Cadillac Repair: front control arm, 1990 cadillac seville, wheel drive vehicles

Question
I was quoted on a problem with my undercarriage of my 1990 Cadillac Seville. A loose hub bearing /pushing/bushing (?) rod/control Arm at $244.00 & $160.00 2 different parts.  I've never heard of either.  Perhaps another opinion is needed or is a Cadillac thing?


Answer
Hi Diane,

       The parts you are concerned about...the hub and bearing and lower control arm rod bushing have come about because of the front wheel drive vehicles. Fords use the control arm rod alot on their cars also. But not everyone uses the rod and bushing set-up.

       The hub and bearing takes the place of 2 individual wheel bearings that need to be packed with grease and are placed inside the rotor. What the hub and bearing consists of are the wheel bearings that don't need to be repacked with grease nor do they need to be adjusted, a place for the drive axle to bolt to and a place for the brake rotor and rim to bolt to. The bearings come "lubed for life" and the axle nut as well as 3 bolts are torqued to hold it in place. Between 75,000- 150,000 miles they will start to get a rumble/growl that will change with vehicle speed. There is 1 hub and bearing assembly at each wheel and that is what the wheel is bolted to.

     In an effort to save weight and increase fuel mileage the lower control arm is designed differantly also. Instead of being shaped like the letter A, it uses half of the A along with a rod that attaches to the engine cradle/frame in front. Where it bolts to the frame there is a rubber bushing that absorbs some of the movement as you drive so the ride isn't as harsh. After 100,000 miles of moveing the bushing starts to get hard and crack. Also the front end alignment is changed. So when all the parts are replaced you really should have a 4 wheel alignment done to make sure the tires don't wear prematurely. It alo helps with gas mileage when the alignment is correct.

     If in doubt that the parts are bad then by all means  a second opinion is always a good ides. If you trust the first shop is giving you the strait story and the parts need changeing then have them show you on the car where they are, why they are bad and explain what they do if my description doesn't make sense. Afterall if someone wanted over $500 dollars of my money I would want to know why also. Hope that helps answer your question. Bill