the air bags go inside the spring on the rear of the Aero.

Timbren does have out their new "rubber" compression spring, AEON Hollow Rubber Springs
Timbren Aeon Hollow Rubber Springs
look like they may be the perfect solution to the Aero or other vehicle that carries heavy loads all the time.
look like an easy job to install, just replace bump stop
http://www.timbren.com/timbren-appli...dfs/FAR001.pdf

i like to run light with soft rear end most the time so air bags for me.

 

What about the Moog's is disappointing? Do you have them on the front,rear or both?

What makes you believe that the springs you listed in the HD section are better than others? And what about them makes them better?

 

Moog has designed them for a "OEM like ride". When I replaced my springs, empty van, OEM for the front and Moog for the rear, the moogs just barely ride higher than the front. Add any weight at all (like people) and it would sag right down. The new Moogs rode no higher than the old wore out OEM springs.

The ones I listed on the HD section are heavy duty cargo type springs. They use a stronger steel and/or a tighter coil pattern.

96_4WD, great post on the Timbren springs.

But there are these that replace the original springs altogether.
http://www.airbagit.com/SearchResult...earch=aerostar

I have not installed these, but If you need to replace the springs anyway, they might be a worthwhile investment.

 

So did a little more digging on the tire issue. Switching to 15" rims can give a smoother ride(on smooth to moderate roads), and the tires themselves can handle a lot of weight, however, it is a moot point, as the most cost effective tire to use that will handle the weight (215/70/15) also rubs when you load the van down (driver side read rubs the wheel well). The added weight of the larger tires and rims also makes it more difficult for the suspension to maintain a smooth ride. You could use a lower profile tire, but those cost more and cannot as readily handle the weight, so they will wear funny and quickly. If you can lift the body with a spacer to get more clearance, then the 215/70/15 tires will work fine. It should be noted that this also partly negates the purpose, as this raises the vehicles COG, which will make handling worse, especially when loaded. And the suspension travel will be the same. Otherwise they have no advantages for handling weight. Now if you aren't going to haul more weight, just use it as a people mover, then a good shock can clean up the handling issues, and the tire should run about as smooth as the stock tires. The 215/70/15 will last longer and should wear consistently.

For my comparisons, I am going with the idea of using the 215/70/15. This tire is 2 inches larger than the largest stock Aero tire. This results in significant speedometer calibration differences, and is enough to confuse the ABS and AWD systems. This also creates the same effect as changing the gear ratio. This adds extra stress to the powertrain. The engine can compensate by changing gears, but the transmission has to deal with the added stress. This will add extra stress to the trans, especially 1st, R, and OD. This added stress partly negates the point of using a heavier rated tire. In contrast, the 27x8.5 R14 is very similar in size to the stock tire. In fact, a 225/70 R14 measures 25.5" inches across. A 27/8.5 R14 also measures 25.5" across. So you get the sam drive ratio, and you get the same total rolling distance, which is good for the ABS and AWD systems, but the 27/8.5 R14 is a six ply tire. If you need load handling capacity, it is my opinion that the 27/8.5 R14 is the best choice. As previously mentioned, the only downsides I have noticed is the increased road noise (most good snow tires and good LT tires are noisy) and the initial price tag. I think this is offset by the fact that you don't need to get new rims, you don't need to worry about rubbing, you won't throw off the speedometer, and you won't foul up the ABS or AWD systems. You vehicle will ride a little lower, which improves stability.

 

BroncoII 15x7 wheels with 215-65x15 tires, KYB Gas-adjust shocks, urethane front swaybar bushings and end links, and Airlifts in the rear springs at 35 psi. Will make a new van out of it.

 

I have the 215-65x15 tires on my moms vans, and trust you me, the handling is improved, but the ride quality is poor. The 27/8.5 R14 has handling just as good as the 215/65R15, but the ride is smoother, especially going over washboard roads, potholes, and speed bumps. The only reason to run a 15" rim on an Aerostar in my opinion is to run disk brakes all around.

The urathane swaybar bushings and endlinks is a must have though, and the airlifts in the back does help compensate for back end sag and firmer cornering. But the Airlifts also make for a rougher ride. I wish better rear springs were available. Coilover rear shocks are a better option in my opinion.

 

I recently made some suspension replacements & upgrades & want to share my experiences & results. My Aero is a 96 3.0L shorty RWD passenger van with 75,000 miles that I use as a work truck. I figure I carry 500 to 800 pounds (shelving, tools, supplies, plywood floor, full size spare, etc.) in the van on a daily basis. I moved the rear bench to the middle row position & added some spacers to the base so I can fit the full size spare under the seat. There is also a class III hitch welded under the back.

I added a rear sway bar when I first got this van 2 years ago. It's a 7/8" diameter bar from a different Ford application & it was a total custom install. All bushings and end links are urethane & it really tightened up the rear load handling compared to my previous 95 Aero (no rear bar). I towed a Ford Tempo about 100 miles with a tow bar with the 95 and the rear got pushed all over the place. I occasionally tow heavy loads in a utility trailer & the sway bar helps a lot.

The shocks all around were due for replacement so I installed Monroe Sensatrac LT shocks in the front (part number 37058) & Sensatrac Load Adjusting shocks (coil-over type, part number 58616 - set of 2) in the rear. I installed Sensatracs (non coil-over) in the 95 & was happy with them, but now I can only say "satisfied". I opted for the coil-over type shock hoping they would boost the rear ride height & level the van. The springs on the rear shocks don't seem to carry much load at normal ride height, so they didn't give the rear the lift I had hoped for. I still have the original springs all around, so heavier rear springs are next on the to-do list.

The damping performance or the rear shocks is good - no deficiencies that I can detect. The performance of the front shocks is adequate on the road, but they aren't as tight as I would like. My only real complaint is how they perform on large speed bumps (parking lot speed bumps - not traffic control "humps"). At any speed above a dead crawl, after the front tires come off the bump & the front of the van drops, I can feel the front suspension hit the bump stops. Smaller speed bumps are handled better. I know the speed bumps are there to ensure I go slow, but I have had better behavior with other vehicles.

I replaced the front sway bar end links with Moog Problem Solvers (part number K80058). These have urethane isolators in them rather than the standard rubber. They tightened up the front a bit. Not a huge improvement, but I believe the OE sway bar is too compliant anyway. An aftermarket bar is on my wish list.

I have experienced the same outer-edge tire wear problems that Khan discussed. I always attributed it to body roll & "push" in curves & turns because it always seemed much worse in the front. On the 95, my favorite tire was the Nordic Wintertrac from Canadian Tire (a private labelled Bridgestone Winter Slalom) P215/70/R14. Inexpensive, great winter performance, quiet, long-wearing & good summer performance, too. I used to put 2 new ones on the rear each fall, move the old ones to the front & run them all year. Some years they still had enough tread that I didn't need to add new ones. Sadly, they were discontinued & the replacement Bridgestone model isn't available in the right size.

The new-ish all season P-radials on the 96 when I bought it wore out frighteningly fast & developed cracks everywhere. I had one blow out at 75 mph, then over the next 4 months two started leaking through the sidewalls. Once I realized I was going to run out of "good" tires from the 95 parts donor, I started doing some research.

I am now convinced that LT radials are the best choice for these vans. In my research I found that Volkswagen Westfalia camper van owners have the same (if not worse) 14" tire problems that we do - lots of good discussion & info on their forums. The Cooper Discoverer 27x8.50R14 LT that Khan recommends appears to have been discontinued - Cooper didn't list it on their web site as of August 2010 & few places seemed to have any stock. The only LT in this size I could find is the General Grabber AT2.

While the Cooper is a 6-ply tire, the AT2 is 5-ply and is rated for 1520 pounds at 55 psi. This is slightly less than the 1554 pound rating of the P215/70/R14s. To keep the weight ratings in perspective, the GAWR for my van is 2545 for the front & 2630 for the rear. During last weekend's dump run, I weighed out at 5940 pounds with a typical load in the van (some tools & materials out, but other stuff in - including 2 passengers) and my trailer. I built the trailer to be abused and estimate it weighs 600-800 pounds empty, so with a "typical" load in the van it weighs about 5200, which is close to the GAWR max. 4 tires with a total weight rating of 6080 pounds leaves me with a comfortable margin & room for some overloading.

Since the AT2 is an all-terrain tire designed for on & off road use, I expect them to be a lot tougher than a passenger car tire. The sidewalls are definitely a lot thicker & stiffer than the P-rated tires they replaced. The AT2 also carries the snowflake rating for winter use, so they are acceptable in jurisdictions that require winter tires. The tread is really chunky so I have no doubt they will handle mud & snow very well. I find it somewhat amusing that a winter-rated tire is made in Mexico. The tread depth is about double what I see on a P-rated tire, so I expect good tread life.

Tirerack currently lists the 27x8.50R14 for $101 each, so they are also less costly than the Coopers were. I bought mine from TireTrends (currently listed at $108.95 Canadian), and with delivery it was cheaper than Tirerack (cross-border shipping & duty kills their advantage). Typically we Canadians pay inflated prices for tires (pun intended) through regular distribution channels - the AT2 was listed as a special order for $180 each where I USED TO buy my tires. It pays to shop on-line, although I was frustrated by how many P-rated tires were listed on the typical tire website when I was searching specifically for LT tires.

The 27x8.50R14 LT tires are slightly taller than the OE P215/70/R14, but there are no clearance issues. The front tires are mounted on the OE rims, but the rears are mounted on an old set of aftermarket rims with a different backspacing. I used them because it moved the tires out a little closer to the lip of the wheel well - a better match to the front - which looks better & should help stability a bit. I checked a tire mounted on an OE rim on the rear & there would be no clearance issues. My spare is still a P-rated tire, but it is for emergency use only.

I made a 1500 mile round-trip to Tennessee since I put these tires on. I am VERY impressed with them. I am amazed at how quiet they are considering how chunky the tread is. I expected them to howl, but I have to listen carefully to hear the tire noise. The exhaust on my van has a noticeable growl, and it is far louder than the tires. The van feels much more planted on the road than either van ever did on P-rated tires (the 95 started as the family truckster, so often had little load). I currently have the tires at 40psi & the ride is firm but not harsh. The tires also throw up very little water spray in the rain - more of a consideration for those following, but it keeps rearward visibility clear.

The biggest downside to this tire became evident during the drive to TN. There was a strong cross-wind for most of the trip & the van got blown all over the road. The tires also tend to wander in ruts. I attribute this behavior to the lack of a continuous center rib on the tire - it is an all-terrain tire, after all. It is a behavior I can live with & have adapted to.

One minor quibble is that the chunky tread picks up mud from the puddle in my driveway & then flings it all over the place when I start driving. On the up side, it indicates the tread clears itself well which indicates it should have good mud & snow performance. On the down side, I have mud splattered everywhere under the van and a regular reminder that I need to get more gravel on the driveway. Mud flaps will need to go on before winter.

In summary: General Grabber AT2 27x8.50R14 LT gets a RECOMMENDED from me.

 

[quote=KhanTyranitar;8102854]

Springs are slightly less supported in the aftermarket, depending on the vehicle you have. 2WD models have a descent number of options, while 4WD becomes more limited. The primary function of springs is to provide ride height and to allow the tires to move with the road surface without directly transferring this motion to the vehicle. As the springs age, they loose some of the springiness, and they sag. This reduced ride height makes it easier to bottom out which has a detrimental effect of comfort and handling.

The OEM springs are pretty good, but are expensive and are getting harder to find. They were available in both standard and heavy duty configurations, with the heavy duty units being stock on the E4WD models. In my opinion, the HD version rides better, which really means the standards are the cheaper spring. In the aftermarket, there are fewer choices. This is more so of the E4WD models. Most of the aftermarket springs are roughly equivalent. Most that are listed as a variable rate will be good at both ride comfort and moderate cargo capacity. There are many factors in a spring, and unfortunately many of them are not well publicized. I will attempt to sum up or groups the springs based on what they are good for.

Springs for 2WD
MOOG (2WD only) Variable load, available for front and rear
AC Delco (2WD only) Variable load, available for front and rear
Husky (2WD) Variable load, available for front and rear
Raybestos (2WD) Heavy Duty, available for front and rear

Springs for 4WD
AC Delco (4WD) Variable load, rear only
Husky (4WD) Variable load, available for front and rear
Raybestos (4WD) Heavy Duty, rear only

While it seems the options are limited for heavy duty upgrades, don't loose hope, you can use just about any spring and use other upgrades with them to increase load handling. One such upgrade is the coilover shocks listed above.


Hold the phone. The first place to look for springs is not a tire place or an auto parts store, but to consult your local balcksmith. Huh? Blacksmith? Yep, the trade is still around and they can make you any dog gone spring you want. Many of these places have been in business since or even before Henry was selling model T's.

Here is an example for the Sacramento CA area: Leaf Springs - Hanley's Blacksmith and Spring Shop - Sacramento, CA

I like the last line "If we don't have it, we can make it." Note I am not endorsing this or any particular shop, but rather the trade in general terms.

Myself I have never needed to have any spring work done, or if I have needed it I suffered, but I have had friends that have driving styles where they abuse their vehicles and have broken springs and swear by the work that get's done.

I have a friend who was a commercial fisherman. Some of his friends were going to try to hook a great white shark for the local aquarium, but tackle was a problem. The blacksmith in San Francisco sent the fisherman to the wrecking yard in search of a torsion bar off an old Chrysler, and the blacksmith made them a shark hook that they used a live pig for bait.

For the journeyman blacksmith, a spring for a minivan should be no problem. If you want it stiffer, taller, shorter or softer they should have no problem in giving you what ever you want.

 

For tires, I use Firestone Destination A/T, size 225/70/14, on my '89 extended Eddie Bauer. They are LT rated for on and off road use. They are getting rare to find in this size, but seem to be still available if you look hard. They have an aggressive tread, so, although you lose about one mile per gallon fuel economy, you can hit a dirt road anytime, deal with occasional snow or heavy rainfall without losing traction. A fair trade when you're dealing with unpredictable BC Coastal weather, like I do.

One thing I'd like to do is add a rear sway bar and upgrade the rear shocks to Monroe Sensatrac Load Adjusting. It would be nice to tighten up the rear end handling a bit, although my rear springs aren't sagging yet (relatively low mileage and light usage for the vehicle age).

Cheers, Mike

 

I'm not too impressed with the Sensatrac dampers; they must be tuned for a cushy ride. When I first installed them, they felt like they provided better control of rebound than the stock Ford dampers. But after a few months, they felt like they lost seal, or something. I have a simple reference: There is a stretch of road that I go over regularly with a bump in it. If I hit it at 70 mph, the van will bounce up and down for a certain number of cycles. When the Sensatracs were new, the bounce were damped out in much fewer cycles. But the bounce cycles started to increase after a few months, until they settled to about the same pattern as the stock dampers had.

Some time in the future I will install the KYB Gas-Adjust dampers, and see how they behave.

 

Yeah, I have had bad experiences with all the Monroes I've ever used. All of them failed prematurely. On my mom's van, they lasted about 3 weeks before they rode softer than the old ones did. We used the Sensatracs. On my Mazda Pickup, I used the Reflex, they lasted about 2 years, which was about 15,000 miles.

I have had the KYBs on my van that got wrecked December for about 90,000 miles. They still rode like new, and I know because I had much newer ones of the same shock to compare to. I know own the comparison vehicle. Running the KYB Gas-A-Just for the increased firmness.

 

According to the Firestone website, the 225/70/14 Destination A/T is a P-rated tire, not an LT (click the SPECS tab at the top to see the sizes):
Destination A/T: Firestone Tires

The Firestone Destination LE 225/70/14 is also P-rated:
Destination LE: Firestone Tires

This was the frustration I encountered looking for an LT tire to fit the Aerostar; despite only following links for "Light Truck" tires, I was presented with P-rated tires at almost every tire manufacturer and/or tire retailer website I browsed. The General Grabber AT2 27x8.50 R14 was the ONLY true LT tire that I found that was suitable for the Aerostar.

And I am still VERY happy with them.

 

Ok, just some follow up. As you know I have used the aftermarket (Moog) coils springs and was dissappointed. They rode lower with no load than my worn out factory ones. I then installed the Air Lift kit inside the springs, which did not help with unloaded ride height, but did limit how much it could sag, and dramatically increased roll stability. While I never had a serious failure with the Air Lift kit, others have reported the bags rubbing through or otherwise bursting. I got mine with the on board compressor, which was convenient, but pricey.

On my newer van, I am taking much of what I learned from the past and seeing if other approaches work well. I have now tested the Monroe Coilover Shocks. They are basically a Sensatrak with a spring that is part of the shock to supplement the stock spring. So how well does it work? Well, for starters, Monroe claims that you can add 1500 lbs more weight and still ride level. The only way I see that as possible is if that weight is centered between the front and rear axles. While the ride height unloaded and lightly loaded is great, it only takes 500 lbs in the back cargo area to sag. By 1500 lbs, you are almost sagged to the stops. In other words, this approach is not nearly as effective as Monroe claims. To add to this, the Sensatrak shocks used have poor damping strength. This means that if you have any real weight, and you are going over rough roads, the van will start bouncing around.

So my summary of the Monroe Coilover shocks? They are good at restoring factory ride height with worn factory springs, and can add some weight bearing capacity, and improve handling, but their claims do not line up with reality. Again, Monroe has failed to actually understand the requirements of the application, and their efforts fall way short. Combined with the fact that the shock itself is quite soft, I would say these are not the best upgrade if hauling heavy loads is your goal, but should work well at restoring the vans ride comfort as a people mover. I did have several problems with the shock mounts themselves as well. The upper shock mount due to corrosion and the added strain of the coilovers ended up breaking, and the others needed to be reinforced as well. Repairs and reinforcement were easy tasks for the muffler shop, they just welded washers of the right size to build up the thickness of the shock mounts.

The next upgrade I am going to do, which I need because I haul heavy loads very often, and also need to pull a trailer frequently, is going to be the Timbren air stops. These should work a lot better than the coilovers, and should also be much better than the Air Lift kit. They will also be very easy to install. I will let you know how they do.

Next I need to upgrade my brakes. That will be another write up. I've learned a couple things from my Mom's '95 which has rear disk brakes.

 

If you want to get serious with coil-over shocks, get serious:

QA1 Precision Products DS602 - QA1 Proma Star Coil-Over Shocks - Overview - SummitRacing.com

I run the 14" version of this on my Mustang.

They also have a double-adjustable model:

QA1 Precision Products DD602 - QA1 Proma Star Coil-Over Shocks - Overview - SummitRacing.com

QA1 makes a wide selection of springs for these dampers:

QA1 Precision Products - 14.000 in. - Coil-Over Springs - SummitRacing.com

You can measure how much your van sags with the primary springs and your heaviest load, and figure out which additional spring you need to keep from bottoming out. Now that you've modified the shock mounts, they should handle the added load. Note that this assembly will be at least 3.5" diameter, so you may have to modify some things to get it to fit.

On the other hand, with the amount of heavy loads you plan to carry, you might consider a full size van with a real frame.

 

Just because I've modified the mounts doesn't mean they will take it. The shock mounts are not meant to take the full weight of major loads. That is an excellent link though, If I were to do it over again, I would not use the Monroe units. However, what assurances do I have that the QA1 is a good shock?

Why would I consider a full size van? The loads I am hauling are still well within the Aerostars weight limit, I want the ability to carry at least 5 people, and I must have AWD or 4WD. I prefer the lower ride, half ton vans and larger ride high, which makes loading and unloading that much harder. I've thought about that, the Aerostar is still the right vehicle for my needs, I just need a more substantial suspension, and better rear brakes. If I ran a half ton van, I would have to hunt down the right seats, I would loose the AWD, my tires would cost more, my brakes would cost more, my repairs would cost more, my fuel economy would go down, and it would be way too big 90% of the time.