Bad news re: differential?

[SGT John]

So the Sunday prior to super bowl Sunday I replaced my diff fluid. It almost cost me my two front teeth. I am still in pain and have a follow up next week.


The fluid seemed a little low when I drained it.

On the way to a jump Monday at about 55 I noticed a slight hum coming from the back end. On the way home from the jump, my steering feels all wrong, it's like I am driving a totally different car. You know that instable feeling you get when you drive too fast? (some of you might anyway) I feel that at 40mph now.

My concern is that maybe one of my rear wheels is spinning a little faster than the other? I don't think all this could be from throwing a weight, and I think it is highly unlikely that I did anything to throw off the alignment. I checked each tie-rod and they are good and tight. The only other thing I can think of is that this is the total opposite of the way it felt about 2 months ago when I replaced all the tie rods and the center link and steering dampner.. maybe the dampener has failed?

I got 2 new tires two weeks ago, and an alignment the week before that. I didn't experience anything funny until yesterday (Monday)

[TMAllison]

Check the rubber mount on top of the diff to the car body.

[SGT John]

Thanks for the advice. I will try to get a look under there when I get home from work this evening. Should I be looking for movement, looseness?


Anyone have more things I can check?

John

[t walgamuth]

The large a arm on the back sometimes gets too rusty and begins to fail. This will cause the car to feel as you describe. The other things you mention don't sound very likely.

tom w

[SGT John]

Terry, I couldn't see much of anything above the differential, it looked like the piece holding it in place was to the rear of it, and that was holding very solid.

Tom,
I couldn't figure out what you meant by A arm. I assumed you meant the same thing as Terry but maybe not? I couldn't find anything rusty underneath.

John

[t walgamuth]

The arm I refer to is a stretched A shape. It wrapps up to carry the outer wheel bearing and folds back under the car. It is up to maybe nine inches wide and consists of two pieces of heavy sheet metal formed and welded along the edge. It will bend if the car is slid sideways and hits a curb or it may rust and allow the outer wheel bearing to wobble. If it is failing usually your rear wheel on that side will begin to lean in at the top.

It is fairly easy to replace and can be bought reasonably inexpensively used.

Tom W

[SGT John]

Unfortunately I head to the field tomorrow morning. I'll have to bookmark this page and try to get under it when I get back in 2 weeks.

[SGT John]

I can't see anything rusted. I did notice something peculiar. My friend's 300CD has a totally rebuilt front end. If I shove it sideways at the front fender it doesn't budge.... if I do that with my 300D I can move it from side to side about an inch or two.. what part of the suspension should I be checking and how can I test it better?

[mobetta]

jack it up and pry on everything. sometimes it helps to have someone pry on stuff whiloe you look at it to see if it is loose.

also the rear subframe bushings?? they are under the rear door.

[babymog]

And tires.

[SGT John]

ETA: I just thought to add I had the half axles rebuilt last week and I still have the problem. They also looked at the differential and said everything looked good..

with a good jerk I can make this piece squeak and move outward. Is that normal? If not, how on earth do I access that area to fix it?
Just to make sure you are oriented, this is front tire suspension, I just don't know the part name.

[Magoo]

That's the front sway bar frame mount. It needs replacement if you can move the bar by hand, but by itself won't cause the whole front suspension to shift. I suspect what you need to do is replace most or all of the front suspension bushings, and possibly the rears also, based on your symptoms.

[SGT John]

All of my bushings look like they've been through hell, but I can't really find any place where there is any perceivable play.

[SGT John]

I traded my car with a friend who let me use her pickup to haul sand and rock for my patio.

When I got the car back today the handling was FINE. She swears she didn't touch anything. How strange...

[tangofox007]

Originally Posted by Magoo

That's the front sway bar frame mount. It needs replacement if you can move the bar by hand, but by itself won't cause the whole front suspension to shift.

Considering that the anti-sway bar is routed through the upper control arms, I am not so sure about that.