AW55-50SN woes-easy to repair? Topic is solved

[renns]

Glad to hear it worked out for you. I got about 2500 km (1500 miles) on mine, before it started acting up again. I was hoping for more, but it did buy me enough time to shop for a replacement vehicle.

[evilcowboy420]

Glad to hear it worked out for you. I got about 2500 km (1500 miles) on mine, before it started acting up again. I was hoping for more, but it did buy me enough time to shop for a replacement vehicle.

Thanks mine went into limp mode so I cleared it and it started acting right. I installed the new filter and emptied and filled the fluid again. Hopefully it stays good for a bit, I am thinking when it gets warmer of just installing a used one. I am sort of expecting to have to pull the valve body again and clear it out of any debris from the hole in the filter and clean up the solenoids. With any luck the thing will hold out for me to get stuff done.

[evilcowboy420]

update to this epic trash transmission. So I cleared it again and it went into limp again. Then it started delay shifting, and banging into 4th gear. So now I take it the clogged crap from the filter ended up clogging the screens on the solenoids. So I am going to have to take the pan off. I still have my original solenoids and I couldn't find anything wrong with them so I guess I will just switch them out to save time cleaning.

Don't get me wrong. When the transmission works it works well but due to its monumental amount of things that can cause it to slip or bang around makes me feel like it could have been designed better. As a matter of fact filter is an utter failure as far as design goes. I have seen literally zero transmissions that could not be replaced on. Sorry but the best transmission design I have seen is Mercedes, there are simply not that many transmissions you drop the pan on and have access to the filter, solenoids and accumulators. Mercedes does and thats why they make a better transmission than this Japanese POS. I know this paragraph is mostly opinionated but its just my own experience with transmissions.

Back to this one though. I will keep updating with anything else I do to it so folks can build off of it and just know the possibilities of problems the may face when doing this modification and may be able to devise a shorter work around.

Also as a notation, do not put the wrong transmission fluid in this transmission. I am pretty sure I pulled dex III out of mine and it was a face palm moment of the century since I actually learned to read and can clearly see everyone on Earth says to put the 3309 compliant fluid in it. The person before me to drain and fill it had no business touching it if they can't read. Why this upsets me so much is the owners manual was still in the car with a hand written note in it stating the proper fluid for the car.

Hope this thread continues to help people because at the very least the car moves when it was not moving so in my mind that makes it worth the effort because it is acting a lot better than it did. Thanks to all who read and all who contributed to this post as this forum is by far the most helpful one I came across.

[vtl]

AW55-51 in Volvo outlasts Volvo engine IF it sees a fresh fluid every 30-50k and has extra ATF cooler. Heat and dirty ATF is what kills it.

[firstv70volvo]

Special thanks to Precopster, Cuhfs and many others in this thread for the inspiration to drill a hole in my not so perfect transmission.

My transmission filter was clogged with the pump whining and with me not yet being ready to pull and rebuild the transmission I thought I might use many of the ideas in this thread except for poking holes in the filter mesh. First I wanted to try and clean the filter and if I did decide to rebuild the transmission at a later date I didn't want unfiltered fluid going directly into the pump and valvebody. Valvebody was replaced a few years back and transmission shifted perfectly before filter clogging.

After cleaning the filter I'm very satisfied with the results and I'm confident of getting many additional miles out of the transmission before it needs attention again. Based on the results I will say the filter can be cleaned with very good results. If the transmission is not self destructing (and my trans doesn't appear to be) and putting a lot particles into the fluid I don't expect the filter will clog back up anytime soon.

Attached are my notes and photos of the results.


https://app.box.com/s/ahacprqhk1rkb6klp9nlzt7y0n6eevbb

[cuhfs]

Always great to see these cars survive

[zak]

Anyone aware of whether this procedure has been needed on later AW55 transmissions such as 2004 XC70?

Noticed there was a change in filter design in 2004, something about the addition of a "rib dam" in the filter design:
https://www.oregonperformancetransmissi ... creen=SRCH

[zak]

A second observation after reading this thread:

In this post zaq (no relation) discusses using the drilled in port to simply vacuum off the screen:
https://www.oregonperformancetransmissi ... creen=SRCH

In this post firstv70volvo noted that with the valvebody removed there is a passage leading directly to the topside of the filter screen:
search.php?keywords=previous+dealer&t=82841&sf=msgonly

Given the above, if one were planning a valvebody swap, wouldn't it be useful to drill a hole as noted here:

fill the filter with 3309 or possibly a nonflammable solvent, and use a vacuum with an inline drop out chamber to simply clean off the screen?

In this way the screen would still keep contaminants out of the passages of the valvebody and transmission, while avoiding pressure drop that would reduce line pressure or lead to pump cavitation/whine.

[vtl]

IMO when transmission started to trash filter with its internals, asking whether you should punch the filter is like asking if you should switch to a lighter beer because doctors found you've got a terminal liver cancer.

From what I read, 90% of all clogged filters is torque converter long gone. I have one from MY05 w/ 220k miles in my garage waiting for OPT overhaul kit: mechanics looks very decent, valve body is probably OK, but the ATF is black and sooty. It probably got caught early, the fine mesh in filter is more or less clean.

[cuhfs]

ZAK - certainly could try that but you'd have to take the VB off and then put it all back together to know if it worked versus the hole drill is a lot less work for a more certain result. If you are doing the VB anyway then it may make more sense. The inline filter or two (one on each line), plus the flush and new fluid can solve for filtering.

VTI - using your cancer analogy, doing the transmission punch on an essentially dead car is effectively a "nothing left to lose"' situation. Best case you get an extra 100K miles and it cost you 1 hour and under $100 for fluid and you celebrate with a light beer. Worst case zero miles and it cost you under $100 for fluid, skip the beer and hey you took a shot. I rather try and save'm when I can versus a DNR (do not resuscitate).