So I was sitting in the backseat of my TL and while we were going over bumps or around corners I noticed that it seemed that the back end was stepping out or going sideways slightly. I'm not sure if this is a natural thing for a TL to do I don't notice it from the driver's seat, only from the rear seats. As far as I know I have a stock suspension set up with Khumo Ecxsta ASX 235/40/18 tires. Has anyone else felt this and is it normal or does something need to be fixed?

 

That tire is XL rated so it’s reinforced, so first make certain tire pressure isn't too high as that will get the car off the ground and allow the rear to move under certain conditions. My son in law put some gigantic Michelin tires on their Hemi Grand (265/70-17) that are entirely too large along with load range E, and with 36lbs in the tires, the 5000lb Jeep will step out in rear when striking a sharp bump.

 

There was also a TSB for some '04-'05 rear axle bump stops which may be part of the problem-- see https://acurazine.com/forums/3g-tl-tires-wheels-suspension-97/too-many-04-05-owners-unaware-critical-tsb-have-done-601284/.

First, check air pressure and tire condition (both must be proper; a bubble or separated belt in a rear tire can also result in the hinky suspension response).

Second, check to see if the car is subject to the TSB.

Finally, if the tries are OK and the TSB does not apply, have a suspension shop check wheel alignment (all 4 wheels) to make sure it is proper.

G/L.