Tires: tire rotation, pontiac montana, rear tires

Question
I have a 2002 Pontiac Montana.  I took it in today for some maintanence and they did a tire rotation. When I picked it up the steering wheel felt really weird.  It jerks back and forth, not really vibrating, more bouncing.  I took it immediately back and they said it was because the tires were rotated and they were worn differently.  He thought it might stop after a while. He offered to put the tires back where they came from, but said it wasn't dangerous.   Sounds strange to me.  Would you agree?

Answer
Denise,

I'm going to make a number of assumptions.

1)  That all 4 tires are identical - same size, make, model

2)  That it has been many, many miles since the tires were last rotated - meaning they were long overdue.

If those 2 things are true, then it is quite likely that the rear tires had developed irregular wear - partially because they haven't been rotated enough, and partially due to misalignment.  When they were moved to the front  When the tires were moved to the front, the irregular wear can be felt through the steering.

Nothing to worry about except it points out the need to rotate regularly.

But there is one other possibility that needs your immediate attention.

If the "bouncing" is a "bounce - pause - bounce - pause - bounce" kind of thing, that's OK.

But if the "bounce" is a "bounce - pause - pause - bounce - pause - pause - bounce" kind of thing, especially if the bounce seems to be in only one direction (either left or right), then you may have a separation.  If the bounce is how I described it, then IMMEDIATELY take the car to a tire shop and have them look at it - and perhaps drive it.