Hi All,

Can you give me some insight to when fluid exchanges on our cars should be completed? The passport to service book doesn't go into detail on transmission, differential, or power steering.

I have a 2008 (4.2L Supercharged, 6 speed auto) with low miles (about 5,000) and am wondering what I should look into changing.

Brake Fluid- Every 2 years
Coolant Flush- 5 years or 150k miles
Transmission-?
Differential-?
Power Steering Fluid-?

Thanks for your help!!

 

Diff before 60k or 7 years
Trans before 60k or 7 years
Power Steering 40k or 5 years
Of course, Diff and Trans are "Sealed for Death" so there isn't any OFFICIAL change interval.
Power Steering is whatever it is, as I suck some out with a baster and add fresh about every year.

 

Brake fluid can be dependent on use (heat degradation=reduced efficacy) or moisture content. I have a fluid tester I use for daily drivers that checks for moisture content in the fluid. I have found so in me cars need fluid once per year and some can go four years between changes.

 

Jaguar have gradually reduced the recommended brake fluid change interval over the years from NEVER to the present 2 YEARS. I'm convinced this has more to do with finding something for dealers to do at Scheduled Servicing rather than any particular technical justification. Brake fluids have advanced greatly from the highly deliquescent paint stripper of old to a more stable formulation.

One technique I do adopt to reduce contamination is not simply retracting caliper pistons for a pad change but opening the bleed screws to eject the old fluid which has been in contact with the rubber seals and bleeding through a small volume of fluid until it shows clean. The quality of brake fluid with suspended rubber particles from gradual friction wear on the seals is more of a problem than that of fluid deterioration.

Graham

 

5000 ? Do you ever take it out of your driveway?

 

I've had my brake fluid done last year when I had my discs and pads changed a year ago
Coolant flushed through in April
Just had the diff fluid changed this week at 52.7k (see pic below)
Transmission will be done in the new year
PS Fluid, not sure if this is possible as a DIY?




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supercharged oil needs changing every 50k or 5 years

 

I think physics (chemistry?) of absorbing moisture and corroding inside of calipers remains the same. Long time ago I had an old BMW where PO never changed brake fluid. I did, but it was too late to avoid 4x caliper rebuild.

I haven't read anything about any fluid solving or even substantially mitigating this mode of failure. My impression that newer fluids resist boiling, so you delay onset of brake fade.

 

Since brake fluid is hygroscopic and does absorb moisture over the years, it can be tested for water content with one of the commercially available testers that check the boiling point.

 

See post #3. I have found the Jag reservoir to be really airtight. It usually took about 4 years before I saw any moisture via a tester. Land Rovers and Mercedes also, bit a VW I recently sold would only go about a year before water percentage started to become a concern.

Now that I track the XKR I flush the Motul RBF 660 every 2 years even though it tests free of h2o and brakes still work effectively.

 

Brake fluid is considered 'wet' at just a 3% water concentration and the boiling point is seriously decreased. I'm REALLY liking the new Castrol DOT4! Also, there is a brake fluid tester you can get off eBay for under $5. Buy one for your friend.

 

My Indy replaced my brale fluid when they fitted my Wortec discs late last year. They suspected it had never been changed as water content was at 4.5% on a (then) 4.5yr old XKR. And the price for this work was zero

 

Hi all

I am thinking about replacing power steering fluid on my 2011 after 10 years. I would simply run the engine and steer lock to lock while a buddy will be exchanging the fluid in the reservoir when I pause the engine from time to time. Not a perfect method but easy enough without need to dismantle the reservoir.

questions:

Is changing power steering fluid officially on the maintenance to do list at the Jag dealer? On many cars including my Land Rover Defender there is no official change interval.

the correct liquid is pentosin chf 202, right?

what is the liquid fill volume for the entire power steering system? 1 litre?

br
ter

 

The 5.0 maintenance manual is in the top sticky and has the specs you're searching for.

On my 4.2 the PS flush is done by pumping out the reservoir and connecting the two hoses under the reservoir to extensions. Then, one is placed in the new fluid, and the other in a waste can. Crank the engine & turn the wheel to flow 3 L through and the fluid is almost completely renewed. I used 4.2 spec PS fluid, which is Dex 3. Then reconnect and fill the reservoir to line. Note that because the reservoir filter is part of the unit, some use the opportunity to replace the reservoir. If the Jag reservoir price annoys you, it's identical to the BMW one, for less. For me, it was 15 min setup, 5 min to flush, 15min to button it up. Much more effective than turkey baster. My old fluid at 80K and 14 years was clouded. I imagine the 5.0 process is similar.

 

I do what you stated........ Suck out and replace fluid from the reservoir, lock-to-lock a few times, repeat several times.
That works fine for me, every year or two. I don't see a problem with that method at all.

 

To answer my first question myself:

according to what I read in the sticky section, replacing the power steering fluid is NOT a standard maintenance item. It is only “check/top up”.

br
t

 

yes… and thats precisely the problem. one look at the drained fluid from the power steering rack or the gunk covering the filter in the reservoir will have you thinking about changing it.

 

After three (maybe four?) half-changes, mine's nice and pink and pretty.

 

beware!!! There seem to be confusion in the official documents about the correct power steering fluid!!!

My owner doc says Pentosin chf 202 but the workshop manual specs Dexron 3. Maybe both were used at times. And I am not sure if it is a good idea to mix them.

Dexron 3 is red. Pentosin chf 202 is green. Check the color in your car and I suggest you replace with like. In my case I used red Dexron 3 finally.

br
ter

 

As far as I know, power steering pumps merely create hydraulic pressure. There are no clutches or the like which would have the need for different friction and additive conditions. Would seals care if a different fluid was mixed? Probably not.
As long as any added fluid is non-reactive with the old stuff, does it really matter???