Master O-Ring & Part Replacement List
SAAB 9-2X AERO (2005, 2006)
SUBARU IMPREZA WRX (2004, 2005, 2006, 2007)
SUBARU IMPREZA WRX LIMITED (2006, 2007)
SUBARU IMPREZA WRX STI (2004, 2005, 2006)
SUBARU IMPREZA WRX STI LIMITED 2007
SUBARU IMPREZA WRX TR (2006, 2007)
To completely rebuild this guy you'll need the following:
1 - AS568A Dash Number 136 O-Ring
1 - AS568A Dash Number 119 (or maybe -021) O-Ring (Although myself and a select few others got the -021 ring to seal many other's did not. I can no longer, in good conscience, recommend the -021 ring. Just get the 119 it's 1/32 inch [~0.8 mm] thicker having the same I.D. as the -021 and seems to work in every pump.)
1 - AS568A Dash Number 037 O-Ring
1 - AS568A Dash Number 017 O-Ring (behind the 10mm allen 'hex plug')
1 - AS568A Dash Number 015 O-Ring
- AS568A Dash Number 014 O-Rings (that's three total for full replacement)
1 - AS568A Dash Number 013 O-Ring (Some have suggested to only get a Buna-N ring for the 013. This is the one that seals the sensor to the back of the pump. It is difficult to install if you get the FEP, but not impossible. Read Mike-easy's assessment here.
Buna-N if you want to be safe, with less hassle.)
1 - Bearing 17mm I.D. x 40mm O.D. and 12mm width. Prices range from $6 to $106 from McMaster.
1 - Oil Bearing Shaft Seal 20mm I.D. x 32mm O.D. and <= 9.3mm in width. "<=" means less than or equal to
O-ring materials known TO WORK rebuilding this powersteering pump:
Buna-N - Used in all OEM pumps. Inexpensive and will last as long as OEM ones.
FEP Encapsulated - Upgraded materials with upgraded prices. Better than Buna-N
O-ring materials known NOT TO WORK rebuilding this powersteering pump:
PTFE - Too hard as tested by Othon
Viton® Fluoroelastomer - Tested by Othon
Regarding the Seal: I found one at RocketSeals.com P/N 20X32X8-MOS/D
which looks like it would excel as a replacement. The I.D and O.D. need to be exact. The width just needs to be <=9.3mm. RocketSeals P/N 20X32X8-MOS/D has been tested and found to fit perfectly by our very own othon
. Thanks guy. Also a report of Carquest seal PN# SLS 222020 OR INTERCHANGE # AE0997E0 WORKS GREAT
for the shaft seal.
BeratE put together a list of the Part Numbers for the FEP encapsluated O-rings and a great bearing from McMaster in this post
2013-Feb-17: Reliability update on FEP Encapsulated. No issues on my PS Pump. No leaks. No pulsing. No ATF consumption. Works without problems.
2013-Apr-13: Reliability update on FEP Encapsulated. Still running strong. -021 O-Ring doing fine on my rebuild. A few reports of it being too thin for some pumps. -119 is next thickest size, if that applys to your pump.
2013-Nov-15: Reliability update on FEP Encapsulated. No issues. No leaks.
2014-Mar-12: Now recommending the -119 ring over the -021. Too many people have had issues with the -021.
2015-Sept-05: Reliability update on FEP Encapsulated. No issues. No leaks.