Wheel alignment; castor adjustment 2006 xc70

[Rvolvos]

After replacing the front struts both castor angles are below 4 degrees. Alignment was still okay according to the alignment report.
Before this I replaced the Lower control arms and only the right side was at 3.9 degrees according to the alignment report.
Would trying to move the top of the struts back fix this?

[MoVolvos]

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Instead of correction just make sure the toe (adjustable) and camber (slight play but not made to for adjustment) are within spec and test drive to see if it drives straight.

Almost no average cars these days have castor nor camber adjustments. You can get a concentric bolt for the strut for camber but that was not the factory's intent.

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[Rvolvos]

Thanks for your response. According to the attached alignment report everything is within spec. Except the camber, they recommended a adjustment.

[MoVolvos]

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The car should drive pretty straight but might be a bit squirrely meaning can drift or dart left or right but going right more depending on the crown of the road. This is due to positive toe both front and rear. Everything for all intensive purposes are within spec and Castor is not really a tire wearing angle if you do mostly straight driving even then sorta negligible.

Some cars have rear toe adjustment but you should Zero the front toe or slightly negative but do center the steering wheel while doing so. As for the negative camber rears may not be adjustable. The front with a helper loosen the two steering knuckle strut bolts and pull the top of the tire outward and tighten. Should have a little play and will bring it closer to zero camber and less inner tire wear.

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[Rvolvos]

Sorry I meant caster and not chamber.
The car does wanders a bit and requires quite a bit of steering input to keep straight.
The front wheels don’t have play but are still on the original ball joints and tie-rods. Was hoping if getting the castor within spec would help with keeping the car straight.

[MoVolvos]

Sorry I meant caster and not chamber.
The car does wanders a bit and requires quite a bit of steering input to keep straight.
The front wheels don’t have play but are still on the original ball joints and tie-rods. Was hoping if getting the castor within spec would help with keeping the car straight.

When I read 3.9 in the OP I knew you were referencing Castor. The higher the "Even" Castor right and left the straighter the car will go. The car will pull to the higher Castor side so with yours it is fine as it will slightly compensate for the crown in the road and pull left (minuscule).

Toe is the main spec that determines how straight and stable a car will move straight. Camber pushes the car left or right but if even on both sides it's won't but affect cornering instead and tire wear depending how close it is to zero.

Again, the even Castor will not affect straight line but the Toe for your car. Set the front Toe to zero or slightly Toe In (Positive Toe) to help with going straight besides the wandering and/or darting left or right. When skiing having the ski Toe In helps you go straight. If too much however it will slow you down but in terms of the tire it will wear the outer edges.
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Toe Alignment.png (126.04 KiB) Viewed 3262 times

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Most cars have a slight negative camber in the rear and preferably zero in the front. As mentioned before too much will wear the edge of the tire inner (Negative) while outerwear (Positive). Unbolt the two strut nuts and pull the top of the tire outward (little movement / slop) to bring it closer to zero to help with the wandering and / or darting left and right.

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