Suspension problem?

[Naio]

This is about my minivan conversion.

When driving, the van feels like it is extremely topheavy and overloaded, but it is not. My gear weighs about the same as the seats I took out, and the heavy stuff is on the floor. Nothing is in the top half of the van except a couple of pillows and hanging clothes. And my head, when driving. The topheavy feeling prevents me from driving at freeway speed.

When parked, windstorms rock the van and I find it necessary to put it up on jackstands. This is inconvenient, as it is supposed to be my daily driver! I asked in another thread about installing jacks, and that is how I came to realise the wind problem may be related to the driving problem.

I have new shocks and tires (LT BFG AT/TA, stiffish shocks, 1000 miles on each). The van is AWD. In general it is in good shape and is not a clunker.

My suspension is of the first type listed on this page:
http://www.carbibles.com/suspension_bible_pg2.html

I see that they say this type does not normally have a lot of lateral stability. Do I need a sway bar? Or is something broken that can be fixed?

Note: I try to avoid posting the make and model of this van, because I have an online stalker who has proven dangerous IRL. For those who know or can guess, please resist the temptation to post the info here. If you really need to know, you can, of course, pm me.

[j-d]

gOOgle this: "make model ride height" and you'll find a blog with detailed measurement instructions. Make = Car Brand, Model = Series Name

[j-d]

$10 spent on a CAT scale weight at a truck stop can help with your troubleshooting. The scale provides weights for Steer Axle, Drive Axle (of a semi tractor) and Trailer it's towing. Go inside (sometimes to what's called the Fuel Desk) and ask how to position such a short vehicle as a minivan that it'll capture the Front and Rear Axles individually.

Could be ALL your springs are shot and the front is sagging more than the rear. An alignment shop should check "Ride Height" before starting work. That says there's a spec somewhere that you can get and check.

[Naio]

Thank you folks, so much! Please feel free to keep the ideas rolling :),

I had a long convo with a friend who knows vehicles better than I (though motorcycles, not trucks), and who has driven my van (loaded for travel). I told him all the things you all had suggested.

His response:

He thinks the leaf springs could very well be dead, even tho rear of van sits higher than front. He says they feel very mushy.

He reminded me of something I had forgotten to tell y'all, which is the van's tendency to set up an oscillation after it goes over a bump or a dip. It feels like the road goes up and down and up and down... but really it was just one bump and the van doing the rest on its own. This is with new, stiff shocks. It's especially bad if the bump is hit while cornering.

--

I'm excited to have some ideas to try out! I do not think my tires are E rated. I thought LT's would be enough of an improvement over the P's it had when I bought it :).

I see that leaf springs and sway bars cost about the same. How do I evaluate the springs, other than how my van sits? I am wondering which to try first.

Reading van forums, I see the Hellwig sits above the differential, which is nice (I won't hit it on a rock), but there is some concern over whether/how to install it with a hitch. The Addco is slightly fatter, and sits below the differential.

As for my stalker, he is not an RVer, so I figure anyone who has been a member here for a few years is not him :).

[Salvo]

I'm not a huge fan of sway bars. The bigger they are the more you lose independent suspension. Rocking will get worse, after all the torsion bar is a spring. Wind it up and you'll get more rocking.

Are your tires E rated?

[riven1950]

I have an online stalker who has proven dangerous IRL. For those who know or can guess, please resist the temptation to post the info here. If you really need to know, you can, of course, pm me.

How would you know your stalker is not the person who is sending you a PM? Just saying, be careful!

[j-d]

U-Shape at the top of the first picture is Upper Control Arm. Vehicle looks like it's All Wheel Drive. That might limit your options for the front sway bar, but you can add a rear bar for sure.

[MEXICOWANDERER]

I've dealt with this issue so many times I lost track. When tires, shocks, springs and everything else has been examined and eliminated, it's time to start looking at a REAR sway bar. At least an inch in diameter. Adding a rear sway bar is flat-out "magic" to cure sway, leaning in curves, and instability in cross winds. You will not believe it is the same vehicle!

Google ADDCO SWAY BARS

They are located in Lake Park, FL.

The installation of a rear sway bar DOES NOT MAKE THE RIDE STIFFER! If you attemped to cure sway with stiffer springs, your rig wil ride like a buckboard.

I "discovered" ADDCO when I was attempting to tame the handling of a 400hp Sunbeam Tiger, 40-years ago. The kits are not cheap but nothing else does it nearly aa well.

[mgirardo]

Without anti-sway bars, your van will feel the effects of wind and it will definitely have a good amount of body roll when cornering. Getting anti-sway bars for the front and rear should make a big difference both on the road and while camping.

-Michael

[Naio]

Thanks, folks!

No, the rear is not lower. The rear has the suspension in the link in the OP, no sway bar. I also have some photos in another thread if you want to see.

The front is so complicated I am not sure what I am looking at! I can see what is the steering. But what is this U-shaped thing that curves around the smaller rubber boot?

[j-d]

Others posted while I was researching and typing.
We've had two Class C's, both on Ford.
On the older first one, it had only an original front bar. I replaced the worn out rubber end link parts with a hard plastic kit from NAPA and it made a huge difference. I never added more.
The second one had original bars front and rear. It took replacing both with Hellwig bars to tame the swaying. It also became MUCH steadier on the campsite.

[j-d]

I'd guess your springs could be soft, with Age and Mileage. Does one end ride lower than the other? If the Rear is low, then those springs are tired and sagging. This is a sample pic of a rear anti-sway bar from Hellwig, which is an excellent provider. The bulge in the center of the bar in the photo is to clear the differential. The two portions outboard of that bulge, parallel to the top edge of the photo, clamp to the Axle using the hardware in the center of the photo. The remaining four pieces link to the chassis. The idea is that for the vehicle to sway or rock, the Sway Bar must be twisted, in addition to flexing the springs. On RV's, notably Class C's, Front and Rear Sway Bars are very successful in improving both road manners AND stability when stopped, parked, camping.
If you're driving what I think you are, Hellwig offers front and rear sway bar kits. More vehicles come with a front bar than a rear bar, and often the front bar is puny. So it's not unusual to Replace a Front Bar with a better one, and Install a Rear Bar where there wasn't one before. The improvement is stunning. They cost about $200 each.

[mabynack]

I would have a front-end shop check the sway bars and bushings.

[Naio]

ScottG wrote:
I would weigh it. It may be a lot heavier than you think.

Good point, and it inspires two more newbie questions:

- How do I find a place to do that? I am in the middle of a huge metro area.

- If it is heavy, what do I do? I cannot realistically get rid of stuff ...this is a minivan, so it is not like I have a lot of gear :). Do I add some sort of weight-handling equipment? Like what?

[ScottG]

I would weigh it. It may be a lot heavier than you think.