V70 2001 Power Steering Reservoir leak and PS fluid question

skaupert · Post by **skaupert** » 28 Mar 2009, 19:23

2001 V70 non-turbo, US, mfr. 01/01, 96K miles, no mods, runs great.

About a week ago, I discovered a slow leak at the bottom/supply hose connection of the Power Steering reservoir. Topped off the fluid with Dexron III, as per User's Manual and Haynes Manual (british).

Then did some research about the leak, and found that this seems to be a common problem.

I also found (thanks, Howard - http://freewebs.com/howardsvolvos ) that the manual is wrong about ATF, and that the correct fluid is CHF 11S. To make matters worse, ATF seems to pose a problem to both the pump as well as the rack seals, leading to leaks and a noisy pump.

I have four questions:

1. Does anyone know where this leak typically occurs (hose, reservoir, connection, clamp), and is this a repair that requires replacement of reservoir/hose/clamps? (I ask because once I take it out to examine, I seem to have to cut the clamps and/or hoses and am committed to go through with the repair, whatever that entails)

2. Does adding about 4oz of Dexron III pose an actual risk of leaks, or worse, is there an incompatibility between CHF 11S and ATF, such that it is advisable to drain the system and refill with CHF 11S (somewhat expensive at around $25 per liter).

3. And what's the total volume of PS fluid needed (manual is mum on the subject)

4. Is there a Service Bulletin on the leaking reservoir?

slc10844 · Post by **slc10844** » 29 Mar 2009, 08:07

I am in the same boat as you are. I replaced the hose clamp with a worm drive clamp. It held for awhile but it required additional tightening after a couple of weeks. I'm thinking of putting a spring clamp on instead. I too used ATF but ended up going to the dealer and purchasing the Volvo recommended fluid. I sucked the fluid from the reservoir and filled it with Volvo PS fluid. I will probably do this a couple more times, which will require a second bottle of fluid. You might want to check with the dealer about a replacement clamp.

skaupert · Post by **skaupert** » 29 Mar 2009, 08:11

Making some progress:

The two tech notes I found so far regarding the leak:

TNN64-10-08142001

TNN64-17-2007-08-24

I assume that readers of this forum know where to find and purchase tech notes. If not: https://www.volvotechinfo.com

What I glean from those is that the failure comes from the single-use clamp. The TNN instructs volvo service to replace the clamp *and* the hose. But I'm not convinced that's necessary. BTW, the hose is $70 and up, including a more recent version that's around $180. I'm going to start by replacing the clamp with a screw type. Probably on both the supply and return hose. So that answers questions 1 & 4, mostly, although I wouldn't mind hearing from someone who's dealt with this issue.

I'll report on my process and outcome.

However, that still leaves me looking for a definitive answer on the power steering fluid. Anyone?

Thank you!

skaupert · Post by **skaupert** » 29 Mar 2009, 08:21

Thank you, slc10844:

this is very helpful. I'll try to get OEM hose clamps, and I will also examine the inside of the hose where it's attached to the tube at the bottom of the reservoir.

I already have one can of CHF 11S, and am also considering getting a second one to (ideally) replace the fluid completely.

It seems that no matter what I'll do, I will only be able to lower the concentration of the ATF. The question is, how much. Unfortunately, I didn't find a TNN on what to do when a customer comes in with 'mixed' power steering fluid, which must occur quite a bit.

Post by **MadeInJapan** » 29 Mar 2009, 08:55

On the P2 cars I would only use the Volvo PS fluid- I just don't know enough about what they are using to take my chances with ATF which is what I use on the older model Volvo's (all of my other Volvo's) with good results. Someone said on the P2's it's the same as Pentosin (spelling?) but I'm not sure and don't have validation.

skaupert · Post by **skaupert** » 29 Mar 2009, 11:48

Thanks, MiJ!

I think it's pretty much understood that the Pentosin CHF 11S is the correct fluid.

The question at this point is the significance of about 4 oz. of ATF well mixed into the power steering circulation.

a. can I forget about it?

b. should I lower the concentration by extracting what's in the reservoir and replacing it with the proper fluid (which I have on hand)?*

c. should I panic, and do a complete replacement of the power steering fluid, before I move the car another inch?

Surprisingly *no one* seems to know the answer, just a lot of erring on the side of caution. I've scoured the various sites and forums pretty well, including the tech note library, and there seems to be nothing definitive out there.

*some math here: if the reservoir represents about 25% of the total volume (educated guess), then option b would reduce the concentration to about 3 oz of ATF (Dexron III). Repeating the process would get it to 2.3 oz, etc. IOW, until I do this 4 or 5 times, I won't achieve a significant reduction of the ATF. And at no point would it be completely eliminated.

slc10844 · Post by **slc10844** » 29 Mar 2009, 12:05

Ideally a complete flush should be done. I don't know how long the CHF 11S has been recommended, and not sure if it was factory fill in 2002, but since Volvo said ATF could be used in my application I am electing to dilute the ATF as much as possible. I don't anticipate any problems using that approach but if something comes up later I'll deal with it then.

If the dealer replacement clamp is the same as what is on the hose you may want to try something else.