changing automatic tranny fluid - how often

[Andy Leszczynski]

Hi,
How often it should be changed to provide optimal performance yet
guarantying the long lasting life.
If it is changed to often or not at all, could it shorten the life of
tranny and damage it?

Thx,
A.

 

[Rick Courtright]

How often it should be changed to provide optimal performance yet
guarantying the long lasting life.

Hi,

I've owned exactly one automatic in my life, and it's not my Subie! It's
a Toyota Camry. Toyota recommends changing at 30k miles on my car. The
previous owner was an absolute stickler for maintenance (wish she'd
owned my Subie before me, too!) and had the trans fluid drained and
flushed (where they run 12-15 qts of fluid thru to really clean things
out) every 15k miles. The car had 214k miles when I got it, and 228k
now. No trans problems so far... (he says, knocking on wood!)

I've taken a different tack on this, based on what a lot of Toyota
"fans" have told me: instead of waiting until 15k or 30k, I change the
fluid every second oil change (around 7500 miles.) This particular car
only releases 2 1/2 qts when you drain the trans (I haven't a clue
what's still in the torque converter--my book says nothing on the
subject), and it's easier than changing the motor oil and filter
(there's just a drain plug, no replaceable filter that has to come out
when you drain the ATF.) Judging by the stick, the fluid actually seems
to stay cleaner than going the 15k miles. I don't know what happens when
you drain a Subie trans, but this is a regimen you might ask about.

Friends of mine owned a trans shop for years, and they told me you
should follow one of two regimens WRT changing fluid: change early and
often, or not at all. The reason behind the latter recommendation was
that if you don't change for a long time, then all of a sudden decide
it's time to start doing some "preventive" maintenance, you may be
opening up a can of worms with old crud breaking loose in the trans with
new fluid. Naturally, the trans will last far longer with the "early and
often" regimen.

So judging by what they told me, I'd guess you won't hurt anything by
changing often, but will probably shorten the life of the trans
considerably by not changing often enough.

Rick

 

[John Rethorst]

How often it should be changed to provide optimal performance yet
guarantying the long lasting life.

For my '01 OBW, the recommended interval is 15,000 miles.

If it is changed to often or not at all, could it shorten the life of
tranny and damage it?

I would think that not changing it would shorten the tranny's life considerably.

 

[y_p_w]

Andy Leszczynski wrote:




Hi,

I've owned exactly one automatic in my life, and it's not my Subie! It's
a Toyota Camry. Toyota recommends changing at 30k miles on my car. The
previous owner was an absolute stickler for maintenance (wish she'd
owned my Subie before me, too!) and had the trans fluid drained and
flushed (where they run 12-15 qts of fluid thru to really clean things
out) every 15k miles. The car had 214k miles when I got it, and 228k
now. No trans problems so far... (he says, knocking on wood!)

I've taken a different tack on this, based on what a lot of Toyota
"fans" have told me: instead of waiting until 15k or 30k, I change the
fluid every second oil change (around 7500 miles.) This particular car
only releases 2 1/2 qts when you drain the trans (I haven't a clue
what's still in the torque converter--my book says nothing on the
subject), and it's easier than changing the motor oil and filter
(there's just a drain plug, no replaceable filter that has to come out
when you drain the ATF.) Judging by the stick, the fluid actually seems
to stay cleaner than going the 15k miles. I don't know what happens when
you drain a Subie trans, but this is a regimen you might ask about.

My 2004 Subaru warranty guide only recommends "inspection" at 30K
mile intervals. They do recommend changing the ATF every 15K miles
under towing conditions. There is no additional recommendation for
short trip, cold weather, or dusty conditions (I suppose it's a
relatively closed system).

My take is that it would be worthwhile to change the fluid at the
"inspection" intervals. I've got a manual WRX. Although I had
performed my second change in less than 15K miles, I've settled on
every 30K miles (the "inspection" interval). I tried different
fluids to find out what felt better.

 

[Edward Hayes]

I'm a DIY person and change mine at 30.000 miles. My car is used daily
in 85 degree temps with some traffic. Since a pan drain gets about 40%
out (4 quarts of 10 or so) I chose to drain at 30K. The book say
somewhere between 15 and ?100,000 so I picked a safe ground since I
keep my cars to 120-150,000 miles and transmission repair or
replacement is expensive.

 

[Al]

Hi,
How often it should be changed to provide optimal performance yet
guarantying the long lasting life.
If it is changed to often or not at all, could it shorten the life of
tranny and damage it?

Thx,
A.

The fluid in my '91 Jeep is the original. No problems what so ever.

Al

 

[bg]

The fluid in my '91 Jeep is the original. No problems what so ever.

Al

Try changing it and then see if your statement holds true.

 

[Edward Hayes]

I'll wait to see if your Jeep makes it to the 150,000 miles I'm
looking for.

 

[John Rethorst]

For my '01 OBW, the recommended interval is 15,000 miles.

I misread my manual. No such recommendation. The schedule calls for inspection
every 30,000 miles.

Now I'm wondering why my dealer recommended replacing the ATF and fuel filter at
45,000.

 

[y_p_w]

I misread my manual. No such recommendation. The schedule calls for
inspection every 30,000 miles.

Now I'm wondering why my dealer recommended replacing the ATF and
fuel filter at 45,000.

I think it's a good idea to change the filter some time, regardless of
what the manufacturer recommends. My warranty booklet says that the
non-turbo fuel filters should be replaced every 30K miles.

 

[ed]

My 2004 Subaru warranty guide only recommends "inspection" at 30K
mile intervals. They do recommend changing the ATF every 15K miles
under towing conditions. There is no additional recommendation for
short trip, cold weather, or dusty conditions (I suppose it's a
relatively closed system).

My take is that it would be worthwhile to change the fluid at the
"inspection" intervals. I've got a manual WRX. Although I had
performed my second change in less than 15K miles, I've settled on
every 30K miles (the "inspection" interval). I tried different
fluids to find out what felt better.

From what I've read, heat is the #1 tranny destroyer, so if you want to
avoid problems, have a transmission cooler installed, especially if you tow
or carry heavy loads in hot weather. I've had one on a Nissan and an Eagle,
both did about 250k km (150k miles) without problems.

A salesperson I know did 750k km (450k miles) on an Eagle (Mitsubishi), with
1 tranny oil change at 350k km (210k miles), but almost all highway miles,
which is much easier on the trans oil than city driving. The car was still
working at that point, but was written off due to an accident.

Since there is no combustion or dilution from fuel, tranny oil lasts much
longer than engine oil. Changing it at 30k miles is more than adequate for
most vehicles, seeing as most people never change it at all. Most garages
change the oil by connecting to the oil cooler lines, and some websites have
a how to if you want to do it yourself. Changing at 15k miles is way too
often. The filter should be changed as well (requires pan removal on most
vehicles, but some Subarus have an external filter).

 

[John Rethorst]

Now I'm wondering why my dealer recommended replacing the ATF and
fuel filter at 45,000.

I think it's a good idea to change the filter some time, regardless of
what the manufacturer recommends. My warranty booklet says that the
non-turbo fuel filters should be replaced every 30K miles.[/QUOTE]

What year/model do you have?

 

[y_p_w]

From what I've read, heat is the #1 tranny destroyer, so if you
want to avoid problems, have a transmission cooler installed,
especially if you tow or carry heavy loads in hot weather. I've
had one on a Nissan and an Eagle, both did about 250k km (150k
miles) without problems.

The biggest problem may be possible warranty issues. In practice
it's a good idea. High ambient temps problem don't heat up the
auto tranny as much as heavy loading.

A salesperson I know did 750k km (450k miles) on an Eagle
(Mitsubishi), with 1 tranny oil change at 350k km (210k miles),
but almost all highway miles, which is much easier on the trans
oil than city driving. The car was still working at that point,
but was written off due to an accident.

I guess Subaru feels that city driving isn't **that** big a deal.

Since there is no combustion or dilution from fuel, tranny oil
lasts much longer than engine oil. Changing it at 30k miles is
more than adequate for most vehicles, seeing as most people never
change it at all. Most garages change the oil by connecting to
the oil cooler lines, and some websites have a how to if you want
to do it yourself. Changing at 15k miles is way too often. The
filter should be changed as well (requires pan removal on most
vehicles, but some Subarus have an external filter).

Recent Subarus use a spin-on transmission filter. To avoid mixing
them up, the OEM filters are marked ENGINE and TRANMISSION on the
ends.

 

[Al]

I'll wait to see if your Jeep makes it to the 150,000 miles I'm
looking for.

It's at 100K now. Not much for 14 years. All it needs is a paint job.

And I'm not dissing Subies, I'm on my second one.

I have a friend who only buys used Lincolns. He keeps them for 4 or 5
years and never changes any fluids, only adds. It's worked for him for
the over 25 years I've known him.

Al

 

[y_p_w]

I think it's a good idea to change the filter some time, regardless of
what the manufacturer recommends. My warranty booklet says that the
non-turbo fuel filters should be replaced every 30K miles.

What year/model do you have?[/QUOTE]

2004. The booklet is at home, and I'll take another look to double
check. I believe the turbo models spec every 60K miles. Perhaps it's
a larger filter?

 

[Rick Courtright]

I have a friend who only buys used Lincolns. He keeps them for 4 or 5
years and never changes any fluids, only adds. It's worked for him for
the over 25 years I've known him.

Makes ya wonder, doesn't it? We've all known people who've done this and
gotten away with it (though I wouldn't buy a used car from any of them!)
Many of us have probably also known people who never brushed their teeth
and still don't qualify for a Jeff Foxworthy "smile of the week"
picture, but should we recommend not brushing one's teeth based on a
single anecdotal person?

A client has an '80 Lincoln, purchased new, meticulously maintained (his
wife loves the car, won't let him trade it in, but will NOT abide car
trouble--tall order to fill, eh?) and driven all over the country many
times. I don't know how many miles it's gone past the 200k he had some
time back. Setting aside the styling issues, I wonder who's spent more
dollars per mile over that quarter century, my client or your friend?
And, I'd go anywhere in my client's car without worry. Would it be
likely I'd feel the same about your friend's? "Worked for him" could be
quite a relative concept!

Rick

 

[y_p_w]

2004. The booklet is at home, and I'll take another look to double
check. I believe the turbo models spec every 60K miles. Perhaps it's
a larger filter?

OK - took a longer look.

(R) means replace as "Recommended service for safe vehicle operation."
There is also an (I) as a recommended inspection. An R w/o the
parentheses means replace period.

For the fuel filter, it has (R) at 30/60/90K miles, and R 120K miles.
The WRX-STi has the (R) at 60K miles and R at 120K miles.

 

[Al]

Makes ya wonder, doesn't it? We've all known people who've done this and
gotten away with it (though I wouldn't buy a used car from any of them!)
Many of us have probably also known people who never brushed their teeth
and still don't qualify for a Jeff Foxworthy "smile of the week"
picture, but should we recommend not brushing one's teeth based on a
single anecdotal person?

A client has an '80 Lincoln, purchased new, meticulously maintained (his
wife loves the car, won't let him trade it in, but will NOT abide car
trouble--tall order to fill, eh?) and driven all over the country many
times. I don't know how many miles it's gone past the 200k he had some
time back. Setting aside the styling issues, I wonder who's spent more
dollars per mile over that quarter century, my client or your friend?
And, I'd go anywhere in my client's car without worry. Would it be
likely I'd feel the same about your friend's? "Worked for him" could be
quite a relative concept!

Rick

Massachessetts to Florida several times a year and never got stranded.
Once he lost the main crank pulley on the way home from work; had
nothing to do with fluids.

My '71 Jag, which I bought new, still has the original brake fluid. The
calipers have not frozen up yet; knock on wood. 86K miles on it. I would
have sold it 4 years ago, but my son wants it as his legacy. Jeez!

Al

 

[Rick Courtright]

Massachessetts to Florida several times a year and never got stranded. ....
My '71 Jag, which I bought new, still has the original brake fluid. The
calipers have not frozen up yet; knock on wood. 86K miles on it. I would

I'd guess you've both been living on the lucky end of the spectrum.
Congratulations!

Hope your son enjoys the Jag, but plans on tearing down the whole
braking system before driving it much... while the brakes haven't
failed--yet?--34 yrs w/o internal maintenance has certainly not
~improved~ the system.

Rick

 

[Al]

I'd guess you've both been living on the lucky end of the spectrum.
Congratulations!

Hope your son enjoys the Jag, but plans on tearing down the whole
braking system before driving it much... while the brakes haven't
failed--yet?--34 yrs w/o internal maintenance has certainly not
~improved~ the system.

Rick

OK, I know this is a Subie newsgroup, so one last word.

I'd give it to him now, except his condo doesn't have a garage. Once he
gets a garage, it's his. He's been buying parts on eBay and the like so
that he'll have a bushel basket full when he starts his rebuild.

BTW, even the paint is orginal and badly faded but not peeling.

Al