As speed increases so does the need for accuracy in your carís suspension and steering components. Actually, it probably isnít surprising that the loose feeling hasnít been noticed until your first higher speed drive.
Since it is difficult to diagnosis what is wrong, it is suggested that you check or have checked for you, the obvious list of items, but also to eliminate a bad alignment.
A bad alignment can and does happen. The wrong toe setting will make a car twitchy as an example. I think it is reasonable to take the car back and discuss this with the shop that just performed the alignment.
Since your car has enough miles to warrant checking all components, this is what I would do:
First, check the tire pressure. I know but I have had cars aligned badly years ago and the tech let too much air out when the tires were warm. Obvious, but you are in a process of inspection and verification.
-Check the front wheel bearings. They would have to be pretty worn out and noisy but it you live where there are rough roads, it is a good idea
-Check the ball joints, tie-rod ends, center link and the idler arm bushings carefully
-Inspect your control arm bushings, are any cracked or otherwise deteriorated?
-Are your shocks in good shape?
-With the engine off but with the key in the unlocked steering wheel position, do you have excessive play? (Worn steering gear box and/or steering column links?)
-I would replace the four front sway-bar bushings regardless of other work performed, they are inexpensive, easy to do and yield good handling results
-Check all five links on each side. A common link to fail is the upper diagonal link. Often just replacing this link can eliminate some twitchiness, especially at higher sppeds
-Check your rear sub-frame and differential mount bushings. Often these are simply worn and wonít cause the twitchy handling you describe unless really worn, but are probably a good candidate for replacement
-Replace your rear sway-bar bushings and inspect the vertical plastic links ends from the swaybar ends to each lower rear control arm. Again, inexpensive, easy to do and yield good handling results
I am sure others have some great suggestions as well, hopefully this will get you started.
Keep us posted,
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)