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I am considering buying this Fifth Avenue. Looks OK, but I am concerned about the saggy rear end. I regularly see Fifth Avenues like this and I wonder what causes this? Is it just because the airbags from the adjustable rear suspension just discharged (A-la like how the Imperials look like lowriders of not driven in a while) or is it something more serious? Is it worth looking at?

http://detroit.craigslist.org/mcb/cto/1960390483.html
 

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There were two suspension under these cars.
Base on the Fifth Avenue was conventional front struts, rear coils and automatic air adjustable shocks (basically a conventional air shock with a height sensor). It's easy to install regular manually adjustable air shocks.
Upgrade was the full air suspension with a bad at every wheel, front and rear. Not hard to convert, but you need strut assemblies for the front, coils and conventional shocks for the rear.
 

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The suspension issue is most certainly to do with leaky air shocks or air bags. What you'll need to do is find out what system the car has - rear only load leveling was standard, full air suspension was optional.

If the car has the rear only system and the shocks won't hold air, you can convert to standard shocks and springs without too much of a cash investment. The rear springs need to be swapped to either Dynasty springs or new variable rate springs, and then you can use normal shocks. While you can do the shocks without doing the springs, the rear end will bottom out easily.

Retrofitting the full system is a much more involved job, but also possible. You'd need to swap the rear springs, shocks, and axle beam (the air bag system uses different spring mounts IIRC) as well as both of the front struts.

From the pics, I don't think this car has the full air suspension. The saggy rear end is most likely due to leaky air shocks. Often the compressor will burn out from running too often... when you look at the car, start it up and listen to hear if the compressor comes on (you'll know when it runs - they're not that quiet). Then see how quickly the rear end comes up, if it does at all. Sometimes, you can get away with replacing the compressor and the shocks will still hold enough air to get by for a while. The retrofit to standard shocks and springs is inevitable though - you can't get the right side air shock at the dealer anymore (and it was profoundly expensive when you could).

I should also mention - if the air shocks are bad enough, bottoming them out can get them to seize. The ride won't be pleasant if that happens.
 

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I agree with the above on the load leveling conversion. Well worth it.

Especially since in the photo I see this car has taken a mild hit in the passenger rear quarter panel. The compressor for the load leveler is mounted directly behind the side marker lamp there. If you were to lay down, and look up behind the rear wheel, you would see it below and to the rear of the fuel filler neck. It's possible the compressor was damaged, or a line pinched when this happened.
 

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It's possible the compressor was damaged, or a line pinched when this happened.
Another very good possibility... the load leveling computer, relays, and all wiring is right there in that area too.

Used working compressors can be found fairly often in the salvage yards, but you really need to bring a multimeter or continuity checker to test them. In my experience, you have a 50/50 chance of finding working ones. I just unplug the 4 pin connector at the compressor, use the continuity tester between the two thicker wires, and if I get a beep the compressor is probably ok. I have three working compressors on the shelf right now - I've stopped buying them because I never find good air shocks to go with them. Many times someone will retrofit the car to normal parts but leave the compressor there... often they'll be in working order, often they won't be.

Replacing the compressor won't do any good if the shocks are bad. If the compressor isn't running, the first thing I'd do is get the car up off the ground with the rear wheels hanging. That will stretch the shocks out and let you see how badly the shocks' air bladders are splitting or cracking. If the rubber is noticeably cracked and in bad shape, don't bother with the compressor - just retrofit to normal shocks and springs and get the load leveling parts out of there. But if the rubber isn't bad and the compressor is dead, you're welcome to one of my compressors. I'm sure I won't use them. Even the Imperial's system is due to be retrofitted soon - the system still works, but the shocks are getting leaky.

But like I said - the retrofit is inevitable. Either it gets done now, or later with these cars, but it'll need to be done sometime.
 

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We had a similar problem with our 95 Grand Marquis (air suspension -rear only) - had it repaired (new bags/compressor) - then it failed again in a few years - stuck up high, then slowly discharged and never attempted to re inflate (bad computer) - just had the standard shocks/springs/conversion put in about a year ago - rides better and no butt dragging. And - it cost less than repairing the existing system - I'm thinking in the neighborhood of $200. I'd definitely go 'standard' suspension.
 

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Is it possible to use one of those small emergency 12v compressors in it's place? Have a 91 5th Avenue that the compressor froze up. I know this is an old forum but didn't want to start a new thread. Thanks, Goonior



07 Sebring
05 Magnum RT
91 5th Ave
79 Cordoba
 

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The factory air compressor has a dryer bolted to it so moisture doesn't accumulate in the shock bladders. I'd go with a factory unit only... good news is, the 2 wheel air shock system was standard on the Imperial, Fifth, and New Yorker Landau, so there are a lot of them out there in the yards. The system was optional on the Dynasty as well. I personally have 2 spare working ones, if memory serves. I bring a DMM to the yards and check the motor wires for continuity to find the good ones. They're out there.

That said, if your compressor is blown you have a very good chance it blew because the air shocks are leaky. Very, very common problem... after all this time, the air bladders dry out and crack and leak. The compressor runs all the time and then burns itself out. You can't get them new anymore (at least, not the right side shock) unless you happen to find NOS parts on eBay at just the right time, so the usual approach is to swap over to Dynasty shocks and springs with a 1" spacer or so on said springs to bring the ride height up a little.

It's also possible to plug all the leaks in the old shocks with Slime tire sealant... I did that for a year or so on the Imperial until I could find new air shocks for it.
 

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I realize this is a pretty old thread, but I suspect my new-to-me 1987 Town & Country wagon has self leveling rear suspension, which I was concerned about keeping going - until I found this Monroe air shock: MA784 :: e-Catalog :: MONROE® SHOCKS & STRUTS

It would appear to fit the self leveling system, but I'd like to know if anyone has used them with any success.
 

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I realize this is a pretty old thread, but I suspect my new-to-me 1987 Town & Country wagon has self leveling rear suspension, which I was concerned about keeping going - until I found this Monroe air shock: MA784 :: e-Catalog :: MONROE® SHOCKS & STRUTS

It would appear to fit the self leveling system, but I'd like to know if anyone has used them with any success.
The problem is the Chrysler shocks have a sensor installed in one of the rear shocks that shuts the compressor off when the proper height is reached. You have two alternatives:
1) Install aftermarket air shocks like the ones you lined to, but manually adjust the pressure as needed with an air compressor to keep the car level.
2) Adapt the height sensing valve to an aftermarket shock (assuming the rest of the system in the car is good), like this:
Load Levelling Suspension Repair (alternative)
 

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The problem is the Chrysler shocks have a sensor installed in one of the rear shocks that shuts the compressor off when the proper height is reached. You have two alternatives:
1) Install aftermarket air shocks like the ones you lined to, but manually adjust the pressure as needed with an air compressor to keep the car level.
2) Adapt the height sensing valve to an aftermarket shock (assuming the rest of the system in the car is good), like this:
Load Levelling Suspension Repair (alternative)
Thanks for the link, much appreciated.
 

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IIRC that system uses a separate height sensor not built into the shock, much like the 1987 New Yorker I scavenged for parts from once. I pulled the height sensor off that car to modify the Imperial with just in case I never found decent factory air shocks. Ended up not needing it. Probably still have it around somewhere.

Might want to check for that. The one I have is a little box with a linkage that connects to the rear axle.
 
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