How to check "air ride" suspension - looking to buy used Town Car

[us3r123]

Hello,

I am looking to purchase a mid 90s Town Car, I know that the air ride suspension is a known issue and can be expensive to fix. Are there any early warning signs? Any other known issues to watch out for?

Thanks!!!

[All2kool]

Originally Posted by us3r123

Hello,

I am looking to purchase a mid 90s Town Car, I know that the air ride suspension is a known issue and can be expensive to fix. Are there any early warning signs? Any other known issues to watch out for?

Thanks!!!

If the Compressor stays on for more than 10-15 seconds or so when the key is turned to ON or if the Compressor comes on while the vehicle is parked, this can indicate an air leak. Never fret though - replacing the ARS with Coil Springs is something a 16-year old can do in the driveway in less than an hour and the parts are less than $80. Repairing the ARS is an exercise in insanity if you ask me. If an Air Ride Suspension is so great, it would be standard on all cars; just as ABS and Air Bags have become.

Converting from ARS to Reliable Coil Springs

[homeskillet43]

Never never never convert. air suspension is the best suspension for the town car. i converted once before, and hated the idea. the suspension is not that difficult to fix if something goes wrong. here is a tech tip that works out greatly if anything goes wrong, Use this tech tip http://www.lincolnsonline.com/tech/00061.html.

[All2kool]

Originally Posted by homeskillet43

Never never never convert. air suspension is the best suspension for the town car. i converted once before, and hated the idea. the suspension is not that difficult to fix if something goes wrong. here is a tech tip that works out greatly if anything goes wrong, Use this tech tip http://www.lincolnsonline.com/tech/00061.html.

If ARS was so great; I'd be on all cars, just as ABS, SRS and Power Windows are these days. Several members on this forum thought they had ARS until they looked under the only car to discover otherwise. Two Reasons to convert: 1. When your ARS fails, you'll be getting towed or driving like you live in the 'hood. I've never seen a Coil Spring failure - ever. 2. No single part of a failed ARS is less expensive than replacing the system with with Coil Springs. I guess if you have money to burn and expense is of no concern, sure, replace the ARS. Start with a $300 Compressor, $300 for Air Springs and another $500 to have it all installed. Or spend $80 and 55 minutes in your driveway and be done with it.

And before you chime in and say the ride quality is diminished, well, that just isn't true do any degree. The ride is actually a little better as Coil Springs provide a level of side-to-side stiffness that an Air Spring does not.

[Blue)(Fusion]

Originally Posted by All2kool

If ARS was so great; I'd be on all cars, just as ABS, SRS and Power Windows are these days. Several members on this forum thought they had ARS until they looked under the only car to discover otherwise. Two Reasons to convert: 1. When your ARS fails, you'll be getting towed or driving like you live in the 'hood. I've never seen a Coil Spring failure - ever. 2. No single part of a failed ARS is less expensive than replacing the system with with Coil Springs. I guess if you have money to burn and expense is of no concern, sure, replace the ARS. Start with a $300 Compressor, $300 for Air Springs and another $500 to have it all installed. Or spend $80 and 55 minutes in your driveway and be done with it.

And before you chime in and say the ride quality is diminished, well, that just isn't true do any degree. The ride is actually a little better as Coil Springs provide a level of side-to-side stiffness that an Air Spring does not.

Well ride quality can be diminished based on the coils used.

If I had a car with ARS installed, I wouldn't change to coils. I enjoy it on my dad's '99 HPP Crown Vic over my poverty coils.

And coils can begin to sag over time, so they don't last forever either. But like said above, coils are significantly cheaper. I have seen a coil fail, but only once - and it was due to improper installation.

And coils don't offer any better side-to-side stability. If you ever took out the rear control arms, you'd see that the axle will move pretty freely side-to-side. I was able to move mine several inches side to side (with coils, not RAS) with little force when installing my new rear control arms.

[All2kool]

Originally Posted by Blue)(Fusion

Well ride quality can be diminished based on the coils used.

If I had a car with ARS installed, I wouldn't change to coils. I enjoy it on my dad's '99 HPP Crown Vic over my poverty coils.

And coils can begin to sag over time, so they don't last forever either. But like said above, coils are significantly cheaper. I have seen a coil fail, but only once - and it was due to improper installation.

And coils don't offer any better side-to-side stability. If you ever took out the rear control arms, you'd see that the axle will move pretty freely side-to-side. I was able to move mine several inches side to side (with coils, not RAS) with little force when installing my new rear control arms.

True, that is why you should retro-fit with quality Moog Variable Rate Coil Springs. I don't advocate retro-fitting a perfectly good and functioning ARS with Coil Springs; but when you start to see the ARS fail, as when the Air Compressor comes on in the middle of the night repeatedly, then it's time to consider this inexpensive conversion. I don''t think Coil Springs sag over time but I do believe the Shock Absorbers will contribute to what you say. Yes people, if you have ARS, you still have Shock Absorbers. Anything installed incorrectly is likely going to fail. By the basic physics involved, a Coil Spring has to provide more stability, this cannot be argued with as it is a solid construct of metal; not an air filled rubber bag.

[Blue)(Fusion]

Originally Posted by All2kool

By the basic physics involved, a Coil Spring has to provide more stability, this cannot be argued with as it is a solid construct of metal; not an air filled rubber bag.

The ARS is still limited in the side-to-side motion since the ARS is similar to a piston in a cylinder. The piston is bound by the sidewalls of the unit. They can move side-to-side but no more than coils.

Besides, coils or ARS, other suspension components should be taking care of the side-to-side movement. Watts linkage, sway bar, control arms, etc. After installing my 17mm sway bar from a CVPI, my rear end no longer does that side-slip when I hit bumps and potholes.

[All2kool]

Originally Posted by Blue)(Fusion

The ARS is still limited in the side-to-side motion since the ARS is similar to a piston in a cylinder. The piston is bound by the sidewalls of the unit. They can move side-to-side but no more than coils.

Besides, coils or ARS, other suspension components should be taking care of the side-to-side movement. Watts linkage, sway bar, control arms, etc. After installing my 17mm sway bar from a CVPI, my rear end no longer does that side-slip when I hit bumps and potholes.

Agreed, on all points. A sway bar at only 17mm kinda makes me giggle as when I had a Porsche 951, 21mm was factory and upgrading to 27mm was what we did. Yes, I know, a Porsche Turbo and an LTC hardly compare to one and other. What is the the factory installed sway bar measurement? And where did you get the CVPI sway bar and did it bolt right on?

[Blue)(Fusion]

Civilian CVs and GMs and I believe TCs did not come with rear sway bars - and mine was practically sideways in the turns. Those that had the HPP package, had a 28mm front and 21mm rear. I think newer models might all come with some sort of rear sway bars, but I never bothered to look.

I got the 17m from a local guy who had it sitting in his garage from a CVPI that upgraded. It fit right up into the car. I just had to get the axle brackets, bolts, and speed nuts (FoMoCo), poly bushings (ENS), and end links w/ poly bushings (MOOG).

Even though it's only 17mm, it lets the watts linkage do it's job so much better and ties the wheels together enough to reduce quite a bit of sway (over no bar). And if I go 21mm, I'd have to upgrade the front bar as well unless I want a bunch of oversteer. Right now it's perfect.

Took about 15 minutes to install once I got it up on jacks. Total price was about $40. You can get a new 21mm rear bar from the dealership, with the end links and rubber bushings for about $30.

[homeskillet43]

The RAS is not that not that difficult of a system when you understand the mechanics of it. You have a compressor, dyer, and vent solenoid all in one. You have two rear air bags with air solenoids atop of them. You have one air line that runs from the front of the car to a "T" fitting. The air lines from the "T" fitting goes into the two air solenoids on the bag. Finally you have a control module that controls everything. There are simple test that can be performed to test the system. The ride quality is completely changed when you convert. When I converted it was one of the last things I wish I would have done.

You may ask, why did I convert in the first place. Lack of knowledge of the system. Just recently I had a failure with my RAS. My first issue was figuring out why my car was not lifting on the driver side. Come to find out in the installation of some rear shocks, the mechanic torched my air lines. I went to the junkyard to get some air lines ($25) off a junk car, and I replaced those lines. Now my other issue was trying to figure out why my car was throwing on the "CAS" light, and the car was not venting. I ran test after test, and purchased a new air spring solenoid ($15) and control module ($25). Here is the lack of knowledge of the system. When i removed the air compressor from the car and ran power directly to the vent solenoid (this vents air out of the system), my car would vent. So I knew it was not the compressor or the control module. The vent solenoid runs power all the time, and the control module grounds the system. I was losing ground to my vent solenoid, and found out I had bad wiring from the control module to the vent solenoid. I ran a direct ground from the control module connector to the vent solenoid, and now my system is back to running perfectly.

I know many people would say, see this is a prime example on why to convert to coil springs. My position against that is, I am constantly traveling with a heavy load. The springs could not hold my load the way the RAS does. When you understand how something works, you have a better understanding on the signaficances of it. DON'T CONVERT.

[All2kool]

Originally Posted by homeskillet43

You have a compressor, dyer, and vent solenoid all in one. You have two rear air bags with air solenoids atop of them. You have one air line that runs from the front of the car to a "T" fitting. The air lines from the "T" fitting goes into the two air solenoids on the bag. Finally you have a control module that controls everything. The ride quality is completely changed when you convert.

There is a Ride Height Sensor too. And the ride quality is NOT completely changed as you say, as evidenced by several members discovering they did not have RAS any longer once they looked under the car, when in fact they thought they did. I think the ride quality is very much changed once you experience a a failure of the RAS.

I have converted to Coil Springs and my '96 Cartier still floats down the road like it was designed.

[homeskillet43]

Sorry yes there is a height sensor on the rear of the car that sends information to the control module to let it know it has reached trim height.

Is that with more than three people and baggage? I am pretty sure that car does not float the same way. You know what, I am sure that it does not. But hey if that is whay you like so be it. I like for my cars to be orginial the way the car was designed. Millions of dollars in research and development have discovered the RAS is the best for the car. I will stick to their assumptions.

[All2kool]

Originally Posted by homeskillet43

Sorry yes there is a height sensor on the rear of the car that sends information to the control module to let it know it has reached trim height.

Is that with more than three people and baggage? I am pretty sure that car does not float the same way. You know what, I am sure that it does not. But hey if that is whay you like so be it. I like for my cars to be orginial the way the car was designed. Millions of dollars in research and development have discovered the RAS is the best for the car. I will stick to their assumptions.

I operate a Town Car Service and recently had 420lbs of people and 300lbs of luggage in the back seat and trunk respectively without any sagging or shock bottoming. The key here when retro-fitting is to use quality Moog Variable Rate Coil Springs. Of course, your Shock Absorbers need to be in good functioning order as well.

And if Air Ride was so great it would be standard equipment on all cars, just as ABS, Power Windows and SRS's have become.

[Blue)(Fusion]

It's a user preference. Yes there's more that can go wrong, but it has it's advantages or else it would not exist.

[All2kool]

Originally Posted by Blue)(Fusion

It's a user preference. Yes there's more that can go wrong, but it has it's advantages or else it would not exist.

I hardly call it an advantage. Only an engineer can take one part and turn it into 4 or 5 that serve the same exact purpose. It exist because it's a gimmick and selling point; that 'floating on air feeling only a Lincoln can deliver'.