2002 Subaru Outback Makes Roaring Noise When Gas Pressed

subaru
outback

#1

2002 Outback, runs great EXCEPT for very annoying roaring, revving noise when gas pedal is pressed and going over 35mph. Sounds like car is running 60 mph in second gear. It is an automatic transmission. Don’t think it’s a transmission problem, gears change smooth (does about 2300 rpms at 65 mph). Sound will stop and runs normal if you let off gas. Noise is loud. Bearings, exhaust, etc.??? HELP. THANKS


#2

I assume that you a tachometer since you mentioned 2300 rpms at 65. So what does the tach do when you get this roaring and it “Sounds like the car is running 60mph in second gear”? Do the rpms shoot up? If so, then your transmission is slipping and/or not shifting well, probably on the 2-3 shift. Slipping will seem like “smooth” shifting. In fact, smooth shifting is because of slipping, but the slip is supposed to be minimal and well controlled within design specs. Any number of problems can cause too much slip, and it doesn’t have to affect all gears or shifts.

Have you checked the transmission fluid? How many miles are on it? What is the history of transmission service on it?


#3

It has 155000 miles. Tach doesn’t shoot up at all - runs consistently about 2300 at 60 to 65 mph. “roaring” noise seems to be connected to pressing on gas pedal rather than transmission. Noise will stop if you let off gas and let car “drift” (ex: going down a hill where speed pretty much maintains) tach stays consistent at all times. Transmission fluid has been checked and is ok. How often should fluid be changed in tranny?


#4

Car has drive and low 3, 2 and 1. If you put car in low 2 and run it up to 60 mph, rpms will go up to 3500 or better and engine “roars”. If you change car from low , up to drive, rpms drop to 2300 but “roaring” doesn’t go away. That’s best description I can give of the sound.


#5

"How often should fluid be changed in tranny? "

Every 3 years, or every 30k miles, whichever comes first.
If you have not followed that type of maintenance schedule, then–unfortunately–the transmission is on target for failure by this point.

I am not trying to spread gloom & doom, but that is reality for most cars once they get past 120k w/o the transmission being serviced according to that schedule. Thus–cigroller’s question.

I would suggest a visit to an independent transmission shop that has been in business for at least 3 years. Ask them to do a fluid & filter change, and to assess the problem that you are reporting.

Whatever you do, DO NOT go to a chain-run transmission shop, such as AAMCO, Lee Myles, Cottman, or Mr. Transmission, where almost every customer is told that they need a new transmission–whether they really do or not.


#6

Have you checked the fluid level of the front differential/final drive? The final drive uses GL-5 lube which is separate from the transmission itself.

It sounds like the problem may be related to the final drive pinion shaft bearings or the differential carrier bearings. They would become loaded with throttle application.

Good luck on this.


#7

“…noise when gas pedal is pressed and going over 35mph.”

If you don’t get the noise immediately when first accelerating from a stop, that pretty much takes an exhaust leak out of the equation.


#8

I don’t know how subies work but is it different with theac on or ac off? could be a failing coolant fan.


#9

“Tach doesn’t shoot up at all - runs consistently about 2300 at 60 to 65 mph”

I didn’t mean when you’re cruising at 60-65. It sounded to me like the noise was a temporary thing in a particular speed range. If the roaring noise there any time you’re on the gas and over 35, then see Researcher’s post.


#10

Thanks to everyone for their thoughts and suggestions.
Barkydog - doesn’t matter if the ac is on or off.
cigroller - the roar is constant after car reaches about 35 mph in speed. A friend said might be wheel bearing - but I thought if it was a wheel bearing, it would keep making the noise even if I let off the gas because the wheels were still turning?? Stops if I take foot off gas.
Going to garage Friday for tires and mechanic is going to check
it again for me. Am going to take a copy of the suggestions Researcher listed and have him check those things.
THANKS AGAIN!!


#11

lillith, yes. Wheel bearing noise will remain the same with your foot on or off the gas.