I dont know how better to explain this but here goes...

Sometimes when I push the brakes I feel a slight tap in the steering wheel or column. It happens regardless of where the steering wheel is. (tilt up/down in/out or while wheel is turned). It happens when slowing, or when the brake is reapplied after already stopped once.

The tap feels like the steering wheel is moving a tiny bit (millimeters), but there is no actual movement in the cockpit. My uncle told me I might need to put some grease on a U joint, but I dont want to go throwing grease on stuff without asking you guys first.

Will update if I can think of a better way to explain it.

 

I have no idea, but, when you say it feels like the steering wheel is moving do you mean it feels like it's moving around, like when you're steering it, or up and down/side to side, like when you're adjusting it?

And if it isn't moving, is it like vibrations transmitted through the steering wheel, as if you struck the steering column with a hammer?

 

^Its as if you tapped the steering column with a roll of quarters. It really is just a tap. But it only happens when braking or occasionally when crawling through a pothole. It does not physically move (like when adjusting); it is more like something else is moving and releasing tension thru the column.

 

Does it happen as you're first applying the brake, or does it happen at any time while you're holding down the brake pedal?

 

^when first applying the brake. It feels like its caused when the car is tilted forward under braking. But that doesn't make alot of sense given it can be felt even at a standstill; if you are switching back and forth from park and drive

 

I am an admitted Jaguar novice, however, if this only happens while applying the brakes, it would seem like something loose in the front end or possibly a grabbing brake. My two cents worth and may be worth even less.

 

It sounds to me like something is loose in the brake system. Maybe a brake booster bolt is loose or something. When you push on the brakes the booster (or whatever is loose) shifts slightly and you feel the vibration through the steering column. The booster is bolted to the firewall directly behind the steering wheel, so that comes to mind first.

 

I think Friarshuck is on to something.

 

Very common fault and I have replaced dozens of lower columns.
Here is what we did when these cars were in warranty. I replaced very few when the customers had to pay. Not dangerous, just annoying.

bob gauff

 

I came here to post a pic of the brake booster, and ask what i could safely disassemble to inspect...

Thank you so much above poster, I think you may have hit the nail on the head

 

well... they want 458$ for the lower steering column.

Now that I know what is the culprit I might get down under there and look at it myself.
MotorCarMan, can you tell me why the piece is defective? And why does it require a new power steering return line?

 

 

I've never replaced the line on the steering rack. The lower column fixed the 'knocking' on all the ones that had the early columns.

bob gauff

 

I have the same problem as 2000CAXK8 and thanks for the info on this lower column.