850 Front axle alignment issue Topic is solved

Post by **manovlov** » 06 Aug 2021, 09:52

I don't understand it.I just had the redone twice.
The report places the values in the good tolerances recommended by Volvo.

Before that operation, i replaced :
- The steering tie rods
- The end tie rods
- The complete shock absorbers except the springs

The TRW wishbones are 2 years old and since this time the car has covered about 1500 kilometers.

I did not take any shock at the front.
When I accelerate, very quickly the car starts to go to the right.

Does anyone have an idea?

Manov

Manov

Post by **misha** » 06 Aug 2021, 17:02

Uneven tire pressure or bad and old tires...BUT....

If alignment is good and in spec...it can pull to the left or right on hard acceleration if you don't keep your hands on the wheel and keep the wheel straight.
FWD cars don't have equal grip on both front wheels when you floor the gas pedal.

It shouldn't pull to left or right when you cruise at speed and you remove the hands from the wheel.

Of course...it all depends if the road is sloped or flat.
If it is sloped to one side it will pull to one side.

Post by **manovlov** » 06 Aug 2021, 17:16

misha wrote: ↑06 Aug 2021, 17:02 Uneven tire pressure or bad and old tires...BUT....

If alignment is good and in spec...it can pull to the left or right on hard acceleration if you don't keep your hands on the wheel and keep the wheel straight.
FWD cars don't have equal grip on both front wheels when you floor the gas pedal.

It shouldn't pull to left or right when you cruise at speed and you remove the hands from the wheel.

Of course...it all depends if the road is sloped or flat.
If it is sloped to one side it will pull to one side.

Thanks misha. The guy from the shop told me that it was possible that he doesn't know well how to fixe the alignment on that car. I will control the pressure tomorrow. I've decided to go to the Volvo dealer on monday to ask the mind about this issue if the pressure was ok.

I had a paralellism in March, because I had changed just the shocks and nothing else. I compared the values of the two alignments, they are the same. So maybe it's just a question of bad tire inflation, that would seem to make sense. I'll talk about it tomorrow;

Manov

Post by **misha** » 06 Aug 2021, 17:49

You should go to a reputable shop who have the proper alignment equipment.

There is nothing that he should know or don't know...he just need to pick up a proper vehicle from a menu,attach the equipment and to follow the screen.
With proper equipment...anybody can set the alignment on the vehicle.

Equipment can be optical or laser.

Don't bother with visit to a dealer.
They don't know how to fix anything if that is not just part replacement.
They are the same worldwide and they are called "stealership" for a reason.

About alignment....it must be performed ONLY if you replace tie rods.
If you replace shocks,springs,control arms....none of them affects the alignment except tie rods.

Post by **scot850** » 06 Aug 2021, 20:03

Have the rear suspension checked for wear and alignment as well. Were in the rear suspension will cause the front to wander.

Neil.

Post by **foggydogg** » 06 Aug 2021, 21:39

I agree with Neil, there are several rubber bushings in the rear suspension, and sloppiness back there can cause the symptom you describe.
I will not attempt to translate "the tail wagging the dog".

Post by **manovlov** » 06 Aug 2021, 23:56

Thanks Guys ,

Before doing anything, i will follow Neil's advice and start by changing front sub-frame bushes. One step after the other.

I have numbers tracks to follow. I will begin by the tire pressure this morning and control the rear bushing. As far as i can see, there are "only" 2 bushes on the rear, right ?

: Rear bushing.jpg (89.29 KiB) Viewed 882 times

I do remember have seen some pictures on that job done by abscate, if i remember well... But some little searches give :

foggydogg wrote: ↑31 Jul 2021, 19:12 There are rubber bushings back there; Robert Spinner is wrestling with the same issue on his 850 wagon at the moment. If you unweight each wheel in turn - jacked up instead of on ramps - and give a good wiggle with a pry bar on the delta link bushing, you should be able to tell if there is gross movement.

hausmeister wrote: ↑05 Aug 2021, 02:28 If the other 2 bushings go bad (link the pointy part of the deltas, I think "trailing arm end links" is the name) then the rear end kind of drifts around when in a corner or accelerating.

viewtopic.php?f=1&t=97555&p=579692&hili ... on#p579692

Thanks really Guys for your help, you are incredible !

Azik09 · Post by **Azik09** » 07 Aug 2021, 01:22

Try to exchange wheels. Left and right, if they aren't directional, or rear and front. Defective tire can pull the car aside, even if it looks good.

Post by **manovlov** » 07 Aug 2021, 03:28

Azik09 wrote: ↑07 Aug 2021, 01:22 Try to exchange wheels. Left and right, if they aren't directional, or rear and front. Defective tire can pull the car aside, even if it looks good.

Salut Azik09,

Good idea, let's try this first.

Post by **foggydogg** » 07 Aug 2021, 08:55

manovlov wrote: ↑07 Aug 2021, 03:28
Azik09 wrote: ↑07 Aug 2021, 01:22 Try to exchange wheels. Left and right, if they aren't directional, or rear and front. Defective tire can pull the car aside, even if it looks good.
Salut Azik09,

Good idea, let's try this first.

Another good, low-cost trouble shooting step, although I've always been taught to avoid changing radial tires left-to-right.
Front to back is what I've always done.
Keep plugging away at it, you're almost there.