What do we really KNOW about ATF? [Archive] - SaabCentral Forums

: What do we really KNOW about ATF?


Eiron
18th February 2009, 04:16 AM
Any interest in a collection point for ATF knowledge?

Here's my experience:

Saab, historically, has discouraged the use of synthetic fluids in their vehicles. Originally this was tied to the higher cost of the synthetic fluids & the unwillingness to recommend longer use intervals for synthetics, thereby increasing the cost of ownership for the buyer. Some leeway was given when Saab started incorporating synthetic fluids during the "factory fill" of the cars & extending their use intervals.

I owned a 1999 9³SE automatic for a little over 8 yrs (10/00-12/08). The owner's manual calls for Dexron III, mineral oil based. I changed the ATF at 35k (6/02) with Texaco Havoline Dexron III mineral oil. It looked like crap. I then changed it at 42k (5/03), 50k (5/04), 60k (6/05), 72k (4/06) & 90k (7/07) with Mobil 1 synthetic ATF. The transmission worked perfectly until the car was towed away after an accident at 109k (12/08).

I now own a 2002 9³SE automatic (1/09). The owner's manual calls for Dexron III, mineral oil based. I changed the ATF at 60k (1/09) with generic "Dex III" mineral oil. It looked like crap. A week later I changed it with generic "Dex III" again. It still looked like crap. I then changed it two weeks later (2/09) with Mobil 1 synthetic ATF. So far, so good.


Here's what I know about ATF:

Due to GM's release of new Dexron IV synthetic blend ATF, no new fluid can be labeled as "Dexron III." It can only be labeled as "approved for use where Dexron III is specified." Most manufacturers have now revised their Dexron/Mercon labels to read "Dex/Merc" or something similar. If I wanted to use a mineral oil based ATF today, it would have to be one of these "Dex" products.

Dexron IV is a synthetic blend ATF & is not recommended for use where Dexron III is specified. Of note, its fluid properties (http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_Dexron-VI_ATF.asp) are different from Dexron III.

Mobil ATF 3309 is mineral oil based & recommended for use in 9³ 5-speed automatics ('03 & later). The approvals are JWS 3309, GM 9986195, VW/Audi G-055-025-A2, & Toyota T-IV/T4 & T-III/T3. Although not recommended as a direct replacement for Dexron III, Mobil Tech Support said it is safe to mix with Dexron III or use as a replacement. Its fluid properties (http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_ATF_3309.asp) are similar to Dexron III.

Mobil 1 Synthetic ATF is recommended for use wherever Dexron III or 3309 is specified. It is not recommended for use where Dexron IV is specified. Its fluid properties (http://www.mobil.com/USA-English/Lubes/PDS/NAUSENPVLMOMobil_1_Synthetic_ATF.asp) are similar to Dexron III & 3309. Being fully synthetic, it does, of course, have the benefit of significantly improved cold flow properties (along with all of the other synthetic oil benefits).


Please add your knowledge to this thread ....

busaboy
18th February 2009, 06:07 AM
GM is at least up to Dexron VI fully synthetic - I had it put in my '02 Chevy when I had the trans flushed.


The bottle says it is compatible with "...all GM vehicles with an automatic transmission, including those that use Dexron III..."

needafunride
18th February 2009, 12:24 PM
I am very interested in this topic currently as I am replacing what I suspect to be the original ATF in my 2002 9-3 SE. The four quarts I drained last night were nasty.:cry:
I was planning on using a Dextron III to do a DIY flush over a couple weeks.
I would be interested in using Mobil 1 Synthetic ATF in there if it was safe to do so using my gradual replacement method.
Has anyone else done the switch from 'dino' ATF to synthetic using the 3-4 cycle partial drain/fill method?
---EIRON - I could not tell by your post if you did a 'real' flush when going between the dino and Mobil 1 or the method I described above.

Ero
18th February 2009, 03:43 PM
If you read around, there are stories of mobil1 synthetic ATF destroying saab auto transmissions.
I wouldnt risk it and just use the mineral one.

busaboy
18th February 2009, 09:45 PM
If one looks around, one can find stories saying ANYTHING...

tdrudd87
18th February 2009, 11:03 PM
For what its worth, I have put about 10k miles on royal purple's maxATF. I did 3 drain/fill cycles on 500mi intervals. The stuff that was was there was nasty with no service records from the PO. Now it is still real nice looking, and the trans is running fine, maybe a little smoother than with the black stuff that was in there...

Anyone else running the royal purple?

edit: its a full synth that is rated for dex3 as well as 3309

Eiron
19th February 2009, 02:03 AM
I am very interested in this topic currently as I am replacing what I suspect to be the original ATF in my 2002 9-3 SE. The four quarts I drained last night were nasty.:cry:
I was planning on using a Dextron III to do a DIY flush over a couple weeks.
I would be interested in using Mobil 1 Synthetic ATF in there if it was safe to do so using my gradual replacement method.
Has anyone else done the switch from 'dino' ATF to synthetic using the 3-4 cycle partial drain/fill method?
---EIRON - I could not tell by your post if you did a 'real' flush when going between the dino and Mobil 1 or the method I described above.Hi needafunride, your plan sounds fine to me (based on what I know & posted above). I've always used the DIY drain-&-fill method. Did you use a vacuum pump or did you find a 24mm wrench to remove the drain bolt? I would recommend 2 d&f using mineral Dex III. That'll give you 75% new fluid before you start with syn ATF. After your 1st syn d&f, you'll have 50% syn, 38% new Dex III, & 12% old fluid. At that point you can do your next syn d&f at any interval. I'm doing my 2nd syn d&f after 10k mi.

Of course, this is only my opinion, not a "rule" or "fact" to follow.

Eiron
19th February 2009, 02:07 AM
If you read around, there are stories of mobil1 synthetic ATF destroying saab auto transmissions.
I wouldnt risk it and just use the mineral one.Yes, that's why I posted this! I believe the stories are mis-information. I also believe you're completely safe sticking with mineral ATF, but not at the change interval of 60k mi or longer.

Sleepy7666
19th February 2009, 02:39 AM
Eiron. I am not making my Mobil1 issues up. There are numerous occurrences of this happening with A/W Transmission in Volvos and Toyotas. My Saab mechanic friend, who would not lie to me, has seen the results. The was a Saab Bulletin about avoid synthetic atf. I don't think its all bad but I went from having a transmission to not having one. If you want me to I will tape a video in my car of the shifting. It was fine before the ATF drain. Its was red as can be but I had no transmission. I drained it out and refilled with mineral and lo and behold I had a transmission-It was rough but after I drained and filled twice more I had a transmission back. I had no metal flakes attached to my plug and no black fluid. It was bright red. Check out my old threads and you'll see my links. I do not want a petty argument in this forum.

Dylan

needafunride
19th February 2009, 11:13 AM
Eiron, I have both a vacuum pump and a socket that fits the 24mm plug. I chose to drain so that I could clean off the magnet - luckily it was not too bad. (The magnet was not bad - I expected to find a mastodon in the tar that came out!)
Based on what I have been reading on the forums I will just replace with Dex III for now. I have an issue with bucking in reverse and hope to not introduce any new variables into the equation (it is the scientist in me!). Once I determine the status of my transmission - that will determine what fluid I try next - maybe something like Auto-RX for transmissions as something to try prior to a rebuild.

Eiron
19th February 2009, 12:53 PM
Hi Dylan, I'm not suggesting that you're making anything up. As I mentioned in another thread, I realize you've had very real problems. What I'm suggesting is that your mechanic, while well intentioned, is not well informed when it comes to all the properties of synthetic fluids. You should be getting fault codes, & your mechanic should be following trouble shooting procedures similar to these (http://www.townsendimports.com/Saab_TSB_Folder/Saab_TSB_pdfs/440_2220.PDF). You have many issues occurring simultaneously on your car. Some of them may be inter-related. (I'm not saying they are definitely inter-related, only that it's a possibility.) You also suspected your transmission controller, correct?

I saw the links you posted previously. I have no ability to verify where the info in the various threads comes from, especially when only listed as "I saw this in a document," or "I was told that..." Don't overlook the fact that your first two links come from the 9-5 forum & are regarding different transmissions than what we've got. 3309 is not part of the spec for our transmissions. (3309 is for Saab A/W 5 speed transmissions (as identified on the Mobil spec sheet), so why reference it for a problem on a 4 speed 9-3?)

I also have no information regarding Volvo & Toyota transmission problems.

As I said, I started this thread as a collection point for ATF knowledge. Like you, I have no interest in arguing. What I do have an interest in, is verifiable documentation & source/cause failure analysis. Also, although I greatly dislike the business practices of the oil industry in general (& Mobil's obscene profits in particular), I do believe that a company like Mobil does everything it can to prevent problems from occurring due to use of their products. That includes dumping millions of dollars into R&D, & working closely with manufacturers (Saab being one of them). Nobody wins when it becomes a lawsuit.

Eiron
19th February 2009, 12:57 PM
... Based on what I have been reading on the forums I will just replace with Dex III for now. I have an issue with bucking in reverse and hope to not introduce any new variables into the equation (it is the scientist in me!). Once I determine the status of my transmission - that will determine what fluid I try next - maybe something like Auto-RX for transmissions as something to try prior to a rebuild.Sounds like a good course of action & something I would also do in your situation. You plan is definitely more cost-effective than a rebuild. If you end up having to rebuild anyway, then you haven't spent much & you've bought yourself some time.

busaboy
19th February 2009, 06:36 PM
Well said, Eiron!

DickinFallsChurch
20th February 2009, 10:27 PM
For what it may be worth, Saab USA recommended against synthetic engine oil for many years, until they discovered some with Saab on the label. They recommended against synthetic in their manual transmissions, until they discovered one with Saab on the label. They recommend against synthetic ATF--guess they haven't found one with Saab on the label yet.

I've been running AMSOIL synthetic oils in engines and manual transmissions for over 30 years now without a lube-related problem. I've been running AMSOIL synthetic ATF in my Saabs (and other cars) since AMSOIL introduced it over 20 years ago, not a problem.

I would not hesitate to use Mobil 1 synthetic ATF in the older Saabs, but (far as I know) it is not recommended for the newer ones which spec the 3309.
AMSOIL ATF works great in those, too. I have a shop using the AMSOIL synthetic ATF in all Saab and Volvo fluid changes, and they have not had a problem yet.

I believe the GM Dexron VI is a semi-synthetic. It is considerably better than the previous versions, but (again) I don't believe it is recommended where the 3309 is called for.

Ero
20th February 2009, 10:44 PM
My question for all of you is, why tempt fate.
A transmission rebuild for an auto is expensive. If saab explicitely says no synthetics, why bother with synthetics? Its not like you see trannies running on mineral fluid dropping out and dying, in fact of the few auto trannies that did die, a good amount were on synthetic ATF.

E.G. this thread: http://www.saabcentral.com/forums/showthread.php?t=148654

Sleepy7666
20th February 2009, 11:19 PM
I would run Amsoil in heartbeat as they stand behind their product. I actually have the information on my right hand side to become an Amsoil Dealer. I strongly urge just using mineral ATF, 3309, or Amsoil. The was explained that when you use the synthetic it is too light of a lubricant and the gears eat themselves when you use reverse. Reverse requires full pressure of the fluid. If the gears are not lubricated enough they will bend, grind and snap. I would rather have people err on the side of caution rather than be out of a transmission. 3309 is used for the 5 speed transmission and was stated would work with any older 4 speed transmission. I am currently receiving 1 fault code and had 2 other ones. I have P0730 atm. My transmission controller is working fine. It is the transmissions gears where the issue lies. If anyone would find it beneficial I will be home March 13th and have my original ATF sitting there. I can also tape a drain and refill if it would help anyone. I may end up swapping another auto in or installing manual. I finally found a job and will be able to do so in the next month. PoisonBeef has ridden in my car and will vouch for the violent lurching when it shifts at 30mph. The Toyota and Volvo use A/W transmissions and there is recurring forum threads in their respective forums of the similiar results with Mobil1 MultiVehicle Synthetic ATF. I urge you all to look at a google search. It may work for some but why risk it? I wouldn't as I don't have the money to blow if my transmission goes simply from $40 worth of ATF when if I bought $25 worth of fluid everything would be good. But thats just me. I won't impose my thoughts on others, and since the
general consensus is that a Saab Mechanic of 30 years and I (I've spent over 20 hours in research alone) don't know anything I will not being commenting further.

Dylan

busaboy
21st February 2009, 08:34 AM
The Dexron VI bottle claims it's fully synthetic. And, unfortunately, it COSTS like a full synthetic!

Eiron
22nd February 2009, 03:30 AM
Thanks Dick. I appreciate you adding your voice to the thread. I know you've been using Amsoil full syn products in your Saabs for decades (!!) & was hoping you'd relay your experiences. Can you add any approvals that the Amsoil fluids meet for the various transmission specs?

busaboy, which brand of Dexron VI are you using? Both the Mobil & Havoline versions are semi-syn. You're right, the Mobil spec sheet says it can be used in pre-'06 cars calling out Dex. It was a Mobil Tech Specialist who recommended to me against using it. However, since the fluid specs are different from both the Dex III & Full Syn versions, I feel better using the Full Syn in a Dex III spec'd tranny anyway.

ero, I don't believe it's a "tempt fate" issue at all. I believe it's a "knowledge" issue. (Well, to be fair, I also believe it's a "proper care" issue.) Regardless, as I said to needafunride, I don't think there's anything wrong with using mineral Dex. You just need to be more frequent in your maintenance habits since the fluid doesn't protect as well or as long.

Dylan, I understand your faith in your mechanic. When I have a problem I don't want to fix myself, there's only one shop I'll take my Saabs to. I trust the owner & his employees to take almost as much care as I would. Still, as good of a mechanic as he is, he doesn't know or trust synthetics. And I'll never convince him otherwise! Is your mechanic providing your statements on synthetics?

3309 is a mineral based fluid but is not spec'd for our cars. Mobil Full Syn is approved for both Dex III and 3309 applications. You're saying a non-spec mineral fluid is safe to use but a spec syn fluid isn't?? Why?

You (or your mechanic) say that syn fluid is too light (http://www.machinerylubrication.com/article_detail.asp?articleid=707). If you review the fluid specs I linked at the start of this thread, you'll see that there is miniscule difference in viscosity between Dex III, 3309 & Full Syn ATF fluids. In fact, the only GM-use ATF that is lighter is Dexron VI. That's the one I listed at the start of this thread as being not recommended (and busaboy pointed out that the label says it's OK). The other thing you (or your mechanic) are not aware of is that syn fluids actually provide better film strength than mineral fluids. This means you'll actually have better gear protection using syn (http://www.machinerylubrication.com/article_detail.asp?articleid=167).

Again, I really do believe you're having transmission problems. If exchanging syn ATF for mineral ATF clears things up, then that's the correct thing to do. Aisin-Warner makes a lot of different transmissions & I don't have the time or interest to research Toyota & Volvo problems.

This thread is not meant to call attention to any one person or problem, & has not singled anybody out. It is only intended as a data collection point.
However, I believe open discussion about ATF fluids is useful & should be encouraged in this forum and this thread.

busaboy
22nd February 2009, 09:27 AM
Please note I said I am using Dexron VI, not Dexron IV - and it's GM's "brand."

FWIW - re: mechanics and others with opinions - I had a very good mechanic who worked on my VW for years. He refused to use multi-vis oils because he "...couldn't understand how they could work."

No one is perfect.

Eiron
22nd February 2009, 02:55 PM
;oops: Oops, thanks! I guess I need to write these things earlier in the day! :lol: