AW 55-50 Transmission Glad to help!
 

I am amazed to see that all over the world through the different volvo forums ive come across this transmission has been the bane of so many! well I have had my love affair with this transmission for quite some time now, in fact it has been an obsession. all I can say is....... there is always a solution. fire away il be glad to help out as best i can and save you a lot of trouble.:lightbulb:

In England we can buy any number of Volvos quite cheap due to having a faulty AW55-50SN and there are lots of them on the road with faulty boxes where the owners just keep running them , I have a 2001 V70 2.4T which I bought for spares but I want to get it running properly again . Do you think that an amateur mechanic could take one of these apart and rebuild it without having specialist equipment ? I am willing to risk trying because there is nothing to lose because if I cant get it working right then I will use the car for parts but I am told it cant be done . One problem I see is there are parts suppliers in USA and one or two in Sweden but they want to sell complete kits of parts when you may only need one clutch band or one small part which they wont supply on its own . This box used in the Volvo I am told is very similar to those used by Toyota / Vauxhall / Nissan plus others but how similar is it , can you directly interchange all the parts because if this were possible it should mean the parts could be sourced cheaply , do you have a good parts supplier ?

Hi,
first you have to describe whats going on w/ the gearbox? is it shifting hard? slippinig? what gear? does it happen often or once in a while?... with regards to your other question , if you have the spare time there is no harm in opening up the box, it can be done, but it does need some form of specialized equipment if you might call it that. im refering to the volvo diagnostic equip. so you can reset adaptation values for the TCM. in my experience these boxes even when they dont run anymore rarely burn their clutches & band which is what conventional diagnosis and thinking might suggest. as a further suggestion I would recommend doing a pressure reading first and il help you interpret the readings. it gives a significant description of whats wrong inside. yes this box is used for many other makes usually you can interchange the hard parts ie. planets & drums also linings. the only thing to watch out are the solenoids some makes use different configurations ie. normally open & normally closed. Automatic chice in europe is a good source for parts ive got some from them and im half a world away.

The auto tranny on my 2004 base model V70 2.4 non-turbo 168 hp is an AW55-51 S as best I can read the metal tag. This is a 5-spd auto, but without the 'Geartronic' shifting. So do I have it right that this tranny has not had the troubles the Geartronic ones have had?

hi,
you have the upgraded ones,. but on a side note the aw 55-50's geartronic or not suffer the same problems especially the 2001 -2003

Hi
Do you know what is happening to my gearbox please, its a 2001 AW55-50SN that, only sometimes shifting up from second to third will let the engine rev to about 4/5K rpm and then change with a mighty clunk and then for the rest of that journey the gear changes will be sluggishly erratic. Once the engine has been restarted everything is fine again.
To be honest I'm not that worried about it as it only does it maybe once every two weeks but I would like to know!
Thanks in advance.

I think that will be the valve body.

What happens in that case, from what I understand, is:

1. TCM requests second gear disengage and third gear engage.
2. Pressure valve moves, gearbox disengages.
3. Pressure valve moves, third gear engaged.

(Not sure which valves are involved, although I think from what I recall 3rd gear involves the well-known B4 solenoid.)

If you get a delay between (2) and (3) above, then the gearbox will be in neutral for a time and the engine free to rev up. This can be caused by old fluid causing the valves to stick, or some other valve body problem. The B4 servo cover is also a problem on 2001 boxes, serial numbers around 01C-01L (March '01-December '01 build date) if I've remembered correctly.

The danger is that the sharp "lurch" is two bits of gearbox moving at very different speeds coming together - a bit like revving up the engine then dumping the clutch in a manual. It's what, over time, helps cause the entire box, rather than just the valve body, to die.

btw, have you had the B4 servo cover checked out? It's a known issue on 2001 models, and 2-3 shift flares are one of the most common symptoms for it having failed. Dead cheap part, saves replacing an entire gearbox later.

I've just been reading 'bout the B4 Servo Cover problem experienced with some 55-50SN box's & wondered if mine hade the matching Serial Number.

Info on my box is, 55-50SN, 9480902, SN 00KV717736

I just wondered if anyone could tell me how this information reads?



I copied this from a B4 Servo Cover thread;



So looking @ the SN on my box it looks like it was made prior to the ones with the doddy B4 Servo Cover?!:)

Can this info be relied upon?


Regards


Steven

I have also wondered about this. I have a July 2000 V70 and the 2 to 3 gear change can be a bit slow to changed up the first time I run the car from cold. The ATF has been replaced and the box seems fine a part from this.

Regards

Karl

Does it behave itself once the car's warm?

On these boxes there's a "catalytic convertor protection/warmup mode" which delays upshifts until the engine reaches a certain running temperature, which helps the cat get to temperature earlier and prolongs its life/improves fuel economy.

It's actually nowhere near as bad on the Volvo as my old (four speed auto) Omega with a similar setting, which I swear had a thing for making me look a right idiot on winter mornings as I went roaring up the road with the engine at about 4000RPM in first. :-)

Well it behaves itself after the first 2 to 3 gear change.

The 1 to 2 gear change is fine then the first time it changes 2 to 3 it wants to rev to about 2,750 rpm, everything OK after that until it's cold again.

I've had my 2005 D5 for 7 months now. Now the honeymoon period is over i notice that mines a right arse (not difficult, but not smooth) to go into and out of P. Is this the design of the box. All other gears & changes are silk. Car has 78k miles. A;so would the box survive if i got it chipped?

AW 55-50 hard shifting
 

Hi Guys...

I've got an '04 C70 whose transmission has been shifting hard lately. Mostly on the down shift (decelleration), but now it's doing it on the up shift (accellerating).

AT fluid has recently been changed, but performance has not improved. Maintenance Manuals are not readily available either... (at a reasonable price).

Got any ideas to share?


R2

:pizza:

hi,
have you got any codes? dtc's present? it would be a good idea to start with that,.. if you dont get any try to observe if it gets worse while the engine has been driven for a long time /normal operating temp or does show up when it still cold or it doesnt matter both? also did it improve when you drained or flushed the transmission?

Someone offering help on the AW55, COOL.

Let's start off by saying: I'm not sure I HAVE the AW55, as the computerscreen at the Volvodealer showed "AW50/51" iirc.

Just ran outside and the box itself says on an "Aisian AW" sticker: 55-51
03LV706106
8675 147 (these two numbers are under eachother, therefor I placed a [space] between them).

Problem I have is a message in the dash reading : transmission service required (it's actually the Dutch version, so this is not literally what it says!)

Symptoms:
- the "D" in my display disappears and a 'minus-sign' takes its place,
- the power is (...even...) lower than normal, especially in getting rolling/getting off the line
- I am missing 5th gear,
- the geartronic manual function is not available anymore and
- the cruise control indicator turns ON, but the function itself is not available.

When hooking up my recently acquired ODB reader I get P0748, "Pressure control Solenoid "A" electrical"
Also some other codes, but lets stick with the P0748 for now... :)

Any thoughts to what specific problem this is?
I want to check all connections of the solenoids (which one specifically?), but I do not know where to find them exactly, so help is appreciated (if needed I could remove the air-box this weekend?). I tried to have a look just now, and there appear to be some wires coming out of the box and connectors that are between the radiator and the air-box/EGR return elbow thinghy. May post a pic up later. (But beware I have a LHD, the (UK) description for changing the transmissionfluid I did 2 days ago called for the drainplug to be obscured by the rear-brakelines, but on my car they are nowhere near the drainplug :). This drain/flush with 14 liters is afaik not related to this issue, but had been planned since before the issue arose. The issue was there before and after.)

Someone linked this and I located the thinghy in the first pic that sticks out to the front of the car that seems like a cover. Is this where the solenoids are hiding? Can I simply unscrew this cover and the solenoids (apart from the 3 that are matched to the housing and should NEVER be removed according to this paper) and thus test them?

Help is VERY, VERY much appreciated!!!

http://img297.imageshack.us/img297/4...codesvolvo.jpg

One of the common issues with this box is the delay to engage drive. When cold it is almost instant ......... when hot, going from either reverse or neutral to drive has about a 2 or 3 second delay and the drive is taken up with a thump. However, when a restart is made (i.e engine off, engine on) then it will engage drive instantaneously (i.e. no noticeable delay). It could be a sticking solenoid, but the fact that it never occurs on a restart makes me think it is software related.

......... I think that this maybe something to do with the adaption settings and I keep meaning to have them reset when I have the time.

The delay issue causes no codes, no fail indication, and has been like it for the last 25K miles. I have changed the fluid and this made no difference. The car has done 76K

s60 with the same Deceleration hard shift at about 5 mph. Sometimes.
If i erase the "check engine" light it runs smooth. 90% of the time the s60 runs SMOOTH. sometimes it has the hard down shift.
2001 s60 base model non-turbo.

thanks from hawaii

aw 55-50 issues
 

Greetings all have a 2001 y plate V70 T5 AUTO not tiptronic , had in local auto trans specialist for a code read and oil change , only code was a slipping clutch sinse then drove only about 100-150 miles and now nothing .The car started to really struggle to get up a hill then when I thought it was ok again had total loss of drive .Had to get car recovered and is now sat on my drive. The car will start no problem and will on occassions go into all gears but only for a few seconds and then nothing . Any thoughts would be appreciated thanks Ian

Aw 55-50 sn
 

Hi you say you had the ATF changed recently what ATF did they use?
If you put anything but JWS 3309 spec ATF in these boxes it can cause serious problems.
Check your invoice or ask them quietly what they if they used Dextron you could have problems.

adaptive settings?
 

HI,

Thanks for that attachement on the AW55-50.

I have a 01B serial number? I have the exact symptoms below (lifted from the attached doc) - which have been intermittant which has led me to believe that this is electrical;

Description: This transmission relies on adaptive data to properly adjust the shift pressure. If the adaptation is not complete, it may result in one or more of the following:

• Harsh flare. Engine RPM will increase during a shift. This symptom feel like the transmission has lost drive. It usually happens during the 2-3 shift.
• Harsh down shift. Bumpy down shift when the gas pedal is odd (Zero).
• Harsh Garage shift. Sever bump when engaging forward or reverse from park or neutral.
• Harsh engagement control. After coming to a complete stop in drive, with the foot on the brake, the TCM waits for 2 seconds and then disengages drive to reduce emissions. This disengagement is not usually felt by the driver. If adaptation is not complete, then a “thud” will be felt. A harsh re-engagement will also be felt.

Any one got any advice? I will try to reset the adaptive settings, but unsure if this is all it will take, or whether this will re-occur.

ALso, I broke two of the orange rubber gasket seals on the electrical connectors from the Tranny when inspecting (to clean contacts and investigate). Any hints as to how to replace these - if needed?)

Was also wondering whether the B4 servo cover was easily replaced, or is it an engine out job?

Many thanks

B4 Solenoid
 

The B4 Solenoid is a fiddle to do but not difficult Volvo sell the repair kit (they call it a piston repair kit Rufe on here can help Doves if your desperate) its not expensive about £15 I think.
I used to have several V70 P2 in my business we had the flaring between 2/3rd changes on 3 of them as a precaution we changed the B4 cover on all 6 I also got into the habit of flushing the ATF every 50k after reading up on the American Forums (year was 2002).
You will need room to work under the car so up on stands or ramps. Take off the under tray M10 bolts if I remember.
At the rear of the transmission angled down you will see a large (about 60mm dia) cap with a raised cross on it, this is held in by an internal circlip. Remove the circlip access is tight but you can reach. With a large pair of grips rotate the cap using the raised cross the spring pressure will push it out, have some rag ready there will be a dribble of oil if the piston comes out push it back in.
Inside the cap you will see a hardened washer if this is loose or has come away that is your problem.
Use transmission fluid to lubricate the "O" rings on the new cap and push it in fit the new circlip, clean the area run the engine and check for leaks. Replace the under tray job done. Myself and one of my engineers became pretty quick after the first couple.
Finally Flush the Transmission then go to Doves to have the fluid counter reset and software upgraded. My understanding is you should only need Adaption if you have had major surgery on the gearbox.

When I sold the business I kept 2 of the cars and one of the engineers took one to be his personal car he is now over 250k and pulls a caravan?
So with good maintenance these boxes are tough.

Have you had the codes checked to make sure you don't have other issues?? You are not far away and I have a reader if you don't?

Just read the codes myself, there seem to be 2 p codes from the transmission module;

P0705 - Transmission Range Sensor A Circuit (PRNDL Input)
P0810 - Clutch Position Control Error

Also, when I scanned the Volvo specific code I also got these two;

0039 - Gear Shift Position Sensor Faulty Signal
012A - Neutral Check Faulty Connection

(are these the same issues reported differently by the reader??)

Any hints on these issues? Are they related to the shifting problem.

Also would like to know how/if I can reset the adaption, and the emmisions warning light on the dash with the reader (EU702)

Thanks

Gearbox
 

The EU 702 has a page which reads something like
Read Codes
Store Codes
Erase Codes
Just scroll down to the erase codes and press OK light out. Remember if you haven't repaired the fault it will come back.

Regarding the Volvo specific codes they indicate poor connections, have you tried unplugging the main transmission harness on top of the box and cleaning the plug and socket with electrical contact cleaner?
The see if it improves things.

With the EU 702 you can store codes in the reader for reference later

0039 indicates a fault with the PNP switch on top of the gearbox

012A could be one of the following:

Shift solenoid S1 has jammed in the OFF position
-Shift solenoid S2 has jammed in the ON position
-Solenoid SLT has jammed in the OFF position
-Internal fault in the gearbox
-Defective control module.

It is to do with the automatic neutral selection when halted for a while.

I think you need to investigate the connections to the PNP switch and possibly replace it.
For the second fault I'd start with getting the software updated to get rid of the neutral function, this may well get rid of the problem.

thanks, I cleaned the four connectors in front of the air box, front right of the engine compartment above the tranny (cables run back to the tranny), which seemed to help - although lost the orange rubber seals, which disintegrated on two of them, causing greif in reconnecting the connectors.)

Can you be more specific which one is the PNP switch? I have concerns about one of the contacts - looks a bit suspect.

Thx

Here's a link for the 850, yours will be similar.

http://volvospeed.com/Repair/pnpswitch.php

Keep this car or sell it
 

My 2001 2.4T, 137K mint condition, wife drives it displayed this message:

Trans service required

my equus obd reader said: P1619 Fault...AW 50-52...

So I took ti to jiffy and for $120 they flushed the trans, torque converter and put new oil.

Reset the obd and the car runs ok but it still kicks on downshift and gear engages and slips at the light.

So..I called a used volvo place and the part number is:
Transmission Part No : 9480902

Now the KICKER.
The seller says:

I give lifetime replacement warranties on most of my inventory.
However, this particular transmission comes with a 90-day parts warranty and sells for $1175.

So that means that this transmission is defective even I get a repalacement one.

So what is my best plan.

Best
Ashok
Valley Forge, PA

Volvo V70 2.4T 2000 Transmission 55-50SN
 

Got a 2000 V70 2.4T with none geartronic automatic code 55-50SN and serial starting 99J with a strange issue. Vehicle drove fine with no issues up until battery flattening (not completely flat but wouldn't start car). Jumped off another vehicle and car started and was given a good run and battery gained charge and no issues. Car not driven for rest of day but then next day autbox now clonking into drive on occasions and is rough changing. I've taken vehicle to trusted transmission specialist who tested car for a while and believe the valve body requires replacement. A Volvo specialist then had a look and came to the same conclusion.

Problem is the car is intermittent with the problem and at times drives fine, but then can rough change, and very occasionally can lose drive altogether for short period. Been reading about the B4 Servo cover but are these affected and if so how do I go about examination.

Hi Sidmon,

The box is controlled by one of the electronic 'brains'. This could have been confused by the low battery problem. It is worth resetting this and getting it to re-learn. I understand it can take 4 or 5 days to re-learn?

To reset this either means a visit to the local dealers or alternatively disconnect the battery for around 24 hours. Remember to use Volvos method of re-connecting the battery. See atachment.

It’s worth a try. Cheaper than letting the spannermen loose....

Bob

4t65ev
 

Hi there,
Would you have any idea about the above Auto box.? Starts off brill when cold, then when hot goes into "Limp mode", sets off in third, won't change up to 4th, Turn engine off, then restart works ok for 5 mins then back to limp.
Has selenoid "A"performance stuck off, performance on code reader.
Any help appreciated.
cheers,
joe.

Changed the B4 Servo cover but to no avail. Gearbox drives fine when cold and also when at speed on motorway but once gearbox has got hot and is on a stop start run it "bangs" into gear which literally feels as if you've been hit from behind (it's a horrible feeling!).

Is the box scrap or is there something I can do?

Have you changed/flushed the fluid?

No but the colour looks OK and I'm just wondering if it would sort a problem like that? I know your thinking you've got nothing to lose by doing but I don't want to throw more money at something to find it's made no difference!

Others have reported improvment by having the software updated to remove the stop/neutral function, have a search, don't think it's expensive.

I'd suggest that replacing and flushing the fluid would be a good idea as well. Fluid may look OK on the dipstick but I think you will be surprised how black it is once drained. Should not cost more than about £70 if you can DIY and use Vauxhall fluid.

The car is question has 12k miles on it and was main dealer serviced upto 108k and 2008...wouldn't the software have been updated by them? Has anyone else had the "shunt up the rear" transmission effect (sounds rude I know!).

Being a 2000 and a very early Phase 2 V70 it shouldn't have the stop/neutral function from what I've been reading, only 2001 and 2002 models??

fed up with it now
 

well i have one of the 2001 s60 2.4t with the gearbox problem
i have posted up before about it but to sum it up its now been over 14 months with the car going back to the main dealer, rebuild of my box and new torque converter, several trips back with problems, box back out 3 times and rebuilt, last time a new second hand rebuilt box was fitted, ive done about 1500 miles since about 14 months due to it being off the road at the dealers (grantham volvo) the box still takes time to engage drive then slams into gear! putting god knows what kinda strain on the other components!
i find it sad to say but im at the end of it all now so i have two options..drive to grantham and stick it through there showroom window or part exchange it for another make..NON volvo
sad really as it has been a great car, but volvo just wash there hands of it after taking the money for the bodged repairs
if you have the same problem then from my experience then just cut your loses and get rid of it ASAP
and steer clear of grantham volvo they really dont know what they are doing!!

Is there a full proof way of testing whether it still has the stop/neutral function still?

Flushed and changed the transmission fluid through today with some Vauxhall fluid, only problem is I've gone to check the level and it's well over the level it was before on the dipstick. Am I supposed to drive the car to get the fluid circulated thereby removing any air that has been introduced by the flush.

Best to check the level after a run of around 20 mins, gear lever in park and engine running.

However if it's well over the top I'd suck/drain some out before driving it far.