Alignment Check Can Confirm If There Is a Control Arm Mix-Up

Dear Car Talk

Dear Car Talk | May 11, 2017

Dear Car Talk:

I recently replaced the inner and outer tie rod ends, ball joints, axles, CV joints, front tension strut bushings, and control arms (with bushings and ball joints) on both sides of my 1993 Ford Taurus GL. I also did a rough alignment afterward. The shock/strut assemblies were done earlier this year. I've since had the nagging feeling that I may have mixed up the left and right control arms before I installed them. I don't think they're interchangeable, because they have different part numbers (K8425 and K8427). How can I figure out now whether I switched them by mistake? -- Laura

This reminds me of the old adage about the criminal always returning to the scene of the crime, Laura. Like said criminal, I'd advise you not to go back there.

Actually, if you're lucky, there's still a decal on one or both of the control arms. Or maybe there's a part number stamped into the metal. You might be able to get under there and find a part number and confirm it that way.

But it's not easy to put them in on the wrong sides, Laura. I suppose if you really force it, you might be able to do it, but then the car would be almost impossible to drive. So if the car is driving more or less normally (or whatever counts as normal on a 1993 Taurus), you probably got it right.

If you want to be sure, take the car to an alignment shop. You definitely need an alignment anyway. A rough alignment -- where you look at the wheels and say, "Hmm, they're both pointing more or less in the same direction" -- isn't worth squat.

If the alignment shop is able to align the car, then you can rest easy, because there's no way they'll be able to align it if the control arms are on the wrong sides.

The only downside, I guess, is that you may expose yourself to potential ridicule. If you did somehow reverse everything, the guys at the shop may laugh at you. But at that point, you can either confess and take your lumps, or you can tell them you had it done at my shop, mumble something about "those morons," and throw us under the bus. Good luck, Laura.

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