When should you change PAS fluid?

Just your normal general chatting in here..

Moderator: Moderators

Post Reply
Welly
The moderator formally known as Welton
Posts: 14893
Joined: Tue Jan 10, 2006 12:52 pm
Location: East Midlandfordshire

When should you change PAS fluid?

Post by Welly »

My car is nearing 10 years old and I know the PAS fluid is the original from the factory (probably the only thing left that is :roll: ), thing is I've never changed the PAS fluid on any of my cars :?

What do you lot do? leave it alone? change it every few years? inspect it? send it to a Laboratory for analysis? :)
Cars in my care:

2005 Volvo S40 T5 German Diesel botherer with new tyre grippage
2010 Citroen C4 1.6 HDi turbo de' explosions, bizarre gearbox model
2010 Renner Twingo refreshingly simple

markw
2.0 Turbo
Posts: 401
Joined: Tue Jun 11, 2013 2:27 pm
Location: Suffolk, UK

Re: When should you change PAS fluid?

Post by markw »

As there's no 'official' drain point provided, I guess they expect it to last the life of the car. :shock:

I had to replace mine simply because the servo valve on the rack died and to replace it, all the fluid escapes....
2001 ES9J4S Coupe Manual Diablo

Rolebama
2.0 Turbo
Posts: 316
Joined: Wed Dec 04, 2013 2:15 pm
Location: Middlesex (NW London)

Re: When should you change PAS fluid?

Post by Rolebama »

I have never changed PAS fluid. After all, it isn't subjected to particularly high pressures. The only checks I know of (apart from level checks), is to get a drop on a piece of kitchen roll and after it has soaked in, check the colour and for any particles. (Which usually indicate component wear). You can rub it between finger and thumb to check for particles, but I don't feel it is 'exact' enough, as I used to have callouses.
Working in garages, FWIW, I have replaced it through component replacement way before I would replace it because it has 'worn out'.
1998 2.1 GLX TD

Welly
The moderator formally known as Welton
Posts: 14893
Joined: Tue Jan 10, 2006 12:52 pm
Location: East Midlandfordshire

Re: When should you change PAS fluid?

Post by Welly »

Hmmm, interesting, thanks.
Cars in my care:

2005 Volvo S40 T5 German Diesel botherer with new tyre grippage
2010 Citroen C4 1.6 HDi turbo de' explosions, bizarre gearbox model
2010 Renner Twingo refreshingly simple

markw
2.0 Turbo
Posts: 401
Joined: Tue Jun 11, 2013 2:27 pm
Location: Suffolk, UK

Re: When should you change PAS fluid?

Post by markw »

In a pdf I have which details how to test the pressure in the system, it states that at 1500 rpm, the pump should be capable of providing 100 bar, + or - 5 bar.
I'd say that was quite high. :wink:
2001 ES9J4S Coupe Manual Diablo

Welly
The moderator formally known as Welton
Posts: 14893
Joined: Tue Jan 10, 2006 12:52 pm
Location: East Midlandfordshire

Re: When should you change PAS fluid?

Post by Welly »

I mustard mitt I always understood there was a high and a low pressure side to the system.

Mine has an electric PAS pump (Volvo) and the current it draws is enough to pull down the National Grid, that's what got me thinking about the fluids' quality/lifespan.

Is this the right time to admit to never opening the PAS reservoir cap in nearly 6 years? :supafrisk: in my defense I can see the fluid through the clear(ish) reservoir I just haven't 'inspected' it.

Think I'll get it changed along with the gearbox oil as that's due now too.
Cars in my care:

2005 Volvo S40 T5 German Diesel botherer with new tyre grippage
2010 Citroen C4 1.6 HDi turbo de' explosions, bizarre gearbox model
2010 Renner Twingo refreshingly simple

steve_earwig
Moderator
Posts: 19385
Joined: Thu Oct 04, 2007 6:09 pm
Location: Jastrebarsko, Croatia http://www.jastrebarsko.hr/lokacija/

Re: When should you change PAS fluid?

Post by steve_earwig »

I've absolutely no idea if it's necessary but I guess it'll give you peace (piece?) of mind if you change it. Unless it costs you a kidney.
Unskilled meddling sin©e 2007

2004 D9 2.0 HDi 110 Estate lhd VF38ERHZF81657352 - sold but being very well looked after.
1991 Yamaha TDM850 - fuel leaks galore!
2008 Toyota Recall4 2.0 VVTI ATM LHD JTMBH31V90D007261 - flimsy piece of crap.
1953 Matchless G3LS - It's alive!!

Bailes1992
Moderator
Posts: 4264
Joined: Mon Dec 24, 2007 4:13 pm
Location: Bridgend, South Wales

Re: When should you change PAS fluid?

Post by Bailes1992 »

The MK4 Mondeo suffers with PAS failure.
The seals in rack degrade and block up a filter in the reservoir. This starves the pump and the rack and causes them to fail.
When I got the car I changed the PAS fluid and reservoir. The filter wasn't replaceable.
I removed all the pipework and blew through all the pipes with an airline. I dripped fluid into the pump and spun it by hand to flush it out.
I then dribbled fluid into rack and got my other half to turn the steering from lock to lock to flush the rack out.
I put it all back together and filled the system back up.
The new reservoir has a removable filter so once a year I drain the reservoir, clean the filter and fill the reservoir with fresh fluid.

So far I've had no issues with my PAS.
2019 Volvo V40 D3 Geartronic R-Design Edition My Daily
1996 Land Rover Defender 90 County SW 300TDi My Toy
2003 Ford Mondeo ST220 3.0 V6 My Other Toy
2018 Jeep Renegade Longitude eTorq 2WD My Wifes

Welly
The moderator formally known as Welton
Posts: 14893
Joined: Tue Jan 10, 2006 12:52 pm
Location: East Midlandfordshire

Re: When should you change PAS fluid?

Post by Welly »

I've heard of that on the Fords, I was kinda wondering if my Volford has the same unit.........place yer bets!
Cars in my care:

2005 Volvo S40 T5 German Diesel botherer with new tyre grippage
2010 Citroen C4 1.6 HDi turbo de' explosions, bizarre gearbox model
2010 Renner Twingo refreshingly simple

Rolebama
2.0 Turbo
Posts: 316
Joined: Wed Dec 04, 2013 2:15 pm
Location: Middlesex (NW London)

Re: When should you change PAS fluid?

Post by Rolebama »

The ability to work at 100bar is a bit of a misleading comment as the system rarely works that hard. Maybe if you tried to turn the steering with both wheels stuck somehow you would generate that pressure, but probably don't even come close in day-to-day usage.
1998 2.1 GLX TD

Bailes1992
Moderator
Posts: 4264
Joined: Mon Dec 24, 2007 4:13 pm
Location: Bridgend, South Wales

Re: When should you change PAS fluid?

Post by Bailes1992 »

Welly wrote:I've heard of that on the Fords, I was kinda wondering if my Volford has the same unit.........place yer bets!
I've never heard of the issue with Focuses to be fair. I know the Volvo S60, V60 and V70 suffer from it, as do the MK4 Mondeo, S-Max and the Galaxy.
2019 Volvo V40 D3 Geartronic R-Design Edition My Daily
1996 Land Rover Defender 90 County SW 300TDi My Toy
2003 Ford Mondeo ST220 3.0 V6 My Other Toy
2018 Jeep Renegade Longitude eTorq 2WD My Wifes

Welly
The moderator formally known as Welton
Posts: 14893
Joined: Tue Jan 10, 2006 12:52 pm
Location: East Midlandfordshire

Re: When should you change PAS fluid?

Post by Welly »

Oh yeah I forgot mines a Focus, might be ok then :)
Cars in my care:

2005 Volvo S40 T5 German Diesel botherer with new tyre grippage
2010 Citroen C4 1.6 HDi turbo de' explosions, bizarre gearbox model
2010 Renner Twingo refreshingly simple

Bailes1992
Moderator
Posts: 4264
Joined: Mon Dec 24, 2007 4:13 pm
Location: Bridgend, South Wales

Re: When should you change PAS fluid?

Post by Bailes1992 »

Many of the guys on the talkford forum just buy 5 litres of fluid and once a day after a drive they drain and refill the reservoir until they've used all 5 litres.
2019 Volvo V40 D3 Geartronic R-Design Edition My Daily
1996 Land Rover Defender 90 County SW 300TDi My Toy
2003 Ford Mondeo ST220 3.0 V6 My Other Toy
2018 Jeep Renegade Longitude eTorq 2WD My Wifes

Post Reply