Heavy Steering

[pierremcalpine]

Hi gang,
The power steering on my '04 S60 2.5T is pretty heavy. As part of the safety inspection that the car was subject to for registration I was told I had to replace my steering lower u-joint (which I did). The steering wheel now feels smoother and returns to centre more easily.

However, it is still overly heaving.

I'm wondering if any of you have had to replace either the rack or the pump and what your symptoms were prior to replacement. I have zero noise or grinding, just seriously heavy steering particularly at low speeds. I'm inclined to change out the pump next to see if that makes a difference but am interested to hear of others' experiences.

Any comments are welcome.

Of note, the previous owner (who wasn't very inclined to address any issues beyond oil changes) noted a power steering issue when he sold to car to me. I took one look at the (clearly leaking) reservoir and determined that it needed a replacement. No leaks now but I do wonder how long he operated it with the leak and whether it could have permanently damaged the pump but running it low on fluid for extended periods.

[cheshired5]

Is the fluid clean and green CHF11s?
What size tyres do you have and what pressure are you running?

[Dancake]

I thought CHF11S was used in pre-2001 Volvos, and anything from 2001 onwards used CHF202. Pentosin are the OEM for the fluid regardless. Tyres can have an effect on the felt weight of the steering, even if they have a few mm of tread left. The type/design of tyre can also have an effect, with the surface area of rubber contacting the road varying with tread pattern.

[oragex]

CHF11S and CHF202 are almost the same, CHF202 is a slight improvement but really just by very little.

Most eurpean car dealers have these fluids (VW may be cheaper)

[marcb]

I would suspect the pump too as it a fairly easy thing to replace but if you can afford it try and get a new Volvo OEM one not a refurb.

Steering went very heavy on our 2005 V70 at parking speeds and Volvo indy put on a sequence of three refurb pumps - first two were rubbish although one had a very noisy bearing. The third is OK.

But the steering is fairly heavy anyway on these cars I reckon especially if you have 17 inch wheels with low profile tyres like ours.

[oragex]

One thing I wish someone will do one day, is to put a pressure gauge on the high pressure line after the pump and see how much of the 110 bar is still happening there. That will give a good idea if the pump is worn or not. If the pump is worn, I second that refurbished units won't do more unless they come from a low miles car (under 80K miles) because the bore cannot be refurbished on these pumps.

The S80 has a 120 bar pump and it does this by using a smaller pulley (so the pump rotates faster). Since I think the S80 is using the same serpentine belt, I'm looking at installing this pump on my S60 see how it goes.

Just throwing in there an experience I once had with the steering. As many, my steering is on the heavy side, especially at lower speeds. It also feels numb and 'lifeless' if you want. One day I just lifted the reservoir more upwards from it's bracket and keep it upwards along with the hose to the pump. I drove like this around with the hood unlatched (but not lifted) to make more place for the reservoir. The steering was completely different, like not only like it was another car, but it was just amazing feeling, something I haven't seen on other cars. It was easy to steer and had at same times a lightness and an 'weight' to it. The balance between the two was just amazing, something perfectly calculated, not just a subjective impression. I wonder if on a Bentley if feels like that.

So maybe that is the real steering feeling of a new P2.

Why it doesn't always feel like this? Is it the pump? It is the rotary valve inside the rack that goes clogged ? Who knows..

[pierremcalpine]

Thank you guys. I’ve got nice clean new CH11 in there and it’s good and green. We have 17” wheels in with whatever tires are called for can’t recall size. I think all four tires are at 35psi but I will double check. Thank you for the feedback on the refurb pumps. I will stay clear of those. I did see a Bosch pump on the FCP Euro site for a reasonable price. Any experience with those? They are half the price of the Volvo branded units.

[oragex]

ZF makes them. The manufacturing date is shown on the sticker

Cheaper ones are 'refurbished' (ie sand cleaned with a new seals at the pulley and cover)
a 120 bar for S80 https://www.fcpeuro.com/products/vol...90-oem-8251738

New 110 bar for S60 https://www.fcpeuro.com/products/vol...0-xc70-8251957

[ASt85]

Originally Posted by pierremcalpine

Thank you guys. I’ve got nice clean new CH11 in there and it’s good and green. We have 17” wheels in with whatever tires are called for can’t recall size. I think all four tires are at 35psi but I will double check.

Just a thought, is the "brass" restrictor tube in place in the reservoir inlet pipe, it should be visible in the inlet if you take the inlet rubber pipe off. If it isn't there, it will have ended up in the bottom of the reservoir as the inlet tube expands with age, or may have been expelled when you flushed the system. If it isn't in place the system cannot develop the correct pressure which causes the system to "go heavy" as well as making the fluid "frothy".

It is also worth checking the seal on the reservoir cap and whether the reservoir is leaking around the seam.

[pierremcalpine]

Originally Posted by ASt85

Just a thought, is the "brass" restrictor tube in place in the reservoir inlet pipe, it should be visible in the inlet if you take the inlet rubber pipe off. If it isn't there, it will have ended up in the bottom of the reservoir as the inlet tube expands with age, or may have been expelled when you flushed the system. If it isn't in place the system cannot develop the correct pressure which causes the system to "go heavy" as well as making the fluid "frothy".

It is also worth checking the seal on the reservoir cap and whether the reservoir is leaking around the seam.

Hmmm, good question. Is the tube itself part of the reservoir assembly? If so I’m thinking the tube is in place as I just replaced the reservoir with a genuine Volvo one last month. Would that make sense?