1 2
procainestart
procainestart Dork
11/3/10 3:12 p.m.

A friend's wife took their '03 Outback with 100k to the dealer for an oil change. The dealer said the autotrans fluid is "burnt." I don't know jack about automatics so did a little googling and see that this can happen when you overtax the transmission, but does this mean it's on its last legs? At only 100k miles? This car is just a kid/grocery hauler: no towing, no extreme driving conditions. Another friend has basically the same car and her transmission went with less than 130k.

Thanks...

curtis73
curtis73 PowerDork
11/3/10 5:27 p.m.

As the manager of three Cottman transmission locations, I can safely say it does not necessarily mean you need a rebuild. Unless you're in central TX... then I recommend a Platinum rebuild with new axles and wheel bearings

Burnt fluid means burnt fluid. Auto trannys get hot. They use friction clutches that are held together by hydraulic pressure and are bathed in ATF as well. Once you're in gear and going, theoretically there is no slipping or wear between those clutches, but just like with a manual tranny, during shifts is when those clutches are being applied and released. That's when they slip. They make pretty crazy localized heat. After years of wearing off friction material, the fluid becomes abrasive and accelerates wear... which is why fluid changes are recommended.

At this point if the transmission is working properly, pull the pan, change the filter, and go about your business. Some people say you shouldn't do a tranny flush, but I don't stress too much about it. Pulling the pan will replace about 4-5 quarts of the total 9 or 10 that is in there. Doing a flush will replace it all which can be a bit of a shock to the clutches (but that is another lecture).

I do flushes on cars with less than 100k (depending on the transmission and use) but stick with pan only on older or HD vehicles.

I won't sugar coat this... the 5EAT and 4EAT transmissions in the Subarus are not the greatest. The fact that you are experiencing burnt fluid at 100k is perfectly normal but it should be addressed.

You might be surprised at how some of these modern automatics suck. Jags are lucky to make 60k. Rovers you're lucky to make 40k. 98-05 Hondas are often good for 100-150k. 02-07 Maximas? Fuhgettaboutit. No parts available. 9 times out of 10 you have to buy a new tranny from Nissan for $3000 and they fail about every 60k.

Don't even get me started on VW.

procainestart
procainestart Dork
11/3/10 6:13 p.m.

Thanks for the info, Curtis. Sweet fro, btw.

Curmudgeon
Curmudgeon MegaDork
11/3/10 6:52 p.m.

One thing I learned over the years: lots of the manufacturers claim a 'lifetime fill' or '100k interval' transmission fluid. That is bullE36 M3. 60k max on ANY car, I don't care who made it or what kind of fancy fluid it uses. That's assuming no towing use. Towing, down to 30K max.

Or, do like all the consumer advocate websites etc say, save yourself some money and run the stuff till the tranny blows up. Curtis and I will be very happy to see you.

Oh, and also be sure to run the engine oil to the max interval for every change.

Brian
Brian UltraDork
11/3/10 7:48 p.m.

drain and refill with a good synthetic and drive happy. I have done it on several trans, including a subaru

wbjones
wbjones Dork
11/3/10 7:51 p.m.

along the same lines... question for curtis73:

my '95 Impreza with 230k occasionally (especially after going up some very steep hills ... of which we have plenty here) gives off a faint burnt smell... fluid has been drained (no pan removal) and refilled every 30k since new... it's just now starting to shift pretty hard (sometimes) from first to second... what's the next step ? wait for failure..?? or is there some PM I can do to put off a rebuild ?

sorry for the thread jack... we can now return to our regularly scheduled programing...

friedgreencorrado
friedgreencorrado SuperDork
11/3/10 8:49 p.m.

In reply to curtis73:

Curtis, I think you've taught me more about automatics in that one post than I've been able to pick up on my own in 20yrs. Of course, since the only one I had was in the truck, I really haven't been looking..

Seriously, tho..thanks, dude. If I ever have slushbox troubles (SWMBO's bringing home a XJ40 Jag this week), I'll know who to ask. And of course, if I ever move to central TX, your place goes on the "trusted ally" shop list.

Zomby Woof
Zomby Woof PowerDork
11/3/10 9:30 p.m.
Jensenman wrote: One thing I learned over the years: lots of the manufacturers claim a 'lifetime fill' or '100k interval' transmission fluid. That is bullE36 M3. 60k max on ANY car, I don't care who made it or what kind of fancy fluid it uses. That's assuming no towing use. Towing, down to 30K max. Or, do like all the consumer advocate websites etc say, save yourself some money and run the stuff till the tranny blows up. Curtis and I will be very happy to see you. Oh, and also be sure to run the engine oil to the max interval for every change.

I had 2 friends that ran tranny shops. I asked their opinions (they didn't know each other) on OCI's for auto trans, and they both told me exactly the same thing. If it's working, don't touch it. It didn't make a lot of sense to me, but they stood by what they said, and I haven't had auto tranny problems in the 25 years since.

I always go to the max interval on oil changes, but my driving conditions are practically ideal.

wrenchedexcess
wrenchedexcess New Reader
11/4/10 4:28 a.m.

If your trans will accept a Dextron type fluid and have a problem with high heat you may want to try Allison automatic trans fluid, it is made for large diesel trucks and will put up with the high heat. We run underbed compressors and 7500 watt generators on the PTO's some as long as 16 hrs. non stop. According to Allison this fluid can be run until it turns completely black with no ill effects to the trans. I have used it on my 01 Sonoma pick up with no ill effects, actually it improved the shifting. (188K on the tranny) However the stuff is not cheap, runs anywhere between 8-12 bucks a quart.

81gtv6
81gtv6 Dork
11/4/10 9:42 a.m.

Another "Thanks" Curtis. We have gotten our first Auto car and they are black magic to me so knowing what to do and what not to do is a great relief. Now letting my wife talk me into an 06 Merc R350 is still something that keeps me up sometimes but what can you do.

ReverendDexter
ReverendDexter Dork
11/4/10 11:10 a.m.

Another tangent, but what exactly is different between Dextron and Mercon? What determines which a transmission should use (i.e. what determines what they say to use in the manual)?

Tranny fluids are still voodoo to me.

triumph5
triumph5 HalfDork
11/4/10 11:23 a.m.

IIRC GM considers the automatic on the "new" Camaro to be a sealed unit. No dipstick, only a rubber plug accessabile only when the car is on a lift, and it's atop part of the tranny's pan. It's supposed to be a non-service item for 100,000 miles. Or has that changed?

Zomby woof
Zomby woof Dork
11/4/10 1:40 p.m.

Our 99 Z24 was like that. It had a plug on the side that you could remove to fill, or check the level.

car39
car39 Reader
11/4/10 1:43 p.m.

I had shifting problems and burnt fluid at 60k on my gas F250. We flushed the trans, added an additive, no problems since.

bluesideup
bluesideup New Reader
11/4/10 2:16 p.m.

When you say "flush the trans" does that mean hooking the cooler lines to a reservoir and running until clean fluid comes out or or some kind of power flush? We have a Mazda5 that has had 30k drain and refills as well as a 93 Grand Cherokee with 211k on the original trans with 30k drain & filter changes.

internetautomart
internetautomart SuperDork
11/4/10 2:52 p.m.
ReverendDexter wrote: Another tangent, but what exactly is different between Dextron and Mercon? What determines which a transmission should use (i.e. what determines what they say to use in the manual)? Tranny fluids are still voodoo to me.

Dexron was / is GM's spec. Mercon, ford's
There are several different types of them. only the DEXIII and Mercon (original?) are the same. Later versions (Dexron VI, Mercon V) are different spec. There is such a thing a s universal fluid, it is 2x the cost and fully synthetic though. I use that in my vans (Dodges).

curtis73
curtis73 HalfDork
11/4/10 4:25 p.m.
wbjones wrote: along the same lines... question for curtis73: my '95 Impreza with 230k occasionally (especially after going up some very steep hills ... of which we have plenty here) gives off a faint burnt smell... fluid has been drained (no pan removal) and refilled every 30k since new... it's just now starting to shift pretty hard (sometimes) from first to second... what's the next step ? wait for failure..?? or is there some PM I can do to put off a rebuild ? sorry for the thread jack... we can now return to our regularly scheduled programing...

Are you sure its burning tranny fluid? Typically internally burning trans fluid doesn't smell, only if its leaking on the exhaust.

The hard shifting is usually something other than wear. Your trans is remarkably similar to the OP's, just an older version of the 4EAT. They are known to have valve body issues - sticking pistons, broken or weakened springs, etc. It should have four solenoids: 1, 2, 3, and A. A would also be called a pressure control solenoid. My first thought would be to find someone with a Genysis scanner (or similar) that can monitor OBD1 functions and see if they can verify the function of solenoid A. Then do a pressure test on the line pressure and see if its within spec.

I don't think the solenoids come separately, I think they come as a pack of all four.

I guess its possible that the filter is getting clogged and the solenoid is defaulting to full pressure, but I don't think 1995 Subarus are that "smart."

Try pulling the pan, cleaning it, put in a new filter and refill with some synthetic Dex 3 and a bottle of Lube Gard red (number 60902). That is the $70 stab at it. If that doesn't fix it, you're looking at valve body and/or solenoids.

curtis73
curtis73 HalfDork
11/4/10 4:31 p.m.

Dexron is GM's word. Mercon is Ford's word. ATF+4 is Dodge's word.

For the most part, anything 1993 and older can use Mercon 3. Anything newer should use either the specified fluid or a multi-vehicle synthetic. O'reilly has one called Global that works on almost anything 93-later. Auto Zone has one under their Coastal brand that is the same basic thing.

Many transmissions that call for something special (like T-IV for later Toyotas) can interchange with Dex 3 but they warn that "shift quality might be adversely affected."

Obvious exceptions to this are the more exotic stuff like anything with a ZF trans - Jag, BMW, Mercedes, Rover, and (of all things) Suzuki. ... or of course CVT trannys.

curtis73
curtis73 HalfDork
11/4/10 4:41 p.m.

At our shop we only stock one fluid. Its one of the synthetic blends and we buy it 200 gallons at a time. Its actually cheaper than buying quarts of Dex/Merc so we use it for everything except ZF and CVT.

wbjones
wbjones Dork
11/4/10 8:14 p.m.
curtis73 wrote:
wbjones wrote: along the same lines... question for curtis73: my '95 Impreza with 230k occasionally (especially after going up some very steep hills ... of which we have plenty here) gives off a faint burnt smell... fluid has been drained (no pan removal) and refilled every 30k since new... it's just now starting to shift pretty hard (sometimes) from first to second... what's the next step ? wait for failure..?? or is there some PM I can do to put off a rebuild ? sorry for the thread jack... we can now return to our regularly scheduled programing...

Are you sure its burning tranny fluid? Typically internally burning trans fluid doesn't smell, only if its leaking on the exhaust.

The hard shifting is usually something other than wear. Your trans is remarkably similar to the OP's, just an older version of the 4EAT. They are known to have valve body issues - sticking pistons, broken or weakened springs, etc. It should have four solenoids: 1, 2, 3, and A. A would also be called a pressure control solenoid. My first thought would be to find someone with a Genysis scanner (or similar) that can monitor OBD1 functions and see if they can verify the function of solenoid A. Then do a pressure test on the line pressure and see if its within spec.

I don't think the solenoids come separately, I think they come as a pack of all four.

I guess its possible that the filter is getting clogged and the solenoid is defaulting to full pressure, but I don't think 1995 Subarus are that "smart."

Try pulling the pan, cleaning it, put in a new filter and refill with some synthetic Dex 3 and a bottle of Lube Gard red (number 60902). That is the $70 stab at it. If that doesn't fix it, you're looking at valve body and/or solenoids.

actually it's OBDII... an early model of what was to come ? I've had it 5 yrs and the only codes it's thrown have been .. mis-fire #4 and cat (repeatedly)

as for the "burnt" smell I just assumed it was trans fluid... something has a slight burnt smell after a slow speed very steep climb ... think 40 - 50 ° hills...

thanks

car39
car39 Reader
11/5/10 7:47 a.m.
bluesideup wrote: When you say "flush the trans" does that mean hooking the cooler lines to a reservoir and running until clean fluid comes out or or some kind of power flush? We have a Mazda5 that has had 30k drain and refills as well as a 93 Grand Cherokee with 211k on the original trans with 30k drain & filter changes.

Hooking the cooler to a reservoir and running until clean

gmiller11
gmiller11
12/3/15 9:07 p.m.

I have a 05 Chevy impala I bought from a used dealer the car has not been in my possession 3yrs yet and only 13375 Miles on the car the check light came on took it the shop they tell me the transmission fluid is heavily burnt and causing the tranny to go bad yet I do not smell anything Burt and my car runs just fine . I need advice please

pres589
pres589 UberDork
12/3/15 9:19 p.m.

In reply to gmiller11:

You jacked a dead thread but it's a decent one so why not; pull the trans dipstick and look at the fluid. A white paper towel to see the color helps. Sniff the fluid on the dipstick. You won't smell burnt trans fluid without doing something like the above unless it's leaking fluid on the ground.

gunner
gunner Reader
12/3/15 9:40 p.m.

In reply to gmiller11:

Also take it to an autozone or other place that can run the check engine codes that doesn't have an agenda to sell you some service just to get a second opinion.

Spinout007
Spinout007 UberDork
12/4/15 10:14 a.m.

I've got one for the hive. Mom has an 06 Ford 500, when the go pedal is mashed hard the trans seems to shift into neutral. Not slipping as the engine free revs, as in up and down and when it reengages it is a herky jerky traumatic experience. No dipstick to check the fluid or fill that I am aware of.

Any suggestions?

1 2
Our Preferred Partners
nA59UDb1qzX2ONLOyvseLMPYgOLH05zf