(EDIT, EDIT, EDIT
: Since you have oversteer the alignment should be more Zero and you can inflate both front and back to 47 of the 51 max Cold PSI. You can try 47 front and 44 PSI Cold in the back as a stiffer front will produce an understeer. Everything else below is still applicable for normal to understeer conditions. The alignment and tire pressure is to compensate for the design and incompatibility of the Contis.)
09 S60 2.5T AWD currently under 120K miles was in newish condition till the right side got T-Boned from a Jeep speeding back out of a parking space. Still on the road however. So the rest of the fleet was and is a 00 S70 SE, 02 V70 XC, 03 S80 T6, 08 C30 T5 and 12 XC90. I have been doing my own alignments for over 25 years and do play around with suspension upgrades. In reading all the above I would say it’s just those Contis. Didn’t list these as they aren’t Volvos. Had 20″ Contis DWS on a new 19 VW Atlas VR6 4Motion and on the current 05 Lexus GS430. Would never buy them again. The sidewalls are too hard and square so not good for cornering. Also lacks center feel as the tire has a flater contact path (flat top) compare with other tires in the fleet.
The S60 wheel base is very short and track and wide so an AWD will have a large scrub radius when turning so the front wheels will bind more than normal when turning. I noticed I didn’t like the feel of the 09 S60 AWD compared with all the other cars and the 02 V70 XC and 12 XC90 both AWD. The turbo is out on the 07 S60 2.5T with 235/45/17 tires. I noticed the extreme scrubbing of the tires when I push it out of the garage to reposition it. It did not start so had used the 02 V70 XC to push while turning the wheels and let me tell the front tires complained. This experience was a week ago.
Cross rotate the front and if it doesn’t change new tires are in order or live with it. You might however be able to minimize the affect? Volvos need to be slightly Toe In in the front and back. If the alignment shows 0 or slight Toe Out though still green on the machine tolerance, you’ll experience that snappy or snap back understeer on a big highway sweeper. This especially on the square and hard sidewalls of the Conti. Instead of flattening progressively on the edge of the tire the Contis hard side walls are kicking back. You’ll also get bump steer hitting the expansion joints from one portion of the freeway to the next section on those sweepers. The faster you go to more hairy it gets! Almost lost the Lexus on a round about at an intersection one time. The car has front strut and rear shock tower braces besides a larger rear sway bar. All struts and shock are also new. The stiffness of the tires during the turn in and turn out so quickly at the round about upset the tires then car as it couldn’t keep up with the fast transition that it felt like I was going to flip it as it jerked left then right.
Check the Toe with a measuring tape. Helps with 2 persons. Video for ease of reference but do not use the sidewall but hook the tape measure to the same rib at the same height front and back of the tire to determine amount of toe. I usually set for no more than 1/8 of inch toe in compared with back.
Saw this years ago on our 83 GTI which my Dad allowed me to purchase for the family as he knew I liked car. The shop that everyone went use a flat bar with sliding pointers instead of a rack. I was shocked on how easy it was and found most FWD only has a toe adjustment. Was use to the family mechanic with an alignment rack back then.
How to Measure Toe-in of Wheel Alignment
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I did perform a 4 wheel alignment using for jack stands on the 09 S60 as it had a bent rear toe arm when it was purchased in Dec 2023.
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