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Discussion Starter #1
I recently changed JUST the front struts on my 02 STS and did not realize the front struts had a plug in for electonic monitoring. The new struts I installed do not have the plug in like the originals. I am getting the pesky "speed limited to 90" message. I have seen other posts talking about tricking the computer/sensors. Can I do this while running the new struts I have up front and the oem rear suspension? Any help is much appreciated.
 

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Re: 2002 STS seville

:hmm: Not sure if you can do the bypass to half the system or not. Bass may know.

P.S.
I edited your title to be a bit more descriptive.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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What is the build date of your 2002 - driver's door sticker.

Before mid-January 2002 the system was the F45 CVRSS active type; after 01-15-02 it changed - ALL STS - to the new F55 MRC active type. (See my username banner)

Two VERY, Very, VERY different suspension systems, each with their own workarounds when you cheap out and go passive.

The trick is to insert a resistor in series with the old chassis wiring harness connector, but the type of system determines the value of the resistors used - and they're quite different, too.

Best to go passive on all 4 corners - a half-active suspension system would be half-assed in performance........ You MUST retain the rear ELC system.
 

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Discussion Starter #5
Thanks for the info! Would it be better to just buy the proper front struts? If so, what do those usually run in price? If I am hearing you correct, I need to make the system passive at all 4 corners with the setup I have now. I will check the build date you called out when I get home for sure and report back.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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If you can find the correct active struts and shocks for your car - and - again - the build date makes a BIG difference - you will pay from $2200 to over $3000 to replace all 4 corners, not including any maintenance for the rear shock ELC system.

Your entire vehicle stability system is also now dysfunctional - many sensors normally supply body attitude info to the BCM and PCM in order to control the active suspension during all modes of driving - stopped, slow, fast, aggressive. With substitute passive struts/shocks the system is dead.

ELC = Electronic Level Control - a control system which uses height sensors, a compressor, air lines, and shock bladders to adjust rear ride height in response to added weight in the trunk or rear seat. It is NOT "air ride".

https://www.cadillacforums.com/forums/cadillac-seville-cadillac-eldorado-forum/205754-acronyms.html

Note the two different suspension strut prices - learn your particular system intimately - continue to the shock pricing (hold your heart) -

https://www.rockauto.com/en/catalog/cadillac,2002,seville,4.6l+v8,1379932,suspension,strut,7584
 

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Master of the Dark Art of Diagnostics
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I recently changed JUST the front struts on my 02 STS.................................

Can I do this while running the new struts I have up front and the oem rear suspension?
Any help is much appreciated.

the best answer is MAYBE -
while not ideal - you CAN mix active and passive in the F45 system -
I would NOT RECOMMEND this in the F55 system -

STEP #1 - determine which system you have - F45 or F55 -
the resistors used to trick the computer are quite different between the two systems -

in either case - you have already replaced the struts - (just curious - what brand/model struts did you buy?)
replacing the rear shocks is cheap and easy - why not simply finish the job?
MONROE MA822 - $57 - for the pair - with free shipping -
https://www.amazon.com/gp/product/B000C55T7W/?ie=UTF8&me=ATVPDKIKX0DER

Would it be better to just buy the proper front struts?
that depends on how you drive -

if you like to drive "on the edge" - taking exit ramps at 90mph - YES -
the electronic struts and shocks make a big difference in handling -

if you don't "push the car to its limits on every turn" - NO -
you will never notice the difference - except for a slightly LESS harsh ride -

If so, what do those usually run in price?
F45 struts - IF you can even find them - are around $750+ EACH -
F55 struts are cheaper and easier to find - around $600 - EACH -

F45 shocks - IF you can find them - around $600 - EACH -
F55 shocks - around $400 each
 

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Discussion Starter #8
Much appreciated guys on all the info. I really just want to get the suspension to a spot where the vehicle can be sold. It sounds as though maybe it would be best to remove the electronic rear struts and go passive on the rears as well. Once I get home today I will check on the build date and update here. Next question, who wants to buy a 02 sts with 75k miles two owner? Lol Will get build date on here soon. Thanks again everyone!
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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I've owned my 2002.5 since 11/05 - lots of past fun and games - Not in the Cadillac market - new OR old, any model, now or in the future.

Your STS, with new struts/shocks that match (and if you go passive you need to tell a prospective buyer that the car is no longer a Seville Touring Sedan) might fetch $500 - $1500, with luck. A "2002" STS went out the dealer's door at close to $58,000, all fees included.
 

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Discussion Starter #10
Alright, checked out the build date on my 02 sts. It is listed as 06/02. What are my options? Replace the good electronic struts in the rear with passive? Or do you think it is feasible to run a mixed system?
 

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Discussion Starter #11
I hear you on that..I bought my o2 sts from the original owner..it has every option, including paint and wheel options...I have the original window sticker..He paid 65k for it..I cant lie, its a hell of a machine...the old man that had it before babied it...so the motor is still strong and pulls like a freight train...I bought it with 46k miles and it has 75k miles now...Other than this current suspension deal, the car is immaculate in and out.....hoping to hear back if my build date is available to run a "mixed" suspension system
 

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Discussion Starter #12
Hey Bass, build date is 06/02...so that is the F55 system? In which you stated you would not recommend running a mixed system. Should I buy passive rear struts then?
You had asked the brand of the fronts I bought, I beleive they were "Gabriel" or something to that affect and I ordered off Rock Auto. I suppose I could order a passive set for the rear, easy install then I would be matching on all 4 corners.
Then you guys could give me the walkthrough on tricking the system to get the speed limiter turned off.
I would like to get all the suspension in place, then take it in for an alignment.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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A build date of 06/02 is the last of the 2002 model year, so the car has the F55 Magnetic Ride Control system, just like the somewhat later Ferrari and Corvette. 2002.5 - 2003 STS was used as the GM prove-mule for the Lord/DELPHI automobile suspension system before it went worldwide.

Our "model year" ran from about July of 2001 to June of 2002. The 2003 MY began in July of 2002.

Yes, you need to return it to all-stock MRC or all-passive. I think you should have bought Monroe struts - basscatt will know.

Look at your RPO sticker under the spare tire cover. That gives the codes of what's built into THAT car - here's mine. Note the FE3 (sport springs) F55 (Magnetic Ride Control). My build date is 02/02 - F55 production began at line startup in 01-15-02 but there are apparently a very few F55 STS that were hand-assembled in late December 2001.
 

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Discussion Starter #14
Great info! So I will replace the rear with a passive unit. I see many options on www.rockauto.com what would be my best bet on there for passive rears? Once I have replaced the rears and am then passive at all 4 corners, then will I be able to "trick" the computer? I will check out that sticker today and see what all the codes are, I will snag a pic of it.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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For the 2002.5 and later F55 system -

Ohms is the electrical resistance of the piece; Watts is the power handling capability - power resistors in-circuit can get skin-scalding HOT.

The "trick" is to bypass each strut/shock chassis electrical pigtail with a 2 or 3 Ohm 5 Watt power resistor, either wirewound or metal film. This simulates the electrical load presented to the chassis control and stability systems by the original active suspension parts.

Just like bending a paper clip into a U and sticking it into a wall socket. Insulate/waterproof well, wire-tie the pigtail out of the way.

Look at www.partsexpress.com - or eBay.

https://www.parts-express.com/cat/resistors-potentiometers/75
 

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Discussion Starter #16
Perfect! That sounds pretty straight forward. Well, I will get some rear shocks ordered and installed. Then work on the resistor part. Greatly appreciate the info! I will let you know how it goes. From your experience, would it be worth it to list for sale my working electronic rear suspension? Not sure what else I would do with it lol
 

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Master of the Dark Art of Diagnostics
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I hear you on that..I bought my o2 sts from the original owner..it has every option, including paint and wheel options...I have the original window sticker..He paid 65k for it..I cant lie, its a hell of a machine...the old man that had it before babied it...so the motor is still strong and pulls like a freight train...I bought it with 46k miles and it has 75k miles now...Other than this current suspension deal, the car is immaculate in and out.....hoping to hear back if my build date is available to run a "mixed" suspension system
===========================
I have the original window sticker..He paid 65k for it.
I can't imagine what was added to this car to get the window sticker up to $65K -
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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"Babied" Northstars are usually finicky slugs - the engine was designed and born to RUN.

Used MRC shocks make great fish trap anchors. Keep them on the shelf.

He overpaid by ~11,000 dollars. Note that my car has most of the extra options ... multi-disc Bose, Crimson Pearl, sunroof (damnit), others.

Tax, title, and tags in your area must be awful. People's Socialist Republics of California or Connecticut ???

Read this - it applies to us ........ especially the "Occasional full throttle operation is good .....". One of our articles written by one of the Cadillac Northstar System Powertrain engineers. ("Northstar" is not only the engine - it's the whole powertrain system.)

https://www.cadillacforums.com/cadillac-tech.html

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Master of the Dark Art of Diagnostics
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Hey Bass, build date is 06/02...so that is the F55 system? In which you stated you would not recommend running a mixed system. Should I buy passive rear struts then?
You had asked the brand of the fronts I bought, I beleive they were "Gabriel" or something to that affect and I ordered off Rock Auto. I suppose I could order a passive set for the rear, easy install then I would be matching on all 4 corners.
Then you guys could give me the walkthrough on tricking the system to get the speed limiter turned off.
I would like to get all the suspension in place, then take it in for an alignment.
============================
build date is 06/02...so that is the F55 system?
YUP

Should I buy passive rear struts then?
your car doesn't have rear STRUTS - they are simple SHOCKS -
and YES - as I suggested above - MONROE MA822 -

Then you guys could give me the walkthrough on tricking the system to get the speed limiter turned off.
purchase 4- 2ohm 10 watt resistors -
bend the wires into a "U" -
stick the wires into the plug that used to go to the strut/shock -
wrap them up with electrical take - tuck them up and out to the way -

I would like to get all the suspension in place, then take it in for an alignment.
replacing rear shocks does not affect the alignment
 

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Discussion Starter #20
Thanks again guys for all the advice and help. I will purchase the monroes that bass called out. I will take a pic of the original window price sticker later today and post it. Its been awhile since I looked at it, so very possible I am remembering the wrong msrp.
 
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