2005 XK8 Help...
 

Recently started this slight "push and pull" feel periodically at 40mph plus, or when most noticeable. Its subtle, but can be felt. Mechanic test drove it and noticed it, but didn't know what it could be. Thoughts?

Thank you.

Few more details needed but could be gearbox ATF
 

Any more car details? Did you run an OBD check for codes? Any funny noises, ie engine misfire, or knocking ie suspension, or rumbling noises ie wheels.

First thought is that it’s time to check the gearbox and renew the Automatic Transmission Fluid (ATF)

Tommy,

I had something similar when one of the rear wheel bearings went bad. Especially noticable with cruise on, climbing/descending small hills.

Probably something else for you but I figured I'd share. Hope its something simple.

John

Mechanic said he reset everything to factory settings, whatever means. No funny noises or otherwise. I'm not a car guy. Thank you for your help!!!

How about some simple car history?
 

Tommy,

No problem..What’s the mileage? Is it a summer only car... ie has it been stored during the winter? Do you have simple car history including facts about what work has been done to the car? Any service history?

Old cars arts tend to have old car problems such as wheel bearings, rotten rubber etc. Don’t believe it when they say the transmission is sealed for life. Rear diff fluid and gearbox ATF needs to be renewed.

I'll pull recent paperwork on service history in the next day and post.

Car has 130k and used daily up to 30 miles of mostly highway driving. Car is a convertible, ives in SoCal and always sleeps in garage.