Hello to everyone . I posted it last week as update for topic about choosing ATF - but now think it more proper to do as a new post. So... about 6 mo. ago car began make some " zooming " metal noise somewhere under tranny/engine border area ( similar to dry bearing ), at first noise periodically come and go, always on cold start... then level began to be more loudly - and after car reaches working temp it will almost gone. Tranny was worked during those challenges as like nothing is going on at all - there no any leak, no codes, ATF level is good, color is acceptable w/out burnt odor... One day, back in July, when day temp got over 100 i was driving at 50 and suddenly got CEL and blinking transmission light all over as Christmass tree... car still driving normally and gear changed as usual, coolant temp show normal temp level... I immediately slowed down and next day decided to change ATF . Checked what CEL code i have - " Generic " P0740 : Torque Converter Clutch Solenoid Circuit - So, i changed ATF with Supertech DextronIII/Mercon and take a drive for a week. Old ATF come clear,a little dark - no deposits at all . I have been read somewhere that quality and level for this particular AISIN transmission critical and can make weird noise. Noise from undercarriage almost disappeared for that week with a fresh fluid ... then slowly come back - car still driving as should and no more any CEL or transmission code. Then i decided to do ATF change one more time " just in case " - this time i put Valvoline MaxLife High Mileage. Again, noise gone for week - then back again .... AND THEN IT HAPPENED: Last Friday morning on the way home from work i stopped at the stop sign - when green lite come, released brake and pressed accelerator pedal slightly as usual ... Car began movement very slowly with some jerking and shaking - and, of course, immediately i got CEL and all transmission lights began blinking ... What a nightmare i have those morning - supposedly 20 min drive take almost an hour... Got home, tired and so-o depressed after graveyard shift and plus car still in a trouble ... - went to sleep ... Next day i checked for CEL code - sure, again P0740... Now i have to make decision : go for Volvo original torque converter (cheapest Volvo Genuine TC (9143121) price from 1200.00... ) or for some aftermarket one...research show a couple of them. Car recently turned over 182000 on clock,passed emission back in march , as all older engines - when started cold produces some " sounds " that will gone after warmed up... If anyone ever have experience with aftermarket Torque Converters, would you, please, share your story. Must make some decision asap- everything in everyday life depend on only transportation i have. Especially job. Thanks.

I had many of the symptoms you describe earlier this summer with my '96 965 - a 150K mile well-maintained car. You can see my posts on this in the 960 section of the RWD forum. Because the car was always serviced at Volvo dealers, the trans filter had never been changed. Once I did this and cleaned a lot of gunk out of the pan, the transmission has operated properly for about 1,000 miles.
The OBD gave me codes touching on everything from the computer to the torque converter - since there are no codes for a clogged pump filter it was just guessing.
so my advice is drop the pan and replace screen before doing any major work like replacing TC.

Thank you, analogdad , for info - just couple days ago i saw your story and read it... and that was my " hm-m...maybe it was not TQ..." moment. Back in 2005 when i got this car with 99000 on clock - i dropped tranny pan - all clear, magnets clear and filter was ok. So i put everything back - replaced oil with Mobil1 Synthetic by " carousel " - 2 Qt out - 2 Qt in... and since that time only tranny maintenance was - once a week or so just checked ATF level. When car reached 155-160K i began to see some weird reading on tranny dipstick... too low or too high - but no leak at all, and exactly that time a lil-bit noise ( as u perfectly described in your car story ) began to show-up. Still driveability was perfect - and no any codes. And this summer " sickness " win... Last weekend my friend " audible forced " me to pull down pan from tranny - in his garage...so i obey my dear friend request... Pan down - no metal deposits on magnets or anywhere ( except there is one phillips screw at the magnet, no sign or scratches, with perfect thread... similar to one at the photo by red arrow ) - just dark grease-like thin layer all around of the pan bottom.Rubbed this substance between fingers - did not feel any small pieces of anything hard, just grease like stuff. Opened VADIS for info how-to testing S1, S2, SL and STH solenoids: S1, S2 and SL should read between 10 and 15 ohm, STH between 2 and 6. Tested, and results: S1 - 12.8 ohm, S2 - 12.8 ohm, SL - 12.6 ohm and STH - 4.0 ohm. Looks like they ok, no visible deterioration anywhere. Got idea to test them by 12 volt and see how they actually worked - but not sure if they use 12 volt or no ... and STH solenoid have 2 separate pins inside plug - resistance was checked between those 2 connectors ... and no idea what correct voltage need for each of them ... Maybe checking resistance is good enough and i am just overkilling this test...as usual in my life. Then i take out ATF filter ... well, it does not contains anything big or suspicious - but all area of filter grid was covered by thin layer of fiber like/fabric material ( maybe from clutch disks... almost like on laundry dryer filter, even layer) , plus there is 3 opening that covered around with cork style material - those almost flat and hard as rock . On past Monday i looked at rockauto for ATF filter - saw one for 1.05 ( closing ) and another for 1.40 or so ... Ordered both - got them on Wednesday eve by DHL - for total price less than 18.00 First time using rockauto, not bad.One made in China, another - Taiwan , both have oil pan gasket from rubberised kind of material. Local AutoZone show price 16.99 or so for one w/out pan gasket. Tonight will go back to my friend garage - make good clean-up, put back solenoids, oil filter, and pan, going to put Walmart brand ATF for now ... and may Lord give to all of us His endless blessings...

Hope new filter/clean pan solves your trans issue. Be sure to follow torque specs in refitting the screen & pan.

It worked - like a magic... No more noise from tranny, no more scary tranny blinking codes, no CEL warning, all gear shifted smooth and nice. I put cheap ATF for now, then late will flush it and replace with good stuff. Just dirty transmission filter, and what a story. Thank you everyone for help.

Nothing wrong with Walmart synthetic ATF. It meets the spec required. I did my last few flushes with it and it works fine. I flush them every 30K and never had a problem.

Take a look at this thread:

https://volvoforums.com/forum/volvo-260-760-960-28/960-p0740-code-15577/

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Keeping it running is better than buying new

Hi KlausC .
Thinking about solenoid as well ... but how to tell if it is a connector, a solenoid - or it is TC failing apart ? That is the question... Did not have in apartment parking lot any possibility even just open hood for a moment - and that someone eyes already watching what is going on and ready to report... like in a war zone...
Friend have garage - yes, i can open gear box bottom there - and if solenoid in need to be replaced , that mean car need to be in that open condition 'till parts arrived and everything put back - and tested. Can not be there more than a couple of days... At first have to make to his home ... very slowly and avoiding even smallest elevation of street. Have to try it ... still can not figureout if that noise from TC directly... Another interesting thing about parts - by VADIS - for 1998 v90 engine B6304FS2 and with AW30-40,43 -TC PARTS # 6843119, FOR 1997 960 with engine B6304FS and with AW30-40,43 - TC parts # 6843118 ... are they different - or just last digit only ? But today from online web page TC parts # are 9143121 and mentioned that it fit all years... Still thinking about TC as a main problem...

p0740-volvo code is at331- refers to the lockup function of the converter, not the converter itself. lockup is controlled by a solenoid in the valve body. you really need the factory tool to run the tests. a good snapon or other real brand of tool MIGHT be able to talk to the trans and run the test. good luck, chuck.

Good day to all.
Worked graveyard shift this week, as always ... not much done with car during this time , now is off and have time for ...next step... Did not done any tests yet - believe that TQ is #1 issue due to the terrible sound from TQ area location. Slowly can drive - shifted fine , no code yet... think to choose TQ brand ( REMAN ) and replace - and then see ...
Got some recommendation from another Volvo forum user to check online catalog from Transtar Industries - did not see needed part , send e-mail just in case i missed info if they have one that i needed. At the same time i can see that Rock-Auto web page has REMAN torque converter by DACCO - did not know about this brand ... and there is company out of Florida -(https://www.floridatorqueconverters.com/transmissions-volvo-AW30-40LE.html ) shown there is two converters and seems both should fit ( one is mentioned as a " high stall " while other one as a " low stall ...??? ). More : brand "
TORCO " - torqueconverter1.com that have one on my car at they ebay web page by # Manufacturer Part Number:V11 .
... ... and even more - https://www.makcotransmissionparts.com/TC-VO29.html ... What to choose - that will be next step, any helpful info about mentioned above sources will be greatly appreciated. Thanks!