Synthetic auto trans fluids
  • Register
  • Help
Results 1 to 23 of 23
  1. #1
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default Synthetic auto trans fluids

    Hey guys, I just wanted to find out what brands of synthetic auto transmission fluid people could recommend and where I can find the stuff.

    I had a search through the archived threads and found some discussion on Redline and Lubrication Engineers products, but I don't know where I can buy these. Looking through the shops today, I found synthetic fluids made by Penrite and Castrol and I believe a semi-synth formula from Motul. The Castrol Transmax Z was $60 for 4 litres!

    Any input would be appreciated. Oh, and FYI the tranny this fluid is to go into is our much maligned R25.

    Cheers,
    Richard

    Advertisement
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  2. #2
    Gone Fishin' Ray Bell's Avatar
    Join Date
    Jun 2001
    Location
    Burpengary and Murrumburrah, Qld and NSW
    Posts
    9,223

    Default

    Why are you so keen on getting a synthetic fluid... and does it use that at the moment?

  3. #3
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default

    I thought that a synthetic fluid could possibly extend the life of the transmission by cleaning things out a bit and reducing some of the wear. The transmission hasn't been very well cared for by previous owners and mechanics, so I'm worried that it could be on its way out.

    After I get the valve body back in and put the sump back on (I've been cleaning out the solenoids in an attempt to stop the tranny from skipping 2nd when driving in D), I'll have to put in some fresh fluid so I figured this would be a good opportunity to refill with something better. So far I've just been using Castrol Dexron III.
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  4. #4
    1000+ Posts Fordman's Avatar
    Join Date
    May 2004
    Location
    Perth/West Australia
    Posts
    1,382

    Default

    My 20 cents worth (as an ex-mechanic) is to use what you have been using before as long as it is the correct fluid for the transmission. It sounds like you haven't stripped the whole trans, so all the discs are soaked in Dexron and you shouldn't mix the synthetic with it. Also why put expensive (very) fluid in when it doesn't need it, and it sounds like you half expect it to require overhaul in the near future so you would just be wasting what you put in. Nothing wrong with Dexron III, and the fresh fluid may help it anyway.
    Cheers.

  5. #5
    who? when? huh? GTI124's Avatar
    Join Date
    Jul 2002
    Location
    Gordon, NSW
    Posts
    4,527

    Default

    We used Neo's full synthetic in the GTi6 and this appeared to smoothen the shifts a bit. In manual tranmission form the oil will last for the lifetime of the vehicle, I believe.

    Here is a link to the AT transmission: http://www.neosyntheticoil.com/atf.htm

    Paul Vassallo sells this in Sydney and you used to be able to buy it through www.autospeed.com

    Here's some information on AMSOIL's product: http://www.amsoil.com/products/atf.html

  6. #6
    Gone Fishin' Ray Bell's Avatar
    Join Date
    Jun 2001
    Location
    Burpengary and Murrumburrah, Qld and NSW
    Posts
    9,223

    Default

    I think it's much wiser to heed Fordman's warning about changing oils mid-life...

  7. #7
    1000+ Posts
    Join Date
    Mar 2004
    Location
    Melbourne
    Posts
    5,066

    Default

    Quote Originally Posted by silverexec
    I thought that a synthetic fluid could possibly extend the life of the transmission by cleaning things out a bit and reducing some of the wear. The transmission hasn't been very well cared for by previous owners and mechanics, so I'm worried that it could be on its way out.

    After I get the valve body back in and put the sump back on (I've been cleaning out the solenoids in an attempt to stop the tranny from skipping 2nd when driving in D), I'll have to put in some fresh fluid so I figured this would be a good opportunity to refill with something better. So far I've just been using Castrol Dexron III.
    Have yoy checked that the solanoids are working?
    You can mix your old fluid with synthetic as long as it is Dexron but best check with maker. I've done it but reverted back to Dexron III - much cheaper. Instead i added some Lukas auto. trans. addetive and this improved shifting. However, the proper fix is an overhaul and making sure the clearances on the clutchpacks are correct.
    JoBo

  8. #8
    Fellow Frogger! frogs4ever's Avatar
    Join Date
    Jan 2003
    Location
    Tasmania
    Posts
    392

    Default

    Quote Originally Posted by silverexec
    I've been cleaning out the solenoids in an attempt to stop the tranny from skipping 2nd when driving in D
    I'm not sure about the R25's, but I had an R16 auto (electronically controlled, with solenoids) which was playing up in a similar fashion. Asuming the R25 box is based on similar technology, if it is perfectly able to hold 2nd gear when shifting manually, I would suggest that the problem is with the electronic control unit (aka computer) rather than with the box itself. An overhalled electronic control unit from Delta Transmissions in NSW fixed the problem at a cost of about $80 - in 1990. On the R16 the auto shift selector lever is connected to that electronic box, not to the actual transmission.... Have a look underneath your R25 to find out whether it uses the same arangement. If your auto shifts properly in manual mode, I would suggest that there is nothing wrong inside the gearbox - asuming the R25 box is electronically controlled to the extent that the R16 was. This is logical if you think about it.
    2004 Clio Expression Verve 4sp auto -
    1984 Fuego GTX 5 speed (now a write off) -
    1976 504 GL auto (sold)

    French cars, Australian wine.

  9. #9
    XTC
    XTC is offline
    VIC: a fine driving state XTC's Avatar
    Join Date
    Mar 2003
    Location
    Location Location Location
    Posts
    8,566

    Default

    Quote Originally Posted by Fordman
    Nothing wrong with Dexron III, and the fresh fluid may help it anyway. Cheers.
    And funnily Dexron III isn't only for autos, some Toyota manual boxes run it (much to the suprise of everyone in the workshop).

    - XTC -
    You're not fooling everyone, or did you forget? .......




    '02 Peugeot 206 GTi / '07 VW Golf GTI
    Now this is a .sig
    AF'd in PER, MEL, SYD, ADL, CBR

  10. #10
    1000+ Posts
    Join Date
    Jul 2001
    Location
    Perth, Western Australia
    Posts
    6,248

    Default

    Redline is available from all Coventry's stores...if they're over your way. I agree with the advice about not mixing the fluids, though.

  11. #11
    farmerdave
    Guest

    Default

    Quote Originally Posted by frogs4ever
    I'm not sure about the R25's, but I had an R16 auto (electronically controlled, with solenoids) which was playing up in a similar fashion. Asuming the R25 box is based on similar technology, if it is perfectly able to hold 2nd gear when shifting manually, I would suggest that the problem is with the electronic control unit (aka computer) rather than with the box itself. An overhalled electronic control unit from Delta Transmissions in NSW fixed the problem at a cost of about $80 - in 1990. On the R16 the auto shift selector lever is connected to that electronic box, not to the actual transmission.... Have a look underneath your R25 to find out whether it uses the same arangement. If your auto shifts properly in manual mode, I would suggest that there is nothing wrong inside the gearbox - asuming the R25 box is electronically controlled to the extent that the R16 was. This is logical if you think about it.
    The r25 box uses a full electronic control in the 4cyl version, but the solenoid switching is on the same principles as the earlier gearboxes.
    Elf renaultmatic is recommended, the new renaultmatic d3 is a full synthetic.
    Farmerdave

  12. #12
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default

    Thanks for all the interesting responses. I'm a bit surprised about not being allowed to mix fluid types - you're basically saying that once a particular type of fluid is put in the tranny you can never use anything else ever again (except if it's rebuilt or something and it's totally dry again). I want to try different types of fluids as I'm sure some would perform better than others, but if I can't mix fluids then this will be a bit hard to do... After I removed the valve body, a fair bit more fluid came out in addition to what I collected when I drained the sump, so there couldn't be much more left inside and the effect of mixing would be reduced I'd think.

    Having said all that, do synthetic fluids really have benefits over mineral-based fluids in trannys or are manufacturers merely using the "synthetic" tag to attract unknowing people like myself to buy it thinking that it's superior in some way? Has anyone who's switched to synthetic experienced any really obvious differences in the way their auto behaves?

    Quote Originally Posted by frogs4ever
    Asuming the R25 box is based on similar technology, if it is perfectly able to hold 2nd gear when shifting manually, I would suggest that the problem is with the electronic control unit (aka computer) rather than with the box itself.
    I was going to start a thread in the Renault forum about this, so if people aren't happy with this being here then I might start one. The tranny doesn't shift into 2nd even when I try to do it manually, which is what led me to suspect the solenoids. I've taken them out and tried to test them but, and I feel really dumb to say this, but I'm not sure I'm testing them correctly - I've tried applying DC of various voltages across the terminals but can't seem to get the ball inside each solenoid to do anything. I vaguely remember something from uni about solenoids needing AC to operate, but I doubt that the tranny computer would be converting DC alternator/battery voltage to AC to operate these solenoids. Who's more up with how these things work?

    Cheers,
    Richard
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  13. #13
    Fellow Frogger! Jack Z's Avatar
    Join Date
    Aug 2003
    Location
    Gosford, NSW
    Posts
    302

    Default

    Richard,

    I switcehd to Castrol Transmax on our Volvo 850 Wagon after it had done about 150k and the difference was amazing (sold the car at 250k)... so much so that I got my father onto it for his ED Fairmont and it had done about 270k at the time.

    I put 5 litres of the recomended (non synthetic) fluid through the box first as a flushing agent (to get the fluid in the converter out) and then drained and filled with transmax.

    Both cars shifted better than ever and the improvement kept up after subsequent changes.

    Given the cost of rebuilding a 4sp auto I think the $60.00 is money well spent especially given that I was getting 40k between changes and even then there is absolutely no visible discolouration so I changed it more as a precaution than due to (apparent) need.

    Can't comment about mixing fluids execept to say that as with most things I have found if you switch to something better as opposed to something of lesser quality I can see no reason for any adverse effects.

    There are many engines out there that have run on mineral based oils for years that love going to a semi synth or fully synth so I can see no reason why an auto box would be any different.

    I have not used any other types but in my experience in both the Ford and Volvo the Castrol Transmax has been superb after about 100k of driving.

    I am also running it in our BX with ZF14HP box but have not done a lot of klms since we got it so can not comment one way or another yet, suffice to say that given other experiences I am confident it will be a good thing in th elong run and it does appear to have reuslted in smother shifting in the first 2k of driving.
    BX TZI Hatch
    BX TRI Hatch
    GS C-Matic

  14. #14
    1000+ Posts
    Join Date
    Mar 2004
    Location
    Melbourne
    Posts
    5,066

    Default

    silverexec, the solanoid work when you apply a dc voltage. I used 12v on the AD4. If they don't work through the wiring harness try as close as possible to the solanoid. That is right at the solanoid. I've changed one from a 'broken set' to another. I had an open close to the solanoid.
    You can mix ATF if you like but the spesification has to be the same or higher. Castrol DEXRON III can be replaced by Castrol Transmax Z from what i've been told by their technical department - and i've done it. No problem.
    You may also find that DEXROM III from another manufacturer e.g. FUCHS may or may not improve the quality of the shifts. Formulation with respect to the friction plates is the key. Usually best to follow manufacturers advice.
    JoBo

  15. #15
    VIP Sponsor David Cavanagh's Avatar
    Join Date
    Feb 2001
    Location
    Romsey, Victoria, Australia
    Posts
    4,819

    Default

    Richard,
    If you want the correct ELF Renaultmatic we stock it at French Connection.

    David.

  16. #16
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default

    Well I might as well try out a synthetic fluid and see what happens, the tranny probably couldn't get much worse... I shouldn't say that, but it sounds like a few of you guys have had positive experiences with synthetics so I'd like to think that ours wouldn't suffer from it.

    Dave, is the Elf Renaultmatic synthetic or the normal stuff? I might drop past on Saturday morning.

    Quote Originally Posted by JoBo
    the solanoid work when you apply a dc voltage. I used 12v on the AD4. If they don't work through the wiring harness try as close as possible to the solanoid. That is right at the solanoid. I've changed one from a 'broken set' to another. I had an open close to the solanoid.
    Hmmm, I tried 12VDC on both of the solenoids and nothing happened, even after reversing polarity. I could see some of the metal sludge on the balls shift around a bit indicating some magnetic activity but the balls didn't seem to move. Are the balls meant to shift in and out substantially when voltage is applied or do they move just a little, because I'm not seeing anything at all.

    Richard
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  17. #17
    farmerdave
    Guest

    Default

    Quote Originally Posted by silverexec
    Hmmm, I tried 12VDC on both of the solenoids and nothing happened, even after reversing polarity. I could see some of the metal sludge on the balls shift around a bit indicating some magnetic activity but the balls didn't seem to move. Are the balls meant to shift in and out substantially when voltage is applied or do they move just a little, because I'm not seeing anything at all.

    Richard
    They should move a bit if you look closely but it is hard to see a shiny ball moving. If you can see bits of metal on them, they probably won't be sealing/closing properly and could lead to all sorts of problems (separate from any electrical fault). Remove the solenoid plate and blow the solenoids out with air or whatever.
    Have you checked continuity/resistance from the plug in the sump?
    The feed signal (on a 4141) is 12vdc, I checked it last night.

    Farmerdave

  18. #18
    1000+ Posts
    Join Date
    Mar 2004
    Location
    Melbourne
    Posts
    5,066

    Default

    Habe you checked the resistance of the solanoids? On the AD4 it is about 55 to 65 ohm. Probably much the same on yours.
    This is checking from the cable terminals that plug into the computer.
    JoBo

  19. #19
    VIP Sponsor David Cavanagh's Avatar
    Join Date
    Feb 2001
    Location
    Romsey, Victoria, Australia
    Posts
    4,819

    Default

    Quote Originally Posted by silverexec

    Dave, is the Elf Renaultmatic synthetic or the normal stuff? I might drop past on Saturday morning.
    Yes it is synthetic Richard, I wont be there this Saturday but I'll let my brother (Steve) know you might call in.

    David.

  20. #20
    1000+ Posts
    Join Date
    Jul 2001
    Location
    Perth, Western Australia
    Posts
    6,248

    Default

    Quote Originally Posted by silverexec
    I'm a bit surprised about not being allowed to mix fluid types - you're basically saying that once a particular type of fluid is put in the tranny you can never use anything else ever again (except if it's rebuilt or something and it's totally dry again).
    Yeah, I must admit that my comment was made based upon the general presumption that you don't mix different spec lubricants/fluids, especially as you usually only get about half the fluid out of an auto when draining it - not the same as an engine. If others have had OK results I'd go for it.

    Stuey

  21. #21
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default

    I'll give it a go but I'll keep an eye on it in case there's any nasty side effects.

    Thanks for the advice on the solenoids - I cleaned them out tonight with mineral turps and finally figured out how they work! The copper ball is supposed to be able to revolve in its seat in the end of the solenoid, but mine were choked up with metallic sludge so they couldn't move. So I cleaned them with a small paint brush and used compressed air to dry them. I tried applying 12VDC again and this time they seem to be OK - they pull inside slightly and can't be moved when I tried turning them with my finger. Remove the power and they can then be moved again. Looking good!

    All I'm going to do now is clean the valve body and the sump magnets, and get a new filter then I should be ready to put it back together. I should be able to know if it works next week. Can't wait!
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  22. #22
    1000+ Posts silverexec's Avatar
    Join Date
    Jul 2002
    Location
    Melbourne, Victoria
    Posts
    1,001

    Default

    Just thought I'd post an update to this. Well, I month after my last post I finally had it all back together (with the original torn filter in place, just to see if the tranny works or not). I filled it up with ordinary Dexron III to test out the tranny and flush it before putting in the good Elf synthetic stuff.

    Reversed it out the driveway and started heading off. The car did drive and the gears did shift properly from 1st to 2nd then 3rd but they clunked pretty severely during shifts. After a while though, it went back to its old tricks and started skipping 2nd again, and even trying to select 2nd manually wouldn't get it to work.

    So, I think the tranny's stuffed. Haakon, because it's Rod's car, I'm waiting for him to decide what he wants to do with it - convert to manual or recondition the auto. Problem is he can't drive a manual (we don't have any manual cars for him to practice in) and he got his Ps learning in an auto so he can't drive a manual until he's off his Ps - unless he does another official driving test in a manual.

    I'm urging him to go the manual way, but he'll probably end up driving my car for the next year while I drive his...

    Richard
    - Richard

    Now: 405 SRI D70 '93
    - 2.0L manual
    Earlier: 505 GTi Executive '85
    - hence "Silver Exec"...
    25 GTX '86
    - manual conversion

  23. #23
    1000+ Posts Haakon's Avatar
    Join Date
    May 2002
    Location
    canberra...
    Posts
    8,747

    Default

    no worries Richard - just let me know as soon as you can.

    Would they really hassle you if they pulled you up in a manual car with an auto licence? Manuals are not rocket science to drive, in fact I reckon the auto only licence thing is daft - everyone should at least know how to drive a manual in case they have to.

    Oh well - let him have the Pug and you can have the manual R25
    Last edited by Haakon; 22nd November 2004 at 01:13 PM.
    I tried to drown my sorrows in alcohol, but the bastards learnt how to swim

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •