Steering: V40, 2000, 2.0L, cause of memory steer?

[berg07]

A v40, model year 2000, 2.0 litre, 260 000 km, pulls to the right after right turns. After a turn to the left it goes straight again. The car has a kind of "memory steer" but only to the right. If I stop the car and turn the steering wheel all to the left and then back to the middle, the car stops pulling to the right.

No brakes appear to be on, the tire pressure is the same in all tires, the tires are under a year old. The car had a wheel alignment last week, but still pulls to the right. Once it starts pulling to the right, it pulls even while temporarily driving in the left lane where the road leans more to the left (I live in a country with right-hand traffic).

What are the possible causes for this kind of memory steer?

I have owned the car for about two months and unfortunately do not know much about its history. However, it has coilovers and the upper strut mount on the right side has a slight play. When I turn the steering wheel when the car is stationary, the springs ”twitch” on both the right and the left coilover, slightly more at the right front wheel than on the left. Kind of similarily as the springs in this video https://youtu.be/khZ16AOztT4

Can a bad strut mount bearing cause the car to pull to the right?

In Haynes’ manual, it is stated that the installation of the front strut differs depending on whether the car has Sport or Dynamic chassis. I do not know what type of chassis it has.

At https://www.volvoforums.org.uk/attac...7&d=1396056894 it says that it is possible to find out the chassis type from the VIN-plate in the engine compartment.

However, on my plate there is nothing at all where the six characters long code should be (eg., 2BV1BX). How do I know which chassis type I have?

[clarkey1984]

The sound is coil bind, every car I've ever had with coilovers fitted has made that sound, and while I can't be certain a bad top mount will cause your specific issue, one with excessive movement will make it handle bad, my old one which was really low used to eat top mounts and always handled weird when they needed changing.

[V40T4R]

What Clarkey said... take the strutts off and you might find "the memory"

[clarkey1984]

Mine was worse than the example you posted, mine was more like this, although it improved greatly once I changed the top mounts and bearings and slathered the spring and bearing in grease, oh and also wound the ride height up by about 15mm or so, not altogether sure which one of those things was the definitive cure but it near enough disappeared after that.

+ YouTube Video

[berg07]

The problem disappeared after replacing the right strut mount bearing (OE-part number 30616825) and the strut mount (part number 30652259).

The bearing was finished and had trouble spinning. The strut mount looked ok, but seemed have some play in it when the weight of the car put stress on it, so I replaced it. I also switched the same parts on the left side. The left side bearing was not in equally bad shape, but it was only a matter of time before it would break.

The previous owner had installed FK coilovers SMVO9001. However, the bearing that was installed (OE part no. 30616825) was newer than the car since it was introduced in May 2000 (my car is registered in October 1999 but is listed as a 2000 year model, therefore it should have the bearing with part number 30875399 as original). The previous owner has probably modified the strut mount to make these coilovers fit.

Replacing the strut mount bearing was easier than I thought because the coilover did not require a spring tensioner to be dismantled, the springs did not put pressure on the mount. I unscrewed the piston nut and replaced the bearing and the strut mount.