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Discussion Starter #1 (Edited)
Hello all, This project was super fun for me because it involved wiring , sleuthing & lil parts hunting at local junkyards/online to make this write-up cut free and fully able to return to stock. Plus I was able to choose any strut/spring combo I wanted and possibly help get some ill handling GMT900s safer. Since there is no info out there really I had to err on the side of caution with resistor wattage ratings,I address this in parts list. It is possible to A) Delete front and keep stock rear full magnetic w/ air leveling or B) Delete both ends MRC and keep rear air leveling with cheaper Z55 gas/air leveling conversion shock or C)Delete both ends MRC,disable air compressor somehow and run regular gas shocks on all corners.

I chose 'B' because I occasionally have a full load with 6 passengers and my sub box (80lbs) is behind my 3rd row...FYI on C I'm not sure if you can disable the compressor by pulling fuse and not trigger suspension warning. Im sure some will want MRC & air gone. I can do a lil help if people chose that option.


Parts
(2) https://bit.ly/2KDxq7K [pigtail harness for front] Can be had for free at junkyard, used on front ABS wheel bearings of GM FWD cars and on top of engine FWD V6 GM cars mid 80s-2008

(2) https://ebay.to/2KP20up [ 2 ohm 200 watt resistor for front MRC--this is overkill,I think a 150w would be fine with slight heat increase being penalty]

(2) https://bit.ly/2NxXVJM [pigtail harness for rear,not needed if doing a front conversion only,option "A']

(2) https://ebay.to/2MPVYqY [ 1.5 ohm 100 watt resistor for rear MRC, not need if doing Option 'A']

(2) New front struts and/or rear shocks depending on your option
https://bit.ly/2IWPxQx (front strut assembly,pick any you want this is what I used)
https://ebay.to/2zaE14e (Z55 gas/ air shocks, pick any you want..Arnott also offers this for a little more money)

optional parts
zip tie, wire loom, wire, ring connectors. heat shrink
https://ebay.to/2KyAEJL (rear spacer to give rake back, personal taste and might not be needed depending on what you chose for front)


I went with KYB SR4079 for my fronts since I wanted new springs,etc. The SR4079 were a lil tall & looked like I had installed a mild leveling kit so I installed Moog 81071 rear springs (which was a waste, rear stayed same height). Then I added 1" spacer to help lift rear to give rake back. Interesting RockAuto rear spring selection has ballooned from 4 to 10 choices and Im sure there is a spring in there that can give rear height without the spacer I used. FYI those who want to keep original MRC front spring and swap them over to a gas strut will need a new strut mount due to MRC strut shaft hole being a different size (just order 2 for Tahoe with no MRC or Z55)


Front

1)use front pigtail harness, ring terminals,wire loom to build a harness to interface with front of truck wiring, I used about 6' of stranded wire [make 2 of these,polarity is irrelevant]





2) Disconnect connector from top of strut and separate the adapter from the main wiring harness. (Place adapter in safe place for future if returning to stock P# 19180262 if you lose it $25 x 2)



adapter next to harness that will take its place from step 1


3) scout a suitable home for the front 2 ohm resistor, It can be hidden but be aware of salt,engine exhaust. Please excuse her dirtiness:suspense:


4) connect new harness to vehicle harness,resistor and route wires away from any moving part or exhaust & zip tie connectors together since they wont latch


5)Repeat on opposite side and install any strut of your choosing
 

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Discussion Starter #2 (Edited)
Rear

1)use rear pigtail harness,wire loom to build a harness to interface with rear of truck wiring, connection is soldered for max strength but spade can be used I also I used about 2' of stranded wire. [make 2 of these,polarity is irrelevant]


2) shave off lock tab with razor blade or dremel



3)unplug connector from rear strut and plug harness with resistor into stock wiring harness. use zip tie to firmly hold them together since they will not latch.


4)mount resistor on vehicle away from hot sources


5) Install any rear shock you want
[
 

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Thanks for this write up. Just ordered a 2/3-4" lowering kit from Norcal SS, and the rest of these parts. Going to try the Z55 air shocks on the back, but will swap to Fox if the ride isn't much improved. Using Fox Coilovers with Eibach springs in the front. I used a similar Fox setup on a 1500 Ram, and it rides like a dream.

Really hoping this improves ride quality. The 2017 Escalade rides like a 100k mile car with blown shocks.
 

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Hello all, This project was super fun for me because it involved wiring , sleuthing & lil parts hunting at local junkyards/online to make this write-up cut free and fully able to return to stock. Plus I was able to choose any strut/spring combo I wanted and possibly help get some ill handling GMT900s safer. Since there is no info out there really I had to err on the side of caution with resistor wattage ratings,I address this in parts list. It is possible to A) Delete front and keep stock rear full magnetic w/ air leveling or B) Delete both ends MRC and keep rear air leveling with cheaper Z55 gas/air leveling conversion shock or C)Delete both ends MRC,disable air compressor somehow and run regular gas shocks on all corners.

I chose 'B' because I occasionally have a full load with 6 passengers and my sub box (80lbs) is behind my 3rd row...FYI on C I'm not sure if you can disable the compressor by pulling fuse and not trigger suspension warning. Im sure some will want MRC & air gone. I can do a lil help if people chose that option.

[...]

I went with KYB SR4079 for my fronts since I wanted new springs,etc. The SR4079 were a lil tall & looked like I had installed a mild leveling kit so I installed Moog 81071 rear springs (which was a waste, rear stayed same height). Then I added 1" spacer to help lift rear to give rake back. Interesting RockAuto rear spring selection has ballooned from 4 to 10 choices and Im sure there is a spring in there that can give rear height without the spacer I used. FYI those who want to keep original MRC front spring and swap them over to a gas strut will need a new strut mount due to MRC strut shaft hole being a different size (just order 2 for Tahoe with no MRC or Z55)
Thanks for sharing. I know this is an old post but it is actually new to me and I do have some questions. First, a little bit of background. I have a 2017 Escalade ESV Luxury with the Z95 package and Magnetic Ride. I absolutely hate the way it rides and I'd like to switch to Fox coil-overs 985-02-018 in the front and AC Delco non-magnetic air shocks 540-1675 in the rear. The mechanical aspect is pretty simple and it's something I can handle myself within a couple of hours. I was researching online on how to go about the conversion and get rid of the Magneride without triggering the speed limiter and causing all kinds of warning lights when I found your post.

I understand that with the resistors the system is fooled into believing that the Magneride shocks are still present and that should work on my truck as well. However, I noticed that you did not address the issue of the ride height sensors for the front. My issue is that unless the replacement for the OEM suspension, in this case, the Fox coil-overs, is exactly at the same height, the Suspension Control Module (SCM) will be continuously sending current to the shocks thinking they need to be adjusted and, of course, that could easily result in a blown resistor. I am thinking the best bet is to use a couple more resistors to simulate the 'zero' ride height position of the vehicle for the front. Alternatively, a scan tool could be used to perform a Ride Height Sensor Trim Procedure or Trim Height Relearn but it would be back to square one if a shock or spring needs to be replaced. Also, I don't know of any cheap scan tool which could perform that procedure. If anyone knows of one, please let me know.

I don't know if you have experimented with the ride height or do you feel that because of the 200W resistor you don't even need to worry about that? If that's the case, don't you think there is a risk of damaging the SCM itself since it will be continuously correcting for that problem. As for the rear, I am not worried about the ride height since I will be going with option B using auto-leveling shocks and I want for the correct height to be reported to the system anyway. Cheers!
 

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Discussion Starter #5
However, I noticed that you did not address the issue of the ride height sensors for the front
Very great catch!!! I'm so happy this thread saw some eyes. Ok here is a little background, the 16 pics that were posted seems like its rushed. There are actually 121 pics over 3 weeks that I chose not to share in order to keep the thread clean. The pics range from why I chose the ohm & wattage all the way to the coil spring diameter differences with digital caliper and even some 1 week testing pics with the resistor hooked up and inside the cabin next to a unhooked resistor to measure temperature gains/differences after extended driving.

This setup is still on the truck 1.5 years after I wrote this without a single issue and + 25k miles. Though I might search for different rear shocks over the eBay rear this spring. So here we go.....



This pic is with MRC strust installed and DMM hooked up to it. Strut wire harness has been disconnected from truck so the 2.5ohm is coming only from the strut. The ohm load changes (tested with me bouncing on running board/lifting up with jack). The ride height sensor made no difference hooked up or not to this value during bounce test with key on/off.



The wattage was based on this test which took place over a week of daily driving with 1 front MRC unhooked,other side still hooked up & rear untouched and served two purposes. 1) How hot would these get and 2) would suspension light stay off. This pic was taken after a 1.5 hour drive on 4/30/18. Google has temp in Chicago at 80° that day & no suspension light. Also during testing I discovered the check susp light is immediately triggered if the BCM doesn't see the strut or the resistor. It takes 5 key on/key off drive cycles once fault is corrected to self turn off.

Not sure of the theory of the front SCM blowing the resistor just due to the fact the stock wiring is about 16ga. going to the MRC itself. There is no way it would support 15 amps of current (200w ÷ 13v). I believe the SCM is sending much smaller wattages which is what was seen in very low heat temps during my testing & is also why I felt 200 might of been overkill. But since they would live under the hood 200w would shed heat better than a 100w.



This was taking during a 2nd week of testing on May 8th,2018 temp was 82°. The KYB were installed at this point and this made me happy I went with overkill. The ambient temp is 137° which heat soaks the resistor to 138° The highest temp seen during controlled in cabin testing was 103° IIRC.
 

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Very great catch!!! I'm so happy this thread saw some eyes. Ok here is a little background, the 16 pics that were posted seems like its rushed. There are actually 121 pics over 3 weeks that I chose not to share in order to keep the thread clean. The pics range from why I chose the ohm & wattage all the way to the coil spring diameter differences with digital caliper and even some 1 week testing pics with the resistor hooked up and inside the cabin next to a unhooked resistor to measure temperature gains/differences after extended driving.

This setup is still on the truck 1.5 years after I wrote this without a single issue and + 25k miles. Though I might search for different rear shocks over the eBay rear this spring. So here we go.....

The wattage was based on this test which took place over a week of daily driving with 1 front MRC unhooked,other side still hooked up & rear untouched and served two purposes. 1) How hot would these get and 2) would suspension light stay off. This pic was taken after a 1.5 hour drive on 4/30/18. Google has temp in Chicago at 80° that day & no suspension light. Also during testing I discovered the check susp light is immediately triggered if the BCM doesn't see the strut or the resistor. It takes 5 key on/key off drive cycles once fault is corrected to self turn off.

Not sure of the theory of the front SCM blowing the resistor just due to the fact the stock wiring is about 16ga. going to the MRC itself. There is no way it would support 15 amps of current (200w ÷ 13v). I believe the SCM is sending much smaller wattages which is what was seen in very low heat temps during my testing & is also why I felt 200 might of been overkill. But since they would live under the hood 200w would shed heat better than a 100w.
...
Happy new year and thanks for sharing the additional details! You are right that 16 gauge would never support the 15 amps it would require to blow a 200W resistor. However, I was considering using a much smaller resistor which could easily be hidden in a very small corner of the truck. However, that would only be possible if the ride height is zeroed out. In addition to being more elegant, I think zeroing out the ride height would truly open the door to replacing the original suspension with virtually any suspension without overworking the MRC. Either way, you did a fantastic job and the solution you implemented is definitely solid. Again, thank you very much for sharing. When I have some time, I will be experimenting with the ride height and will report my findings. Cheers!
 

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Discussion Starter #7
Thank you for the compliment, If you do decide to use a smaller resistor please post here (as well as in the 2017 & up forum) to what size you used and hopefully get some temp readings. I was so tempted to black mine out because of how huge they are. Its one of the reasons if you noticed I moved from the 138° picture location to behind the fuse box where its under the fender lip. After awhile it didn't bother me (Im the only one who goes under my hood) so I left it alone.
 

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I just found this write up. Great information. I have a 2010 Escalade Platinum with the Z95. 82000. All 4 shocks are leaking and the rears are mostly non existent.
A few questions if you don't mind? I'm looking to do option B like you. Any reason this would be different for a 2010 like I have? I would probably go with a more budget strut assembly up front. If I was searching what would be the application for a non-mrc strut assembly? I'm guessing a 2010 Tahoe or Yukon would probably work. Also just confirming I need to use a rear shock for the Z55 suspension setup? Other than that I am using the same parts that you used. I live in Las Vegas where it gets to 115 degrees in the summer. Any thoughts on the resistors getting too hot in this climate? If there is any other details I am overlooking, feel free to tell me. Again thanks for the great info/pics/ and write up.
 

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Discussion Starter #9
  • I haven't done any digging to spot the differences between 09 & 10 but Im suspecting things will be exactly the same. One important note is there is a difference between AWD and RWD front struts. This could of been limited to the strut coil assemblies I was looking at but a quick email to KYB yielded their SR4079 had a different spring rate than the SR4080 RWD only intended struts. AWD users who used the 80s left negative reviews of front sitting low, etc. I went with KYB because it seemed they were they only manufacturer acknowledging the AWD front end was heavier. I also scored a rebate of $50 IIRC on RockAuto, they are $263/pair shipped. I also went with full assemblies because the MRC strut plate would not fit over a aftermarket strut shaft. This was confirmed with pics/digital caliper if want to see (Im a pic lover lol).
The Z55 rear gas/air conversion shock is the simplest way to keep the rear adjusting by air as intended with the OEM MRC. Be aware that Im not saying buy true Z55 (autoride?/air, someone correct me if thats wrong) shocks, those are incompatible with your Z95 suspension and cost $250 ea. The Z95 was left high and dry with no air/gas downgrade option but can use the Z55 downgrade with my mod.

Temps, here in Chicago area we see no temps of that magnitude but according to my testing. The higher heats I saw were from heat soak from the engine,not necessarily the resistor itself. Im still rocking the same resistors from June 18' when I did the mod...they haven't been touched, moved or even looked at. So 2 summers and half through 2nd Chicago winter.

Please feel free to ask anything you need, I recommend searching for a assembly for the front.
 

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I suspect the 9 and 10 are probably the same. Good info about AWD vs RWD. as I have a RWD. I'll look at the SR4080. I like KYB so makes sense to use a high quality shock as I don't want to do this every few years. I fully intend to go with a full strut/spring assembly.

I will buy Z55 rear gas/air shocks and do your mod. I understand the Z55 won't work in place of the MRC Z95 style shocks. My compressor is good, so I'm fine with that.
Are the rear shocks you bought off of ebay good quality or would you go with something else?

Good info on the heat. I think it will be fine.

Thanks again for all the work you put into this. I'm going order parts today.
 

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And I'm assuming that I don't need to use the pig tails. I can simply cut the wires at the sensors and and run each wire to either side of the resistor.
 

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No need to reply to the last 2 posts. Your part number is correct and complete. I did not look at it properly.....sorry.
I'm going to use the connectors. a much cleaner installation. Again thanks
 

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Discussion Starter #15
Are the rear shocks you bought off of ebay good quality or would you go with something else?
The eBay shocks are ok...just that ok lol. They are some what noisy when I have the volume of radio down. Its like I can hear a slight rattle. Not that they aren't bolted to truck firmly but more or less in the mechanics of the shock itself. As far as function, they still absorb rough roughs great and lift rear truck as commanded by ride height sensors.

As expected, the ride is a lil firmer than when I put on all new MRC on all corners 3 years prior. When the MRC is new..its untouchable, I just felt cheated when I only got 3 years/40K mi for $1200 before fronts became overly stiff and thats what prompted this mod. Thanks again for the compliments, Im glad you decided against cutting wires (though its not a sin). I like to keep my options open on returning to stock lol
 

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Compared to how it is now anything will be an improvement.
Ordered all parts today. only difference is SR4080 instead of 4079. I'll give a report once i install everything.
 

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I would be interested in knowing more for option C on the rear i swapped shocks with belltech shocks and currently on a 3.5/5 drop no plans on ever going stock
 
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