Neglected AW55-50 - Plan Of Attack?

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I recently bought a very cheap 2007 Saab 95 (£300 cheap!) with a leaky water pump. It's a 150bhp 4 pot diesel with an Aisin 5 speed box. Service history is non-existent and in the UK gearbox oil changes are almost unheard of. The oil on the gearbox dipstick is black, but not burned so I'm pretty sure it's the original oil with 134,000miles of service over 13 years. I've changed the timing belt, water pump and gave the car a thorough service including new brakes all around. 90% of the time the gearbox changes are quick and smooth with no complaints. However, I've noticed occasional shift flares when the gearbox drops from 4th to 3rd or 5th to 4th during acceleration. Weirdly, it doesn't do it when it's in sport mode. I must admit, I prefer it in sport mode as it locks up the converter as soon as it gets into 2nd and makes the whole experience feel less 'spongey'. Anyway, next week I'll be doing around 200miles a day and planning on getting out of my Volvo for the week and using the Saab. I'm planning on doing a drain and fill every day as soon as I get home in order to flush out as much of the old oil as possible. I'll be using a universal ATF much like MaxLife. I've got 20 litres of Comma MVATF Plus ready to go! I'm wondering if it's worth running some kind of solvent through the gearbox for the first drain and fill such as Seafoam to try and help loosen up any varnish or crud they may have built up. Anyone have any experience of this? I have noticed that Seafoam actually do an ATF specific product, does this mean standard Seafoam isn't suitable for ATF? Any advice appreciated! What would your plan be?
 

Astro14

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The Aisin AW55-50 suffers from Valve body wear. Specifically, the SLT solenoid bore, which causes a loss in line pressure as it wears. Various kits/services exist to repair this. For example: https://www.sonnax.com/units/491-55-50sn You can try a complete fluid exchange. Easily done via the cooler line. Any T-IV/JWS-3309 fluid will do. Personally, I've found that my local Toyota dealer is the cheapest source for T-IV fluid. Not certain what the options are on your side of the pond. New fluid will help this, and that's what I would do first... But it likely won't fix the problem. The real fix, usually, is a rebuilt/repaired valve body. If the soft parts aren't too far gone, you can bring this back. I've done this (valve body replacement) on all three of my Volvos. Wrote up the Volvo-specific procedure a decade ago. You can read through it here: https://www.volvoxc.com/0/resources/how-to/pdf/2002-V70-XC-Valve-Body-Replacement-Notes.pdf I will add that on my last time through this, I used (and adapted, via a swap of one solenoid and adding some wire) a brand new GM valve body bought on Amazon. https://www.amazon.com/gp/product/B0016IUWIA/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 You may wish to purchase the ATRA rebuilders guide, which I found incredibly useful. https://www.amazon.com/ATSG-AW55-50...w-55&qid=1579711826&sr=8-1-fkmr0 Finally, the last step for fitting a new valve body is the adaptation cycle. I've got a copy of VIDA (Volvo's proprietary software) and a DiCE (multiplexer) that allows me to put the Volvo TCM into adaptation mode.
 
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black & burnt fluid is obviously no good. ask yourself is it worth the trouble... if you were to sell it, just toss in a tube of Dr. Tranny Shudder Fixx and be done with it! if you really plan to keep it and you're a DIY'er and not use a professional flush service... (check out youtube videos of DIY tranny flush) WARNING: with neglected transmissions a D&F with new fluid may cause more problems as varnish, debris, old clutch material has new fluid to dissolve & disperse into, I would recommend at least 4 D&F's and change the filter. be very mindful and take notice of transmission behavior after each D&F, make sure each D&F gets a couple of heat cycles (30-300miles) in before doing another D&F - if it acts up, do another D&F. my drawn out plan successfully implemented here: https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/5329410/1 standard Sea Foam and Sea Foam Trans Tune have only minor differences in the proportions of it's chemistry per the manufacturer, both use the same MSDS/SDS, if you choose to add a solvent as a fast or slow flush, you do it at your own risk! sick your flare issue maybe addressed with fresh fluid or with an additive like Lubegard, if not, your transmission or its hardware (ie. valve body, solenoids, switches) are simply worn out. double check the Comma MVATF+ specifications with the specifications required for the Aisin. new fluid will result in new behavior, it could be good or bad LOL
 
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In this case, start doing a drain and fill. I checked the Comma stuff and it's suitable for the Toyota T-IV spec. Repeat this on 1K(1000Km) intervals until the fluid looks clean and red. Then replace the filter. See how the transmission feels when it shifts. If everything feels fine, do what Astro14 suggests as PM. I'm not a fan of universal fluids in Toyota T-IV applications, unless it's a high-viscosity fluid. I've had luck with Castrol Transmax Import Multi-Vehicle. since Castrol is part of BP, Transmax Z seems to be the crossover in the UK.
 

Astro14

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Hard to change the filter on this one. With the pan removed, you can access the valve body. To get at the filter, you'll have to remove the transmission and split the cases. I wouldn't worry about the filter until you've got this thing working properly. Once you do get it working properly, then I would plumb in an external filter. Here's an example of that on one of my Volvos. https://www.volvoxc.com/forums/showthread.php?27334-02-XC70-Transmission-Flush-From-Bottom Scroll down a bit, you'll see the posted pictures. Incidentally, that entire thread on Volvoxc.com is about flushing this transmission. OP, you may find the discussion germane.
 
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Originally Posted by discountdon
WARNING: with neglected transmissions a D&F with new fluid may cause more problems as varnish, debris, old clutch material has new fluid to dissolve & disperse into,
Old wive's tale that is told when a transmission flush is upsold and then smokes the trans.
 
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Originally Posted by maxdustington
Originally Posted by discountdon
WARNING: with neglected transmissions a D&F with new fluid may cause more problems as varnish, debris, old clutch material has new fluid to dissolve & disperse into,
Old wive's tale that is told when a transmission flush is upsold and then smokes the trans.
Totally agree. New fluid via D&F always makes them work better in my experience.
 
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Originally Posted by maxdustington
Originally Posted by discountdon
WARNING: with neglected transmissions a D&F with new fluid may cause more problems as varnish, debris, old clutch material has new fluid to dissolve & disperse into,
Old wive's tale that is told when a transmission flush is upsold and then smokes the trans.
It's when you add a chemical flush to the fluid that can cause issues. I'm a proponent of ATF only. Maybe Trans-X/AT-205 if you have a leak and Lucas if you're trying to unload a junker - depending on your morals.
 
Originally Posted by nthach
Originally Posted by maxdustington
Originally Posted by discountdon
WARNING: with neglected transmissions a D&F with new fluid may cause more problems as varnish, debris, old clutch material has new fluid to dissolve & disperse into,
Old wive's tale that is told when a transmission flush is upsold and then smokes the trans.
It's when you add a chemical flush to the fluid that can cause issues. I'm a proponent of ATF only. Maybe Trans-X/AT-205 if you have a leak and Lucas if you're trying to unload a junker - depending on your morals.
the risk exists when servicing a neglected automatic transmission regardless of no-flush or flush with chemicals (solvent/detergent/esters), most independent mechanics I've talked to won't touch them and simply refer to the dealership. failed transmissions after servicing: https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2860520&page=all https://mechanics.stackexchange.com...ing-transmission-fluid-in-older-vehicles
 
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Thanks for the advice. I'm going drop the fluid on Sunday night. I'll add a bottle of Seafoam HydraTrans to the first fill. I'll do a drain and fill every evening when I get back and on Thursday evening I will add a tube of Transgaurd to the fluid and see if it makes any difference. If It's still the same I shall maybe look at changing over to a genuine 3309 oil. This is a 3 year car, it's for my Wife to use. She only does 4-5k a year so it fingers crossed it will hold out for us.
 
Originally Posted by Bailes1992
Thanks for the advice. I'm going drop the fluid on Sunday night. I'll add a bottle of Seafoam HydraTrans to the first fill. I'll do a drain and fill every evening when I get back and on Thursday evening I will add a tube of Transgaurd to the fluid and see if it makes any difference. If It's still the same I shall maybe look at changing over to a genuine 3309 oil. This is a 3 year car, it's for my Wife to use. She only does 4-5k a year so it fingers crossed it will hold out for us.
double and triple check the fluid levels properly at each and every interval - and check sporadically during operation - as fluid will expand at operating temperatures let us know how it she goes, if it blows all the anti-additive peeps will blame shootme for promoting them popcorn2 godspeed OP!
 
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I've tended 5 of these and swear by fluid refreshments. I live in awe of posters who've changed their valve bodies. Nobody on these boards uses ATF change intervals as low 200 miles but given your "go power" and clarity of plan, who'd suggest lengthening your 200 mile plan? MUSE: My thought on that subject involves not knowing how readily the torque converter drains upon shutdown. In other words, would 200 mile intervals provide enough opportunity for fresh fluid to be pumped into the TC? Hey, if the original fluid is jet black and the second D&F comes out much cleaner you can rethink your schedule. I also swear by LubeGard (red bottle).
 

Astro14

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I think I would simply change the fluid - and ignore the solvent additives. You can't change the filter on this - so anything that you stir up with solvents, like Seafoam, has to stay in the fluid - and you're doing a drain and fill, so you're not completely changing the fluid, right? That means you will have stirred up whatever was in the pan, without removing it completely, leaving it running through those delicate passages and solenoids...not something I would want. The valve body failures and shift issues on this transmission often happen when the solenoids get jammed up with iron debris that sticks to the slightly magnetized plungers in the solenoids. I wouldn't want to stir anything up unless that fluid was being completely changed. I've done a complete fluid change many, many times on older transmissions, with ZERO problems. But I've never used additives, just the fluid. E.G. AW-42 in a 1992 Volvo 850. First fluid change at 150,000 miles. Old fluid was completely black. Completely. Black. New fluid went in via cooler line exchange. Transmission worked perfectly thereafter. This transmission is very sensitive to fluid level and it is finicky to set. Underfilled - Overfilled is a 200 ml difference, and the fluid expands considerably with temperature. Be CERTAIN that you get that set correctly after each time you touch the fluid. To Kira's point, you'll get complete mixing of fluid after only a few miles. By 200 miles, it'll be completely mixed. If you wish to do multiple D&F, then putting 20-30 KM or so on it is plenty to ensure complete mixing of fluid internally.
 
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