Connecticut has a discount tire chain that we commonly refer to by droping the word Tire and replacing it with Liar. Anyway, they have a deal whereby you can get a front end alignment free with any tire purchase. Except if the car requires a “four wheel thrust alignment” then it’s $49.99. Every car we’ve owned and taken to them requires this, 1993 Subaru Loyale, 2000 Dodge Dakota, 2000 Volvo Wagon, 1993 240 Volvo, 1982 Dodge Van. Is this for real, or is it a bait and switch tactic ?
The guideline I use is if it is AWD or FWD, then get the four wheel thrust alignment. If 2WD rear wheel drive, then a 2 wheel front end alignment suffices.
Some guidance at http://www.familycar.com/alignment.htm. The upshot is: On some cars, rear wheel alignment is not adjustable. On some, it is. Here’s what they said:
Four-Wheel Alignments
There are two main types of 4-wheel alignments. In each case, the technician will place an instrument on all four wheels. In the first type the rear toe and tracking is checked, but all adjustments are made at the front wheels. This is done on vehicles that do not have adjustments on the rear. The second type is a full 4-wheel alignment where the adjustments are first made to true up the rear alignment, then the front is adjusted. A full 4-wheel alignment will cost more than the other type because there is more work involved.
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I am generally happy to occasionally get away with a bill for $49.99. Axle and steering components, including tie rods, ball joints, CV joints, need to be in good condition for proper alignment. But when they finally wear out, replacing them pushes up the cost.
JMHO, but even on vehicles with non-adjustable rear wheels the thrust angle (or track) should be part of the alignment’s regular price. This is adjusted by PROPERLY adjusting the front tie rods as needed to bring the track in as it should be.