91 LeSabre front end/engine mount

I recently changed the front struts and balljoints, and front brake pads and rotors. Hacking away at the old balljoint tabs and rivets with a grinder was a pain, but the resulting torn up piece of metal makes a nice showpiece at the office. Had an alignment done the next morning.



That day while driving around for work, the car would jerk left under moderate to heavy braking, then jerk back right (straight) when I let off the brake. Not enough to immediately cause an accident, but it does require a steering correction which is now instinctive, but disconcerting.



When I brought it back to the shop, figuring they left some connection loose, they said everything was tight, and that the problem was in fact cause by a broken engine mount (right front, the one and only engine mount as the other three mounts are on the tranny). They showed me this up on the lift, and yep, it was shot. LF tranny mount rubber was also cracked and they recommended replacement. I’ve ordered new mounts and will be putting them in this weekend.



But I’m not convince that a moving engine can change the geometry of my front end. Each half shaft has two CV joints, so surely the outer end of the axle should never change orientation within the hub. I haven’t been able to get under the car to see if something is loose yet. Any clue if the mechanics are right or full of it?



Thanks.

bump

It can happen and you will know something after the engine mount is changed. The results can go either way but the CV joints do have limitations built right in. Hope it gets fixed easily.

Thanks. Is there some free play in the hub or something?