So, I have a 1990 240, which I have had for the past 6 years (purchased it from the original owner, at 147k). It had some ECU & CPS issues late winter, so I parked it and bought a 1998 V70 AWD to use as my daily driver.

So, the car sat for maybe 2 months, without moving (I would go start it and let it idle for 30 min once a week), and a couple weeks ago I decided to take it for a spin. It drove great (older issues are nonexistent now), except for the power steering was whining when turning. I checked it, and the fluid was low, so I added some synthetic power steering fluid that I use for my V70. Whining went away, but now the steering wheel shakes during low-speed tight turns.

Did I use the wrong power steering fluid? Or is this another issue? If I used the wrong kind, I'm going to flush and clean the system, and add in the correct kind.

Haven't driven the car since the issue started.

 

Not a good idea to mix fluids like that but I don't think that alone is causing the shake. Still, I'd flush it, put the right Type F in it and see what happens. Also, make sure the P/S belt is tight...

 

I don't think they are fussy, I've used ATF in them before without any problems.

check the PS belt. also check the tires, and the front end joints (tie rod, ball joints, strut mounts, lower control arm pivots).

 

ATF, right, type F, is what you are supposed to use...

 

well, I used dex/merc III, Castrol Import MultiVehicle, same as I put in my tranny.

 

You may have air bubbles in the rack. Whenever I have had my power steering apart I get that shuddering at low speed turns as the air bubbles work their way out. Instructions (when installing a rack) state you should turn the rack lock to lock several times prior to starting the engine and that should get the bubbles out. Even when I did that it still shuddered. The shuddering went away after a few days.

 

What act1292 said. If you keep the fluid topped up, the "lumpiness" and noise will eventually go away in normal driving, but it's quicker to jack up the front or have the wheels on something slippery and crank the steering lock-to-lock with the engine running to purge the bubbles.

As for fluid, Volvo specifies Type 'F' ATF for my 740, but I've found no specific reason why. From what I know, Type F has slightly different friction properties than Dexron and people have used it in their Dexron auto transmissions to get more positive shifts. I've used Type F when I've had it and Dexron other times and found no difference.

 

I suggest that you start with FRESH fluid.

my 400k steering system is complaining too. It was getting stiff at light loads on the freeway and jerky when parking. I simply disconnected the PS reservoir, and dumped the dirty old fluid in a bucket CAREFULLY. Then put fresh fluid in and it has helped a lot. It's starting to come back sometimes, but it works well enough for now.

It really doesn't matter what fluid you put in there. I just run any old PS fluid from the parts store.

 

after getting air in to the PS system, you run the engine and turn stop to stop back and forth a few times slowly (ideally with the wheels in the air to minimize stress on the bearings and tires), refilling the PS reservoir as the level drops..

 

Just driving it you should have already been lock-to-lock many times and blown any bubbles out, but it's a good idea to do that procedure anyways right when you put new fluid in so you or the customer don't get any surprises. Kinda like new brake pads and hitting the brake for the first time.

 

I have performed the bleeding process as well and I really can't say it did much good. It seems to me that when you start the engine the first time, the ATF in it foams forming tiny bubbles. Turning lock to lock doesn't really get all the tiny bubbles out. It takes a few days for them to all coalesce and work their way out.

Yeah - this should all be done with fresh fluid.

 

I worked at a place where their $95 power steering "flush" consisted of a tech pulling the fluid out of the reservoir with a turkey baster and then refilling. I don't work there anymore.

 

I've done a half-arsed 'change'/'flush' by sucking out the old fluid, replacing it, turning back to back slowly several times then repeating (such, replenish, turn). after about 3-4 of these passes, the stuff I was sucking out was pretty clean. Didn't get any foam because I didn't let any air get into the system.

 

Also check to make sure steering shaft isn't hitting anything. I have seen it happen. wont exactly cause symptoms listed, but can cause you to feel it in the steering.

My half assed flush was good enough to get the stiff spot out of the steering for tens of thousands of miles. It shows up here or there, but now it feels like more of a slipping belt. It showed up recently after i got the belt wet spraying water around during another test.

 

Thanks a ton for all the input on this. I jacked the front end of the car, drained the PS system. Filled it with cheap ATF fluid, went lock to lock, and then drained the fluid again. Repeated 3 times total, fluid draining at the end was pretty clean looking. Then I topped it off with the nice ATF fluid, went lock to lock until the level dropped, then topped it off again. No wobbles in the steering wheel now!

Still not sure if the wobble was due to the 2 different fluids, or air being introduced when I added the other fluid. Considering how dirty the old fluid was, I'll bet it wasn't mixing with the new fluid, which could have lead to uneven pressurization of the system.

 

Glad you got it. Thanks for posting back.

Your steering rack and pump thank you for your efforts.