Cadillac Owners Forum banner

Rear Suspension/Shocks 2001 Deville

59K views 57 replies 14 participants last post by  limoman69 
#1 ·
I have a 2001 standard Deville. The rear shocks need replacement. What are my options? Do I spend the Big $$ to replace the OEM shocks with OEM or is there a better alternative/modification I can do? I would think that the sensors and pump are in good condition, but those of you with much more experience than I do ... does this system tend to have the trickle down effect on related parts/replacements??
 
#5 ·
I just installed Monroe MA822's on my 02 Deville 2 days ago. Rockauto and some other places have these for less than $60 a pair. I have only driven it once so far but I think they ride great, and you cannot beat the price. If you search on this forum, you'll see that the AC Delcos come with the upper mount, but someone commented that the rubber seemed stiffer than the original, and that they thought it stiffened the ride. The Monroe does not come with the upper mount, so I reused the original. Also, the original air line connects right up to the Monroes.
 
#6 · (Edited)
If you were to call AC Delco, they'd tell you that there are two replacements for FE1: 504-123, and 504-547. They told me the first was the recommended choice, and 504-547 is not as high quality. This is not true, as apparently the folks that answer their catalog line are simply looking at a book and have NO IDEA what they speak. Both are the same shock absorber, manufactured by Gabriel. The difference is what comes with each one, and the price.



504-123 (pictured above) comes with new shock mounts and is supposed to be a direct fit but Domino1968 and myself had issues in that there was a lot of noise coming from the rear of the car. After consulting with Gabriel techs over the phone (AC Delco does not offer ANY tech support for consumers), they tell you that the problem is their shocks require more air than the original equipment, so one needs to replace a spring inside the dryer.



504-547 (pic above) is the same shock absorber, but comes with airline kit and the spring that goes inside the dryer that allows the correct amount of air to fill the shock absorber. This kit also costs less, and makes more sense from the standpoint of what you get, if you reuse the shock absorber mounts.

So the big FAIL for ACDelco is in not letting the consumer know that the shocks are not a direct-fit as purported. They require modding the dryer with a new spring and it is not provided in the more expensive shock (which is the same one, but supplies the rubber mounts). Very, very frustrating learning experience.

The Monroes are less expensive and come without the hassle of replacing the dryer spring. Make sure your air lines are good before you go this route (one of my lines was damaged). It's very likely that Gabriel is the OE supplier for FE1 struts too, though so consider that if you replace the front struts of your base Deville or DHS. See my "school of hard knocks" learning experience here: http://www.cadillacforums.com/forum...10996-self-leveling-rear-ac-delco-shocks.html

See Domino1968's install info here http://www.cadillacforums.com/forums/cadillac-tech-tips/209911-my-passive-shock-install.html
 
#7 ·
hmm, we've never experienced this 'noise coming from the rear of the car' that you talk about when installing the OEM (504-123)

and correct me if i'm wrong, but the 504-547 shocks have a threaded fitting for the air line, while the 504-123 has the OEM style clip-on fittings, right?

we've installed both parts on various cars over the years and the only thing we do differently when installing the 504-547 kit is to splice the air lines with a compression fitting so to add the screw on caps in that kit in place of the OEM snap style ends
 
#8 ·
The noise is from the "can" not being all the way up (inflated). Gabriel said the can should be all the way up, all the time and this should happen with 20 psi or so. The situation happens usually when the car is unloaded (no extra weight in the back seat or in the trunk). The shock absorber ends up moving up and hitting the bumper at the top, sounding like there's a loose jack in the trunk.

When there is weight in the back, and the system must raise the rear end, then the "cans" go all the way up and lift the car. At that point there is no noise, and the rear end of the car raises to remain level. The diagnosis from Gabriel is that the spring inside the dryer should be changed to one they provide with their Hijackers or in this case comes with the 504-547. The 504-123 does have the direct-fit airline fitting for the OE.. it just snaps in, and then there's the clip. Sometimes the noise isn't as noticeable (radio on, etc), but once you know what's going on you look for it and usually find it.

Another way to recreate the noise is to get in the empty car, then load the rear end... as the compressor pumps them the cans expand to the top, and at that point they "snap" into place, making the same noise. I'll see if I can take a video of it since it's perfectly visible from the wheel well.

I would rather say this is an isolated incident, and I got a defective set, but that's the same thing Domino said happened to his. He thought they had a leak and got Monroes.

I did get a new dryer, so it's possible that the spring inside it is too stiff or too soft (not sure what the difference between the original spring is and the one supplied by Gabriel in the kit, because I haven't had them side by side to compare). I'm getting the Gabriels soon and will attempt opening the dryer to replace the spring. As I said the Gabriel tech folks were the ones to tell me the problem is the spring because they require more air.

I'm going to talk to the guys at Suncore in FL that refurbish the driers to see if they can tell me how to open my drier to replace said spring.
 
#9 ·
Something's fishy: If the car is unloaded and at its normal attitude and you place added weight in the rear seat or trunk, the shocks/boots compress. The ELC senses this and restores the shock to its unloaded height, no more. If the shock inflated completely - all the way up - the car would sit with exaggerated rake and, yes, you would have bumping noises from the overextended shock.
 
#10 · (Edited)

I get what you mean, Sub, but this shock absorber design is different. Here's a pic that Domino took of the 504-123 when it was installed in his car (he since replaced them with Monroes, after concluding the shocks must have a leak bc of the noises). The design is very different than the one that the OE (In the original factory shocks, you can see the rubber boot at the bottom, and there is NO SHAFT that comes out from the top of the shock absorber body).

In these, there's a shaft on top that hides when the shock is fully inflated. In the picture above, it's completely deflated, exposing the whole shaft. The bottom part is more like what a common shock absorber looks like. This bottom part is what I meant by "can."

When it's inflated, the shaft should disappear into the "can." When unloaded and the compressor comes on initially, the can rises and stops about 1/2-1" short of the top. This leaves a 1" gap for which the "can" travels up and down with varying road conditions. When the can strikes the top, it sounds like there's a thump.

If the car gets loaded to the point where the rear is lower, then the height sensor turns on the compressor and THEN, the can rises, completely hiding the shaft, and sometimes one can hear the "pop" when it goes all the way to the top, hitting the bumper and continuing to rise the car to level. At that point there are no more noises because the air fills the chamber completely and there is no more shaft exposed.

The 00-05 does not ever have an exaggerated rake, but it does sit nice and tall in the rear. I can "trick" the shocks into filling up to the top by cycling the ignition and commanding the compressor to fill again. This causes a "pop" sound when the cans rise to the top, hitting the top bumper. At this point the car won't make those noises anymore. This fix lasts a couple of days or so.

The explanation by the Gabriel tech guys is that the air chamber in the shock requires at least 20 psi to expand all the way to the top (hiding the top shaft in the process). Replacing the spring inside the drier changes the tension in the drier somehow increasing the fill psi. Gabriel knew this would be the case with the GM self-leveling suspensions, thus they provide the spring in their brand-name kit, and they also supply this spring with instructions for the 504-547 (that costs less than the 504-123 that I got that comes without spring or airlines, but has the new mounts attached).
 
#12 ·
I still question why GM or Cadillac would purposely design a suspension that caused objectionable thumping noises when operating properly.

I just tried the KEY:ON/KEY:OFF sequence 6 times waiting 1 minute between tries. Each time the ELC system proves out (in my car) the exhaust valve then opens to restore the rear to proper height: you CAN NOT create an artificial rake in my system, and it will NOT extend to the point of "pop".........maybe the F55 suspension units are different.

FWIW I went to our local Southern States last Wednesday and loaded four 60# bags of sand into the trunk - garden "Honey, do" - the whole thing worked perfectly and the rear leveled to where it always sits.
 
#13 · (Edited)
I still question why GM or Cadillac would purposely design a suspension that caused objectionable thumping noises when operating properly.
Edit: The original part is no longer available. The replacement is different than what came in the car. I found a post through a search on the forum that mentions it. http://www.cadillacforums.com/forum...27-no-original-oem-rear-shocks-available.html

I don't think it was intentional. The reason for this problem is probably that the replacement part, is not the original equipment. Possibly this is due to bankruptcy or problems with OE design? IDK. At least they provide the spring that's necessary for the replacement on one of the kits. They dropped the ball with the other one, IMO.

submariner409 said:
I just tried the KEY:ON/KEY:OFF sequence 6 times waiting 1 minute between tries. Each time the ELC system proves out (in my car) the exhaust valve then opens to restore the rear to proper height: you CAN NOT create an artificial rake in my system, and it will NOT extend to the point of "pop".........maybe the F55 suspension units are different.
Yes, I also cannot create an artificial rake because of the exhaust valve. I can sit in the trunk and wait until the compressor kicks on, it raises me perfectly, and then when I jump off I do indeed also hear the compressor exhaust. The residual air pressure is sometimes enough to keep the cans inflated to the top (alas sometimes it's not, and the cans sit about an 1" or 2" from the top, making noise when going over small bumps.


submariner409 said:
FWIW I went to our local Southern States last Wednesday and loaded four 60# bags of sand into the trunk - garden "Honey, do" - the whole thing worked perfectly and the rear leveled to where it always sits.
Similarly, I had 3 folks in the car during a lunch at work on Friday and the car leveled off nicely like yours, and I could barely feel the difference vs. unloaded (except that there was no noise at all because the "cans" were pressurized to the top, supporting the extra weight). whereas with the old blown shocks the car would've handled freakishly with a weighed back seat.
 
#14 · (Edited)
If a picture tells a thousand words, how many words does a video tell? Turn up your speakers so you can hear the air compressor going, and the eventual "pop" on the second video.

Here is the shock absorber (left rear), seconds after key-on, descriptions are below each video.


You can see that the compressor comes on and "partially" fills the shock absorber, as you can see it rising, as it almost hides the upper shaft. But it doesn't go all the way to the top. This "gap" is what makes the noise when going over bumps.

Immediately following the initial key-on, I keyed-off, then keyed-on again, commanding the compressor to pump pressure again. You can see in the video below, how the additional air pressure fills the shock absorber even more.





Notice that there is a loud "pop" where the shock absorber fully fills with air (thanks to a second initial compressor pressurization), and it strikes the built-in stop at the top. According to the manufacturer, Gabriel, they should always be all the way to the top. Note that this pressurization that happens at startup does NOT affect ride height, because the 00-05 Deville/DHS is level when empty, without any air-lift assist. It is only when it has additional weight that the ride-height sensor, notices the lowered rear, and commands the compressor to run until it detects it is at level.


CONCLUSION.

If OE is preferred, they don't make the original part anymore. But if the AC Delco branding matters go with the 504-547 and replace the dryer spring, lines etc that come with the kit. You'll have to purchase rear shock-absorber mounts if yours are worn (unfortunately I discarded my old shocks and threw away the mounts with it, because I purchased the 504-123, else I would've probably reused them). You can also get the Gabriel HiJackers (exactly the same kit and air-lift shock absorber, for cheaper), or the Monroes which require no modification at all, and do not have this extra shaft at the top that makes the noises (they cost even less than the Gabriels).

If you get the 504-123 you will have the same shock absorber with a direct-fit air line connector (as the Monroes!), BUT it won't have the spring that goes inside the dryer. You may have the noises coming from the trunk and the useful life of it may be shortened.
 
#16 ·
It could be because Gabriel may be an OEM for AC Delco (at least for FE1) for a while. They've been making the HiJacker air-adjustable shock since 1967, according to their website. The tech guy I spoke with said the Ultra is the FE1 OEM too, on the Deville/DHS (00-05). I can't verify it, but may be able to if I purchase Ultras to replace the struts.
 
#18 · (Edited)
.....and Gabriel must get a lot of "pop" questions if that sequence is "normal". That's quite a hard thump.
You're right. With the usual Gabriel HiJacker application, the system is manually pumped via a regular tire valve (and stays that way until the user inflates them more to compensate for a heavier load or what not).

In the GM self-leveling application, the system exhausts. The drier must have some kind of role in the pressure, because the spring that comes in the kit is calibrated to allegedly corrects the PSI.

But if the system pops every time...it's got me thinking of canceling my order for Gabriels with the "repair" spring kit, and just getting the Monroes.... but I hear the monroe [front] struts are significantly firmer than OE. I wonder what kind of a balance rear monroes and front gabriels (OEM?) would create?

Currently, these Gabriels (I mean AC Delcos) are a little bouncy but the car handles really well with them, even with the soft, well worn-in stock front struts (that sometimes bottom out going over larger bumps). The Ultras in the front *should* restore the new-car feel, albeit always more bouncy due to the air-filled back shocks.

I wonder if the rears were originally manuf by Gabriel, because I read that Gabriels traditionally have had the "airbag" protected inside the metal casing, whereas Monroe has it on the outside just like the shocks I replaced did (and the rubber sleeve was cracked). Ugh... dilemmas... decisions. Any advice on that? Perhaps OE wasn't matched either... rears Monroe, fronts Gabriel ultra... that'd be odd. But it's all some kind of corporate secret (what supplier provides what etc).
 
#20 ·
Well there's no written confirmation but visually they are identical, as is the airline-kit baggie. When I talked to tech there was an air of "I know what you're talking about" and they may have mentioned it a couple of times that they were aware. However I don't want to get anyone in trouble. I was the one in trouble with the shocks and noone was there to provide any help (except them).
 
#22 ·
It could be, but since 504-547 and the Gabriel branded HiJacker for this application both have the spring, I think it's possible that they dropped the ball with the 504-123 and forgot it's necessary.

It's also possible that the 504-123 may have a smaller air bladder with the purpose of being a direct-fit replacement, but that math calculation didn't go very well. I say, from their physical appearance, they're all the same exact shock absorber. If you had both in stock maybe you could see if there are any differences (other than the threaded line vs stock original)

AFAIK their GM applications are the only ones that come with the replacement spring in the kit.
 
#23 ·
I can't remember ever getting anything but just two shocks in our kits that we sell, but we sell the 504-123 most of the time, since when you factor in the extra labor required to make the others work it's basically a wash and you might as well get the OEM fitment in that case

if i recall correctly our 504-547 kits don't come with that gabriel air line kit (we've had to order it separately) but maybe that has changed - it's probably been a year since we've done one of those kits
 
#26 ·
That is the one hundred thousand dollar question!!! Had the Gabriels had the slip on OE connectors on it, I probably would have went that route. My only guess is that they probably went threaded to fit a wider application of vehicles.

It never surprises me how so many parts are interchangeable among vehicles from not only the same maker but different makers as well, but sell to us consumers unknowingly, and in many cases, the parts are listed as a higher price depending upon vehicle!


Dayum parts people!!!!!:hmm: (Just messing with you Chris :poke:)
 
#27 ·
I would guess that the clip-on OEM style air line connector is patented or something and GM won't let them use it (or use it for cheap).

What really gets me is why ACDelco can't use it since their 'selldown'/'additional usage' part is the same as the Gabriel - but maybe that's just pricing again.
 
#28 · (Edited)
I would guess that the clip-on OEM style air line connector is patented or something and GM won't let them use it (or use it for cheap).
The Monroe MA822s have the clip-on OEM style airline connector, and they cost less than the Gabriel Hi Jackers. I probably would've gone that way but I hear the Gabriel struts are smoother than the Monroes, so I took that route in order to match the front (currently OEM, next Gabriel Ultras) to the back.
 
#30 ·
I would've done the same as you, but I wanted to get OE, so I went with AC Delco (which happened to be a Gabriel Hi Jacker in disguise). I then noticed one of my lines was damaged, and since the OE lines are $$ to replace, I patched it with a Gabriel kit. Meanwhile, Monroe NEVER replied to ANY e-mails sent through their customer support form on their website. So I ordered Gabriels and they should arrive today, returning the ACDs as defective, because they don't fill up with air (the chambers are larger and require more air than the OE). This lack of air, causes the shocks to be very firm and very noisy (sounds like someone is knocking on the trunk). Gabriels come with a spring to be replaced inside the dryer, which I will replace and that will cause more air to be in the system, filling up the air bag inside the shock).
 
#32 ·
This is timely information, however, to throw a wrench in the works, the AC Delco
book quotes ABSORBER KIT,RR LVLG SHK DUAL PKG
Part Number: 504-97
Product Notes:
[Rear Levelling Shock Absorber Kit(VPI 1-877-846-8243)]; Hearse Conversion (B9Q) ; Limo pkg (V4U) ; Hvy Duty Susp (FE7) ; Except; Armored body equipment (B05)

Per Vehicle: 2; Years: 2000-2000

for my application.... Its 6'' stretch ( 8 bolt rim) similar to the DES of previous years...
Can the MA822 be used here, as Monroe indicates, too....?

Thanks in advance
 
#37 ·
ok, just making sure

the other option is the FE7 suspension option... it seems as though you may have that

i can't get that 504-97 acdelco number to come up anywhere... (VPI means it's been discontinued and you have to buy them from VPI instead of GM)
but the MA822 is the same as acdelco 504-547 GM#88946635 - which has been one of the parts discussed extensively in this thread

i would guess that you're not going to be able to use the MA822 and that the 504-97 is different (although it might work)

i can sell the OEMs with limo pkg (V4U) & without up-armor pkg (B05)
88964541 & 88964542 $158 each (list price is $216 each)
if you do have the B05 up-armor pkg then they will cost about $100 more each
 
#38 · (Edited)
ok, just making sure

the other option is the FE7 suspension option... it seems as though you may have that

i can't get that 504-97 acdelco number to come up anywhere... (VPI means it's been discontinued and you have to buy them from VPI instead of GM)
but the MA822 is the same as acdelco 504-547 GM#88946635 - which has been one of the parts discussed extensively in this thread

i would guess that you're not going to be able to use the MA822 and that the 504-97 is different (although it might work)

i can sell the OEMs with limo pkg (V4U) & without up-armor pkg (B05)
88964541 & 88964542 $158 each (list price is $216 each)
if you do have the B05 up-armor pkg then they will cost about $100 more each
Thanks for this info.. Would you mail to Canada when I need them...?

Monroe mentions the 822. The car has load levellers, with no electronics.
I ll see if theres any sign of a part number left on them when its up on the hoist monday..

Thanks again

I Suppose you could check by vin?
 
#39 ·
i did not use a VIN... that would be a good idea though - just to make sure

shipping to Canada gets complex - we use UPS and they have their own customs broker so we 'can' ship to Canada, it just gets a bit more expensive
you can arrange for shipping and email me a shipping label - that's another option
 
#42 ·
Re checking with Monroe, I was sure the MA822 was specified, but seems to be excluded for Limo or Armoured now..

Rock Auto is a neat site.. thanks...
but Im lost now.. eliminating the Monroe and AC equivalent, Im reading
''
ACDELCO Part # 504123 {#19177314, 19207418, 22064810, 504109, 50496} WHEN REPLACING 19207418 W/OEM ABS, DON'T ORDER T/W 19210500; Alip-On Air Line, Pair
ABSORBER,RR LVLG SHK WHEN REPLACING PART NUMBER 19207418 WITH AN OEM ABSORBER DON'T ORDER PN 19207418 T/W KIT PN 19210500. THE KIT IS NOT REQUIRED; w/SOFT RIDE SUSP(FE1); CODE:RE,XF
ABSORBER,RR LVLG SHK WHEN REPLACING PART NUMBER 19207418 WITH AN OEM ABSORBER DON'T ORDER PN 19207418 T/W KIT PN 19210500. THE KIT IS NOT REQUIRED; w/SOFT RIDE SUSP(FE1); CODE:BD,W2'

Is the a chart that x references AC Delco and GM part #'s??

UPS is very punitive to import as they charge obscene brokerage rates to collect
the dreaded Canadian HST on parcels being imported.. even under free trade..

ps
Whats a reasonable price for new CV half shafts...?

Greg
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top