suspension - what else is there?

[northern piper]

Hey

So I've just spent my morning replacing the rear shocks on my 2000 3.8. As it turns out., the right rear shock had a wear mark on it from rubbing of the emergency brake cable. My wife is the primary driver and she said that she felt the funny vibration. Anyway, I replace both of them. Now onto the rest of my question. The van now runs fine and I plan on replacing the sway bar bushings as they're a tiny bit worn but everything else seems good. I have replaced lower control arms, struts, sway bar links, inner/outer tie rods.. but the front still feels a bit loose to use a nascar expression. What else is there? Motor mounts? I did have the recall done on the sub frame...

any thoughts?

[phil-l]

Any possibility it's a tire problem? I've had front-end vibration in the past that disappeared when the tires were replaced. One possibility here is that you've thrown a wheel weight.

Was the front end recently aligned (I presume you did so after other front-end components were replaced) - by a shop you trust to do a good job?

I can imagine engine vibration causing the front end to feel loose. Has anyone done motor mounts? How hard are they to replace?

[Windstartled]

Originally Posted by northern piper

What else is there? Motor mounts? I did have the recall done on the sub frame...

any thoughts?

Check CV joints and main subframe bushings (aka "donuts") at the bottom, Even if Ford replaced the subframe it doesn't mean they put in new main bushings. If you still have the originals they are probably rock-hard by now. This makes a major difference in ride quality and body rattle levels. The donuts are usually replaced along with motor/tranny mounts because it is part of the same process (see below). If you don't want to tackle this you should at least make sure the main subframe link bolts are tight, loose subframe bolts make steering mushy and "weavy", the car sways when turning.

Motor and transmission mounts should be checked as well, if they are worn the engine shakes and rattles on rough surfaces and you can feel this in the steering wheel. This cannot be too good for the engine.

Replacing the mounts is definitely not an easy job, in fact it's 44-step process. That's right, forty-four. On top of regular tools and jacks it requires the use of an engine support brace, 2 engine lifting brackets (these are used to hang the engine to the support brace) and a plateau-type transmission jack/lift is required in order to lower the subframe once the link bolts are removed, to gain access to the engine and transmission mounts. For the backyard mechanic this is easily a 10-hour ordeal, but most shops will do it in two.

Another option is to take the van to a DIY shop to do the job yourself but with access to proper equipment and lifts, it could be done in about 3 hours. The latter is my favorite because you have full control over what is done and can inspect your vehicle closely while you're at it, of fix stuff you keep postponing doing at home on account of limited equipment.

The above is the reason why older cars always seem to rattle a lot more than new cars and handle poorly on rough roads even with all-new suspension parts installed. Most people simply do not know about bushings and engine mounts being a factor in ride quality and noise levels. It's like tires. Many drivers will complain their vehicle has acquired a harsh ride not knowing that driving with balding tires means progressively less cushioning between the road surface and the steel belting, which cause more vibrations to be transmitted to the wheel and from there, to the frame and occupants.

[Jsaw]

Does it only feel loose or shake at higher speeds? If your answer is yes, then i agree with Phil about the tires. But if the tires are out of balance its really hard to notice while doing normal city driving. Hop on the highway and see how it feels when you get it up to aroun 80-100 km/h.

Maybe a little more information on when she is experiencing the shaking and we can help some more.

-J

[northern piper]

hey guys

yep, for sure it's not tires. I just replaced my 4 snow tires today with the almost new all seasons I run in the summer and the ride's the same. I really do believe it's the sub frame and motor mounts. The van when going 20 km over a somewhat bumpy road or train tracks just kind of creaks and rattles.

I have a 2 post lift in my garage so I'm pretty lucky from that stand point. I've never done the "donuts" but am betting that they're pretty dried and compressed. I'll have to look into that whole procedure. Is the 44 step repair available anywhere? I have alldatadiy (and admittedly haven't looked there..) but I wonder if all the other tools might make it too crazy a job to do.

[12Ounce]

I've replaced the sub-frame donuts and motor mounts @ 216k miles .... just because I was in there doing other things. I never convinced myself that I did that much good ... the used components looked pretty good.

Another area to suspect/inspect is the coupling between the steering rack and the steering column. Ford wants you to buy a new bolt for this area ... and to torque to (??) foot lbs. I just don't remember the number. Anyway this is a pretty important connection.

Also the rack itself ... is it worn? Difficult to inspect without it being removed from the car ... but its possible. At 330k miles, I think I'm on my third, maybe forth, rack.

[northern piper]

The thing with the van is, the steering is pretty smooth and it doesn't pull to one side or another, no slop in the wheel. The best way I can describe it is similar to when the stabilizer bar bushings are worn. You get this sort of double clunk that's not metallic in sound, just like (duh) something metal held by something rubber is a bit loose.

The van has 175k km on it so not super high milage, tho most is around town short trips not highway.

I'd love to hear more about your sub frame motor mount bushing replacement 12ounce. Did you ever post about that?

[12Ounce]

Originally Posted by northern piper

......
I'd love to hear more about your sub frame motor mount bushing replacement 12ounce. Did you ever post about that?......

It was a while back. I did make an extensive posting about replacing the transmission which had failed ... and my rebuilding the engine, which I just wanted to do since there had been a high-temperature event in the past. The subframe, engine, tranny, axles, steering rack were all lowered at once. So all the mounts were very accessible at the time. I don't remember ever mentioning mounts in the post.
.
http://www.automotiveforums.com/vbul...d.php?t=890799

[Windstartled]

Originally Posted by northern piper

I have a 2 post lift in my garage so I'm pretty lucky from that stand point. I've never done the "donuts" but am betting that they're pretty dried and compressed. I'll have to look into that whole procedure. Is the 44 step repair available anywhere? I have alldatadiy (and admittedly haven't looked there..) but I wonder if all the other tools might make it too crazy a job to do.

The 44-step procedure is in the reference Ford shop manual used by dealership techs. I was given the DVD by an acquaintance who works at a dealership, I don't know if it's available for sale to the public but there are torrents of alternative sources for it if you get my drift. If you can't find it PM me.

The step-by-step repair procedures for just about any issue are extremely detailed, perhaps a tad bit redundant with statements such as "use a wrench to remove the bolt" -what tech wouldn't know that?- but better TMI than not enough, right?

The donut job has to be done in conjunction with engine mounts replacement, as they are part of the same vibration dampening network. I you have bad mounts replacing the donuts alone will not have a dramatic effect on ride quality but frame rattle should decrease. It's pretty easy to determine if mounts are in need of attention. Just lift the front of the van, remove the front wheels and look at the mounts. If the metal casing is rusty and falling apart then the rubber buffers are likely damaged as well.

[olopezm]

When you replaced the struts, did you inspect/replace the strut mounts too?.

When I had a bad one it would make a squeaky-thumping noise.

Also, an incorrect alignment can cause the steering to feel a bit loose or move too much with even slight bumps.

Oscar.

[Windstartled]

I find troubleshooting front end suspension noises particularly frustrating at times. It seems that no matter what the source of the problem is, once the noise reaches the cabin it is so muffled it sounds like plastic thumping against plastic no matter what, just dull clunks. The only noise I can easily identify is brake pads knocking when you forget to put in the shims, what wife refers to as the "jalopy rattle", which of course has nothing to do with the suspension.

Would be great to have a pair of bumpy treadmills to put under the front wheels as a crude suspension diagnosis system and be able to observe the suspension as the van "rides" the bumps. Once I thought about removing the strut and wiggle the wheel up and down to see what scrapes, rubs and bangs against what but after some experimenting with this at a junkyard I figured it only covers a narrow range of possible issues and may not be worth the trouble.

[northern piper]

it's exactly as you say... very non-specific, just a general loose sound if I can say that. I'm going to replace sway bar bushings tomorrow and while they're worn, I'm not expecting much. I'm leaning towards the motor mounts, donuts as the collective culprit.

anyone have a reliable, hopefully fair priced, location for the donut bushings (2 per side) plus the motor mounts? I shutter to go to the dealer but can't seem to find much info out there.

[12Ounce]

You may be very surprised how much the bar bushings control.

[Windstartled]

Originally Posted by northern piper

it's exactly as you say... very non-specific, just a general loose sound if I can say that. I'm going to replace sway bar bushings tomorrow and while they're worn, I'm not expecting much. I'm leaning towards the motor mounts, donuts as the collective culprit.

anyone have a reliable, hopefully fair priced, location for the donut bushings (2 per side) plus the motor mounts? I shutter to go to the dealer but can't seem to find much info out there.

Don't get fleeced by the dealership. You should contact a local brick-and-mortar OEM parts supplier for the donuts, even if he doesn't have them he should be able to point you in the right direction. Motor mounts are easy to find online.

BTW Northern Piper I replied to your PM but have no idea if it worked, my reply seems to have vanished in thin air after I hit the Post button. Just let me know.

[Windstartled]

Originally Posted by 12Ounce

You may be very surprised how much the bar bushings control.

Sway bar? Yes I agree it's the best place to start. Then control arm/ball joint, tie rods, strut. I was told that another source of thuds is that plastic sheathing over the coil spring but fixing that would require installing new springs, not a procedure I am fond of to say the least.