Hi

First, the car:
V70 2.5T AWD 2006

Today, while driving, I started to feel a loss of power steering on some spot on the steering. Let's say I make a left, while turning the steering, I feel a normal steering assistance then it became harder and smoother and harder to turn...

I made a fluid check. While the car in the garage, stationary, engine started, going to a full left to right and then left etc... steering was always smooth. Power steering works fine, fluid is fine. The problem happen only when car is moving.

I know I have an adaptive steering rack (dealer told it to me a while ago) so depending on the speed I'm driving. On the highway, steering is hard while on streets at lower speed steering is always smooth.

I've read that a solenoid on the rack can be the problem sometimes...

Anyone have an idea ? Rack is not leaking.

Thanks for your help !

Some WD-40 has NO lubricant in it - it was designed to disperse water (WD) - a lubricant would cause issues down the road on electrical equipment.

So, now, some WD-40 has lubricant in it - they call it multi-use.

I only use some older WD-40 that I have for cleaning plastic and rubber parts - for light lubrication, I use silicon spray that is safe for plastics - Silicon IS safe for plastic, but some less expensive products use a propellant that is NOT safe for plastics.

We did have to replace the u-joint on one of out 850s and one for our 740s. I could not try to lube them because, in each case, my daughter had the car several states away.

Currently am driving 1996 850 since July 2016. Have noticed recently similar symptons on my car. Will lubricate yoke as K. recommends. Thank You Klaus and TheBrute both!

I had that happen on both my 240 and 850. It was too late for the 240. The lower steering shaft u-joint had to be replaced. With the 850, I was already aware of the issue so when it first happened on my 850 I knew what to do - WD-40. Once, I tried using white "no wash off" lube grease on the u-joint. Didn't work. Cleaned the grease off and went back to WD-40. In my experience, WD-40 works fine. It simply needs to be reapplied when the problem crops up again. Roughly every 2 years or so...

BTW - You might need to this 2 or 3 times. Make sure you go lock-to-lock with the steering for a couple minutes and try and hit the joint from many angles. All of sudden the steering will return to center and they will be no more stiff or dead spots. So don't give up!

The 2006 has a steering wheel position sensor, but I don't think that is your problem.

I would first check the the U joint in the engine bay area. Road salt and high humidity can cause a little corrosion. Try spraying the U joint with an oily product, some of the 850 owners have had success with WD-40 (ugh) and if you use that I would follow that up with something that lasts longer.

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Keeping it running is better than buying new

Hi Klaus,

Thank you for your reply.

I will look into this tonight. Hope it will be that simple to solve.

Nonetheless, like mentioned, when the car is stationary in my garage, I can turn the steerring wheel and never feel the loss of power. Steering is very fluid while not moving the car. It only happens when car is moving...

I'll keep you posted about the fix you suggest,

Bruno