At 36,200 miles, I had new tires installed last weekend at costco (Bridgestone Ecopia EP422) on my 2008 Prius. So far very happy with the new tires, although it has been less than a week. Mileage slightly lower but they are new tires. Much quieter than my OEM Goodyear Integrity. So today I went in to my Toyota dealer for the tire alignment. Since I had done some internet "homework", I specified that I wanted a front wheel toe-in of 0.05 degrees each front tire, for a total toe-in of 0.1 degrees. I also asked him to let me know what the rear alignment is (if I understand it correctly, they are fixed and cannot be adjusted). The junior guy looked confused and said I had to talk to the senior guy. The senior guy said they could not adjust the tires as I requested. He said they "just try to get it into the green". When I asked him if the problem was the time it would take, or the actual ability to get it to the exact specs I requested, he said it would definitely take a lot more time, but also that changing the adjustment "would throw something else off". I pointed out that my request was within the manufacturer recommended specifications, but he still said they could not do it. He said they could only promise to "get it into the green". I was not satisfied with this response, and told him I would find someone else who was able to adjust the exact toe-in as requested. Now I am hoping to get input from this forum: Was I asking too much? Or should the Toyota dealer have been able to align the tires exactly as I requested? Also, am I correct that the rear tires cannot be adjusted (without a shim)? Is there a recommended toe-in for the rear tires? Thanks!
It would take little longer to adjust the toe to your specs than just get then in the green but not much longer for a competent shop. I think your "tech" was mindlesly mouthing their policy on free in warranty adjustments without knowing they can do much better work with little extra effort. You were also asking for too much. When you shoot for 0.05 degrees per wheel be aware that just taking the car off the rack and putting it back on can make a difference in measurement that are that big or bigger. A good shop with good equipment could probably set it at close to 0.05 degrees/wheel but as soon as the car is moved it will be off by a bit. Any car will have that problem to some extent, but from what I have seen on alignments data in the PC forum, you would be doing good to get 0.1 +/- 0.1 degrees or 0.0 to 0.2 total toe in the real world. Your best bet would be to find a competent shop, tell them what your goal is and ask them how accurately they think the can set it. A good shop will be able to set it a lot tighter than Toyota's green zone. The only reasonable way I am aware of to adjust the rear toe and camber is with shims.
Thanks, xs650! I like my Toyota dealership in general, but was pretty disappointed by what they told me about the alignment. From what I had read online, I also felt they should be able to do better than just trying to get it into the green. Now I have a better idea of what to ask for, and I think I'll call around to a few places before deciding where to go. Thanks again!
