2002 S60 AWD AW 55-50SN Solenoid refurb-it worked

Post by **precopster** » 06 Jan 2014, 16:22

I had some success last week with repairing the solenoids on the AW 55-50SN gearbox as fitted to the 2002 AWD S60.

To say it was a nerve racking experience is an understatement. TOTAL concentration is required and no interruptions while working if this isn't your forte and you're a first timer. The car was at my MILs and she was away at the time so I had uninterrupted time on the project.

Dropping the subframe wasn't that difficult. I used the procedure from the repair database on Matthews. Hardest part was refitting one bolt for the trans line and dipstick which would have been a cinch if I'd removed the clamp on the hose going to the intercooler from the throttle body.

Also I didn't release the lower radiator hose & drain the coolant as I didn't bring anything to catch the coolant with and managed enough clearance to remove the valve body cover quite easily.

Another snag was that I couldn't undo the large (24mm I believe) nut on the trans cooler line on the cover so I simply left it attached and this presented no problems.

Also removing the endcaps was challenging until I ground off a 6mm section to help lift the old cap off.
A Dremmel tool would be ideal for this.

I checked all the solenoid's tolerances as per the included instructions which were very comprehensive and detailed. I went with the reamer kit and gasket set as sold by eBay seller ctppowertrain. Matching valve body gaskets to the body was difficult and requires a lot of concentration as the kit arrives with all possible gaskets included.

All in all a very worthwhile job; transmission finally behaves and the flares and banging downshifts are gone.

Post by **vtl** » 07 Jan 2014, 10:49

Very nice! Planning to do the same on 2002 V70 next spring.

Post by **precopster** » 07 Jan 2014, 14:57

The other bonus is that manual shifting using the Geartronic is now a pleasure to use, though I find it diificult to adapt to the up/down design instead of the regular H pattern.

Post by **oragex** » 07 Jan 2014, 15:56

Holly batman, now that's a diy job, congrats

Post by **precopster** » 24 Jan 2014, 04:23

To make the procedure a little more understandable I thought I'd throw up the Transgo install guide which without would have been a needle in a haystack.

dialex · Post by **dialex** » 29 Mar 2014, 10:15

Thank you for the detailed post!

Post by **jimmy57** » 29 Mar 2014, 13:59

Electronically controlled transmissions have reduced wear in the friction parts significantly but now the solenoids are problematic. I would imagine the solenoid weaknesses will be addressed soon if it hasn't already been fixed on any new units introduced.

Post by **oragex** » 29 Mar 2014, 16:16

The solenoids work well. It's was the transmission manufacturer (Aisin) managements that had a problem:) Because they choose to suggest no fluid replacement for the life of the vehicle, the metallic particles produced by the clutch disks wear, kept stay in the fluid and ultimately got stuck on the rod inside the solenoids. As a consequence, the solenoid won't move freely on the rod and the problems start. A fluid change about every 30k miles will prevent this to happen. On top of it Aisin designed these transmissions with a non serviceable internal filter that we might guess is less efficient at high miles. Basically these transmissions were very robust if the fluid was serviced - which nobody did because Volvo/Aisin decided not to suggest. I might be wrong, but I think Volvo image took a solid hit because of this issue (and also because because they sold their car division to Ford in 1999).

Post by **precopster** » 30 Mar 2014, 01:50

Aisin supply the AW55-50SN to GM, Saab & Nissan as well as Volvo. The same fluid change advice was given to all of these companies. Just look up AW55-50SN on GM (Saturn), Saab or Nissan (Maxima) forums.

There is a company in USA called Omega Machine. Higher quality bushings can be purchased for $5 x 2 per solenoid making it a $30 per vehicle cost. Unfortunately reaching the bushings involves removing the crimps on the casing costing an extra $300 in tooling for crimp removal tools (also from Omega)

The bushings used in the solenoids were made of a poor material which attracted particles in early builds and were subsequently improved in 2003.

This is primarily why statistically 2003 plus cars have a far lower transmission failure incidence even with the same lack of fluid change advice.

Post by **xHeart** » 30 Mar 2014, 06:42

precopster wrote:...
There is a company in USA called Omega Machine. Higher quality bushings can be purchased for $5 x 2 per solenoid making it a $30 per vehicle cost. Unfortunately reaching the bushings involves removing the crimps on the casing costing an extra $300 in tooling for crimp removal tools (also from Omega)

The bushings used in the solenoids were made of a poor material which attracted particles in early builds and were subsequently improved in 2003.
...

Awesome find Mike... more to support and explore https://www.omegamachine.com/db/AW55-50SN%20Solenoid%20Opening%20Tool.asp.