Engine Oil Overfill Question

I just bought a '14 Access Cab, Base, 2.7L, 31K miles, about a week ago from a Toyota dealer. Not having good luck reading the dipstick, I searched on here and found the suggestion (that works great) to remove the dipstick, let the truck sit about 15 minutes, THEN insert the dipstick and check the level. Well...I now find that I am about .75 to 1.0 inches above the "upper" mark. So I drained about 1 quart...now it measures exactly on the "upper" mark.

That oil was changed (and a quart too much added) 672 miles ago during the "Toyota Certified Inspection". Almost all those miles are highway miles...by me. Do you guys think it's possible that any damage was done as result of the too much oil? Everything sounds and feels fine.

 

I was wondering the same thing if the transmission oil was over filled? Two good questions here...

 

ok...so I did a Google search to find related threads on TW...couldn't find anything using the search on here. Apparently this topic has been beat to death. Bottom line...I will be using the dipstick.

 

If an engine is seriously overfilled, it can cause damage. An extra qt, assuming the dipstick is accurate, won't hurt anything.

 

That seems to be the big question. Personally, given the choice between believing the Manual or the dipstick...I will choose the dipstick.

 

I finally found a good way to read it. Remove the dipstick and wipe clean...wait 10 minutes to allow oil on sides of dipstick spout to drain down...Insert dipstick fully...Remove dipstick and read. I found that one side has a very small amount of oil "residue", but the other had none...works great.

I'm really "not concerned" with the quantity of oil that goes in...I'm gonna add it unitl the dipstick reads at the upper mark.

 

An army of engineers with billions of $$$ on the line say 6 qts, the $.50 piece of stamped metal made by the lowest wage worker says otherwise...

But really a dipstick just shows a range of 'normal' like most gauges. A little above, a little below, it's fine.

And even if the stick is 100% accurate, you need to find the exact angle the engine needs to be sitting at in order to make the most accurate tool, accurate. Mild incline/decline, tools is off. A little air out of the tires, tool is off. You're fat and standing on the bumper, tool is off.

Theres just not any reason to chase 'perfect' when odds are you can't obtain it, and even if you do, it doesn't matter. It either has enough oil, or it doesn't. (ignoring dumping a LOT extra in and causing damage).

When I was in HS body shop we had 1 genius with an old wagoneer. I don't know how much oil was supposed to go in it but he bought a case and 'figured I'd just add it all since I had it'. That went badly

 

Good, because the manual tells you to trust the dipstick.
http://www.toyota.com/t3Portal/document/om/OM35A38U/xhtml/OM35A38U_0026.html?locale=en (see note in page 534)

Because of engine production tolerances, the level of the oil in the sump is more important than the volume of oil. Too high and the crankshaft can whip up the oil and introduce a lot of air into it. That's it.

It takes only a single engineer to design a high-performance engine. The army of engineers is there to find ways to make it as cheaply as possible. There's enough automation and assembly jigs in place to ensure the dipstick can be made accurately by the lowest wage worker.

 

I'm definitely not chasing perfect...I just want the level between the marks where it should be...and if I follow the manual...it is most definitely is NOT between those marks.

I doubt the Tacoma is the first car in history where the dipstick is not the final word for the oil measurement.

This horse has been beat to death already...it's settled for me. I do appreciate all the input!

 

Oddly enough...I am actually an Automation Engineer in an automotive plant...and you are exactly right. Massive amounts of time and money are spent on controls to eliminate the possibility of worker error. Basically they push a button, the tool does the work...if an error occurs, the line stops, a "supervisor" arrives, corrects the error, then starts the line back up.