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Doug, ASE Certified Technician
Category: Mitsubishi
Satisfied Customers: 8606
Experience:  Mitsubishi employed and Factory trained ASE certified technician
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Mitsubishi Lancer ES: We have an 09 Lancer and either after

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We have an 09 Lancer and either after a time or above 65mph the car begins to whine evenly and with acceleration gets louder. Doesn't continue a lower speeds. Have had fluid and filter changed twice as recommended, but not at dealer. Car has 83000 miles. Should we worry? Thanks

Once the whine occurs, does it continue below 65 mph when you decelerate, or does it stop abruptly at 65 just like it starts?

When you are at these higher speeds and you go through a turn, does the noise change pitch at all?
Customer: replied 4 years ago.

Once it starts it continues until you stop for awhile. Noise pitch doesn't change, just how loud it is. Thanks.

Thank you.

Could you describe the whine a bit? Is it a relatively higher pitch sound or more low tone? Is there something it sounds like you could compare it to?

I am also assuming from your comments regarding the transmission fluid that the noise is definitely from the front of the vehicle.
Customer: replied 4 years ago.

Sounds like a supercharger, a high pitched whine that you can hear when cruising and gets louder when you accelerate. In front middle, sounds like it is close to the dash. Doesn't seem to be from motor or tranny necessarily.


Is it possible you are hearing electrical feedback? Like on older vehicles you used to get "alternator whine" that could be heard through the electronics?
Customer: replied 4 years ago.

I was thinking alternator or a/c fan or compressor but compressor turned off doesn't stop the noise. More familiar with older cars for sure.

Thanks, XXXXX XXXXX a possibility then.

This sounds a bit funny, but have you ever noticed if the noise changes when you let off the gas pedal? Specifically like if you are moving at a certain speed and the noise is constant and consistent, then you let off the gas does the noise momentarily stop or get noticeably quieter?
Customer: replied 4 years ago.

The whine lowers in pitch on deceleration

Thanks, XXXXX XXXXX when the foot is off the gas pedal the pitch changes, then returns when you reapply it... regardless of significant change in road speed?
Customer: replied 4 years ago.

Once you have been driving for awhile and/or above 65mph

Thanks. I just wanted to make sure we weren't hearing the throttle body (an issue on these cars sometimes).

How do the front tires look? Any unusual wear on the crowns of the tires?
Customer: replied 4 years ago.
Tires wearing well but "sing" pretty well. Throttle body?

The throttle bodies on these cars (The part that the gas pedal controls to increase/decrease engine speed) are known to make a whining noise, more so as they get older. It would be very definitive though when you let go and reapplied the gas pedal and that doesn't sound like what you are describing.

Regarding the tires, if you can differentiate between their noise and the whine you are hearing, we can rule them out.

I really have a hard time placing it on the transmission due to the pitch not changing only the volume... most transmission issues will increase in pitch with speed.

You mentioned changing the fluid for the transmission, what type of fluid did you use?
Customer: replied 4 years ago.
First time blue fluid, second time not blue. Assume color doesn't matter. Whine lowers in pitch when speed slows

Fluid is extremely important in this transmission, as the incorrect fluid will score the cones in the transmission and result in a whine.... if the whine is changing pitch then this may be more relevant.
Is there a notable chain of events regarding the noise and the fluid changes? For example it happened within 1000 miles of a fluid change etc?
Customer: replied 4 years ago.
will check right now
Customer: replied 4 years ago.
6 quarts at $8 per quart, Will call Monday to see what they used, So if tranny issue, would it only show at high speeds or any time or just acceleration?
It depends on the nature of the failure with regard to transmission issues.
Specifically if we had the wrong fluid in there what will happen is the lubrication between the two CVT cones and the CVT belt will be insufficient and it will cut very fine grooves into the cones. When this occurs you will get a whine at upper speed (ultimately it depends on where the groove is located to determine what speed(s) it happens). This is due to the way the inside of the transmission works.
Inside you have two collapsing cones, similar to a go kart clutch. These cones increase and decrease in size to vary the ratios between them, as one drives the other with a large steel belt. When you get a score on one you will get the whine once you reach a ratio that hits the scored area to the belt. Then unless you drastically change speed/acceleration the noise will remain as the other cone moves to fine tune the speed.

Typically when we see people put incorrect fluid in, this will occur not long after... sometimes as early as a few hundred miles, but in a few cases I have seen a few thousand miles before severe damage was done.

Technically the only guaranteed fluid to work is the proper Mitsubishi CVT fluid (or other Jatco CVT fluid). The fluid will be green only and will turn a yellow/light brown color within a few hundred miles. The blue fluid is potentially correct (the green color is in a hue that could be argued blue by some people).... but any other color will be a definite problem. These are industry standardized to prevent accidents, as CVTs are extremely sensitive due to the direct steel on steel contact. It can take as little as 4 ounces of "red" or universal transmission fluid to cause damage to the transmission.

Find out exactly what was used, if it was "transmission fluid" or otherwise not specifically engineered for either Mitsubishi or Jatco CVT transmissions, odds are this will be the cause of your noise. And to that end, there will be some liability on the shops part for putting damaging fluid in the transmission. Once the CVT cones are scored, there is no repair. You can live with it or replace it, but the cones are not serviceable on this manufacturers CVT transmission at this point (and there are no plans for them to be in the future at this time either).
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