I've often wondered how Acura determines the oil life percentage as found in our RLs. Does a microchip actually sample over time the vehicles RPM, temperature, speed, stop/go habits, idle time, gear engagement ratios, etc. or does it merely determine oil life % by the number of miles driven?

Is the oil life percentage indicator, in your view, an accurate guage of the oil's true remaining life?

Does anyone know the actual "technicals" on this?

 

I changed the oil in my TL @ 3800 miles (with 60% remaining) and was told I was jumping the gun - the car knew better than I did.

So... I imagine it is driving habit, weather (temperature), and similar factor based.

 

I imagine that it factors in driving habits, temperature, rpms, frequency of high revs, distance, time in engine, etc. The system utilizes a pretty sophisticated algorithm and I imagine that it should be better than most people at determining what is an appropriate time frame for an oil change.

Plus, don't forget that the system also monitors other, non-engine determined factors to determine which level of maintenance is required too.

 

No, the other services are based upon the oil change interval.

Yes, I'd say that its an accurate representation of oil life. However, it will not take into account whether the engine is tuned-up or not, nor will it take into account the engine oil level.

 

B.S. B.S. B.S. That stupid system tells the same crap whether I put in dino oil or syntho oil. The MID is just a gimmick to get some more money from your "great deal" at the dealer.

 

It doesn't matter if you use dino or syn with our system as far as I've read. Here is what GM says about their system which seems to work the same as ours:



Mercedes was actually sued because they failed to mention that if you use dino oil the extended periods were far too long for the oil and wouldn't alert you that the oil needed to be changed until after premature engine wear has already occured.

Hopefully we won't see any of these sorts of problems.

 

I'm not understanding your logic behind the "stupid system" reasoning for the service interval indicator. Synthetic oil does not necessairly last longer than conventional oil under all driving conditions, contrary to popular belief, as synthetic oil still becomes contaminated with fuel, water, blow-by, etc under certain conditions. While the oil may not be "worn-out," the contamination levels indicate the need for oil to be changed. In addition, the oil filter may've been loaded to its capacity, making it unable to continue filtering.

If the dealer/Acura really wished to dig deeper into your wallet by recommending unnecessary services, they'd recommend an oil change every 3mo/3K, as well as a tune-up and all new fluids every 30K...

 

Yeah I too fail to see the Prof's logic since the system isn't saying to change oil every few months and if it was a gimmick for Acura to get more oil changes then it wouldn't go to like 8500km before the oil life indicator hits 10%. It is the farthest thing from a "gimmick" to get them more service money.

 

O.K. who's the oil guru on this forum? At any rate, I drive exactly the same 1200 miles on the interstate a week. The only real change could be the seasons.

I've always used M1 and I get a MID to change the oil every 6 weeks. They accidentally put dino in this winter and I got 10K before the MID. Is syn oil the joke or the MID??? My bet is the MID.

 

Its hard to say what could've caused the increase in the service interval over the winter. Less stop-n-go driving could've been the cause, but the cooler outside weather may've led to a slight decrease in oil temperatures, thus possibly causing the somewhat significant extension in oil life. On the other hand, if you solely used your RL for as a short tripper, you would've instead noticed a reduction in the service interval during the winter due to the longer warm-up period and possibly increased fuel dilution.

 

The lawyers got the 32 million!!

I only got an offer for one free oil change but only at the time the car was brought in in conjunction with another service. Yes, I was part of the "class action lawsuit" because my wife owns a Mercedes. It was like . . give us $300+ for some kind of inspection and we'll change your oil for free as part of the settlement. Trust me, Mercedes Benz owners DID NOT RECEIVE $32 million. I got $0.

I also believe that the oil change calculator is probably just a fancy odometer to measure oil change intervals. I change my oil every 5K miles regardless. The other maintenance reminder gizmo is just a cash flow enhancing machine for the dealers.

 

this is the most official info I could find: (is the same for the RL)

The TL has a Maintenance Minder system that automatically monitors the vehicle's unique operating condition to indicate to the driver when maintenance is required. Maintenance alerts are presented when the ignition is first turned on, not while driving (to prevent driver distraction). The system monitors engine operating conditions such as fluid temperatures and engine speed to determine the proper service intervals. The Multi-Info Display (MID) located below the fuel and engine temperature gauges in the instrument cluster indicates the remaining percentage of engine oil life, and then shows service is due with a "wrench" icon. A percentage-based countdown to the next service is displayed when the car is within 15 percent of the end of the service interval. A letter and number code is displayed to indicate the specific type of service that is required. If the service is missed, the MID indicates past-due mileage to express the urgency of the required service to the driver.

The system is designed to eliminate unnecessary maintenance procedures, environmental impact and expenses, while ensuring that important service issues are addressed. In some cases, oil change intervals can extend to a maximum of 10,000 miles, which could spare the owner considerable money and inconvenience over the life of the car. The owner-resettable system monitors all normal service parts and systems, including oil, oil filter, tire rotation, air-cleaner, automatic transmission fluid, spark plugs, timing belt, coolant, brake pads and more.

 

What do you mean change the ATF fluid more often?

 

Any recommendations as to the proper interval for those of us that do mostly city driving?

 

I'd change the oil when recommended by the Maintenance Minder System.

The ATF has the capability of enduring very long service intervals before the fluid is completely oxidized and the dynamic friction properties are lost. The intervals recommended by the Maintenance Minder system are perfectly reasonable for the fluid.

The Honda ATF-Z1, like the Chrysler ATF+4 and Kia SP-III, follow a new trend where the color and odor of the fluid are irrelevant to the fluid condition and burnt/discolored fluid does not constitute a fluid change. I've verified this by fluid analysis and it is not a reckless recommendation given by Honda.

However, proactive preventive maintenance is certainly harmless provided that it is done properly. Many enthusiasts enjoy changing the ATF on their Honda vehicles every 15,000 miles as they seem to experience better shifting after a fluid change.

 

Michael, thanks for the recommendation-I'll probably do it every 15k since it is cheap insurance and new fluid usually improves the responsiveness of the tranny as well as the reliability. I was used to doing a tranny flush every 15k with my Volvo 850, which had a notoriously weak AT. I don't think Acura recommends a flush, just a drain and refill-is that true? Also, what are your thoughts about synthetic tranny fluid (ie, Mobil 1) for the RL?

 

Just follow the MID. The algorithm accounts for short trips on one extreme and high engine temperatures on the other.

On another note GM went to 15,000 miles max oil change on the Corvette because the only fill reccomended is synthetic oil.

 

Wow...Every 15,000 miles!!! Says a lot for synthetic oil. I bought about $250.00 worth of Mobil1 0-20, before they stopped manufacturing it - so that should hold me for a minute or two...Anyone know what the shelf life of synthetic oil is?

 

I believe Michael's comment about 15k miles was for tranny fluid, NOT engine oil. If you read his post, he recommends using the MID for determining intervals for the engine oil. Does the MID actually notify the driver when the tranny fluid needs changing?

 

Two differennt things going on here. I commented that GM has the Corvette max motor oil change (ideal conditions) at 15,000 miles based on using synthetic oil.
I believe the Acura starts at 10,000 miles. Both systems subtract from an ideal top number based on less than perfect operating conditions.
I don't know about other maintenance reminders.

 

Mobil reintroduced the 0w20 recently.

Different engines have different drain intervals due to variations in sump capacity, operating temperatures, and many other factors. A Corvette may have a longer oil change interval than an RL due to its larger sump capacity and different engine design.

To answer the question regarding transmission fluid: Genuine Honda ATF-Z1 is a good fluid at a reasonable cost. It is the only approved fluid for this transmission. Also, unlike older transmission fluids, this fluid follows the trend of newer fluids (i.e. Chrysler ATF+4, Kia SP-III) where the odor or color of the fluid is not representative of the fluid's condition.

If you notice your transmission fluid turning brown and is emitting a distinctive "burnt" odor, there is no need for concern.

If you're interested in a synthetic automatic transmission fluid, my advice would be to use Amsoil Universal ATF. It costs approximately $7.50/qt shipped, which is only $1.50/qt more than the Genuine Honda ATF-Z1. However, consider yourself forwarned that Amsoil Universal ATF is not Honda approved.

 

Something else to consider while comparing engines and oil life... V8 engines operate at lower rpms than V6 engines, which operate at lower rpms than I4 engines, so, per mile traveled, a V8 turns less rpm than a V6, which in-turn, turns less than an I4 engine. So, that may play into the calculation of oil change interval as well, meaning that 15K may be fine for a V8, where 10K may be fine for a V6, yet 5K may be right for an I4.

 

Paul, I really have to disagree. Just as one example, my RL turns only about 1,800rpm at 70mph, whereas the V-8 in my former Infiniti M45 was cranking 3,000rpm at the same speed.

It's more a function of the gear ratios than the number of cylinders.

.
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Wow, I was basing this on personal experience. I have a friend with a Corvette and his runs at about the same rpm as your RL at 70. Our 4 Banger Camry ran at about 2500 rpm at 70 mph. My truck has a V6, and it runs about 2300 rpm at 70, but it's a 4X4 and I figured it would be geared lower because it's a truck. I have not noticed what our new TL runs at 70 because my wife drives it, and it's not easy getting the keys away from her!

 

Your friend must have an old Corvette. Here is a 2000 Corvette:




Just as a follow on you pay a huge penalty for a small engine turning big revs. If I remember correctly friction increases , at least, with the square of speed. A great case of this was the Honda 2000. A very small lightweight car that wasn't even close to a C5 Corvette in performance, size, or weight yet got slightly less gas mileage. High revs kill engine efficency.

 

Well, maybe he was doing 80! I think his is 2002 or 2003 with an automatic tranny so it's probably real close to the one in the picture. I do recall the engine seemed to be just lumbering along given the speed we were traveling! Unlike our Camry that would have been turning about 3500 rpm at 80 mph! I've heard the S2000's do run at a high rpm! I like the engins in the Indy cars here, at anything below 100 mph they sound like their popping and spitting, yet get them up to 200+ and it's just a sweet steady whine!

 

While a V8 may turn at a lower rpm, this does not dictate a longer oil change interval. Larger engines (i.e. V8) consume more fuel, and as a result, will deposit more contaminants into the engine oil. If anything, all things being equal, a V8 engine will have a shorter service interval for that reason alone...contamination.

 

V8's take longer to warm-up too so these contaminates are less-likely to burn-off

 

"...Larger engines (i.e. V8) consume more fuel, and as a result, will deposit more contaminants into the engine oil. If anything, all things being equal, a V8 engine will have a shorter service interval..."

"V8's take longer to warm-up too so these contaminates are less-likely to burn-off"

Good thing the RL doesn't have a V8 then, isn't it?

LL