Hello,
Whilst I have gained plenty of great information from BITOG I have a query that does not seem to have come up in any detail. So here goes a lengthy post number one.
Below is the text I posted on my 'home forum' however this is an oil specific question so I figured my question might best be answered here.
At 75000km as an act of preventative maintenance I took my 2012 Ford Kuga 2.5 with AW55-51 AT to a gearbox specialist who has been doing business for a quarter of a century.
I had not researched what oil needed to be used but left it to the garage since I was sure they’d dealt with this box and its requirements before.
Fast forward 2 weeks and I ask the garage out of curiosity what oil they had used. The answer is Fuchs Dexron III.
When I Googled Dex III and AW55 transmission there were many posts regarding how this is the incorrect spec and how one should use JWS 3309 spec oil available from Mobil, Toyota and Volvo to name a few.
The AW55 manual appears to warn against it’s (Dex III) use.
I covered 1000km or 600 miles in the interim and am a little concerned about any damage that may have been done. Shifts are slightly less smooth and the Torque Converter does not appear to be locking up like it was. Fuel consumption seems to be up a little too which could be explained by the above. Two specialists say it is very unlikely I’ve damaged anything. (easy driving, haven’t been towing, largely freeway driving)
I have found Volvo oil – Part 1161640 which is approved for use in AW55 transmissions. It is not ridiculously expensive at £25 for a 4L bottle. There is no Mobil 3309 in this country.
I have been told that no method will completely remove the Dex III from the Torque Converter so there will be some residual Dex III in the new 3309 fluid. (By this reasoning there is still some residual Ford/Volvo 3309 in the current Dex III) It has been recommended that I have the box taken out, the coolers and TC cleaned out and then fill with 3309. Labor is £250 for this.
So my questions are as follows:
- Do I just run 16L of 3309 through the system at the gearbox garage who have the correct machine and remove most of the Dex III?
- Do I remove gearbox and clean completely, then fill with 3309? (More than twice the cost of option 1)
- Is it a disaster if after flushing there is maybe 10% Dex III 90% 3309?
My objective is to not spend the next couple of years second guessing whether or not I made the correct decision at this point in time.
Any thoughts on this would be greatly appreciated.
Whilst I have gained plenty of great information from BITOG I have a query that does not seem to have come up in any detail. So here goes a lengthy post number one.
Below is the text I posted on my 'home forum' however this is an oil specific question so I figured my question might best be answered here.
At 75000km as an act of preventative maintenance I took my 2012 Ford Kuga 2.5 with AW55-51 AT to a gearbox specialist who has been doing business for a quarter of a century.
I had not researched what oil needed to be used but left it to the garage since I was sure they’d dealt with this box and its requirements before.
Fast forward 2 weeks and I ask the garage out of curiosity what oil they had used. The answer is Fuchs Dexron III.
When I Googled Dex III and AW55 transmission there were many posts regarding how this is the incorrect spec and how one should use JWS 3309 spec oil available from Mobil, Toyota and Volvo to name a few.
The AW55 manual appears to warn against it’s (Dex III) use.
I covered 1000km or 600 miles in the interim and am a little concerned about any damage that may have been done. Shifts are slightly less smooth and the Torque Converter does not appear to be locking up like it was. Fuel consumption seems to be up a little too which could be explained by the above. Two specialists say it is very unlikely I’ve damaged anything. (easy driving, haven’t been towing, largely freeway driving)
I have found Volvo oil – Part 1161640 which is approved for use in AW55 transmissions. It is not ridiculously expensive at £25 for a 4L bottle. There is no Mobil 3309 in this country.
I have been told that no method will completely remove the Dex III from the Torque Converter so there will be some residual Dex III in the new 3309 fluid. (By this reasoning there is still some residual Ford/Volvo 3309 in the current Dex III) It has been recommended that I have the box taken out, the coolers and TC cleaned out and then fill with 3309. Labor is £250 for this.
So my questions are as follows:
- Do I just run 16L of 3309 through the system at the gearbox garage who have the correct machine and remove most of the Dex III?
- Do I remove gearbox and clean completely, then fill with 3309? (More than twice the cost of option 1)
- Is it a disaster if after flushing there is maybe 10% Dex III 90% 3309?
My objective is to not spend the next couple of years second guessing whether or not I made the correct decision at this point in time.
Any thoughts on this would be greatly appreciated.
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