people complained.

I personally would take the car to a non-Toyota dealer for repairs. If they screwed my once I am not going to let them make a profit off their own poor engine design.

 

I have a 2007 Toyota Camry LE that is burning a lot of oil. It is not unusual for it to burn 2-4 quarts between oil changes. I have complained about this and am now having my second oil consumption test. I am told that they don't know what the problem is at my dealership. I am very concerned as my car has high mileage and is no longer under warranty .

 

You might review posts at the Toyotanation website, a much larger membership.

I thought the problem was the piston rings, but can't remember. Hence suggest reviewing posts or asking at the TN site.

What engine, V6 or 4 cylinder. how many miles on the car, what was maintenance like, what is your oil change interval, did the problem just start or happen over time?

A high mileage engine with just OK maintenance may burn (or leak) say 1 quart every 3K miles, so 2 quarts every 6K miles,4 quarts would be high.

The dealer should be up to speed on all ongoing issues with Camry as they receive service bulletins, etc. If your engine could be one that is effected by Toyota design defect don't know, need more info.

 

I have the same issue with my 2007 Camry Le. It was 2,500 miles and 2 months since my last oil change at the dealer. Just a few days ago the oil light was coming on an off. Checked the oil and the dip stick was bone dry. Brought it to the dealer and they said there was almost no oil in the engine. They did the change and told me to come back in a 1000 miles. The car has 28,500 miles on it.