Did GMC Install Basic Bilstein Coil Over Shocks in Envoys?

mrrsm

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A Suspension Question for Envoy Owners…

Did the Envoys or TBSS SUVs come with Bilstein Coil Over Shocks ...direct from the Factory?

The reason I’m asking is that I recently bought a Pair of of Envoy Coil-Over- Shocks that seem to be in fairly decent shape... just so I could “Monkee” around using a New Hydraulic Suspension Coil Compressor Tool Set Up.

I want to design and build a kind of secondary "Safety Cage" using an Idea that I've been ruminating over to handle some of the Serious Safety Issues and concerns recently voiced by a few other concerned Members about its use.

The eBay Salvage Yard Merchant wanted close to $100.00 a PIECE for these. But after I put in a low bid at $40.00 on one and $45.00 for the other...I won BOTH Auctions. So to me, they look Pretty Damned Good right now...(But what do I Know… Right?). These actually look good enough just the way they are to get bolted right in, but I STILL want to use them as Guinea Pigs in my Test.

The thing of it is ...I spied the Bilstein Labels on the lower Hydraulic Cylinders and the apparent Part # C004. So now I’m curious whether or not GMC sub-contracted with Bilstein for a Non-ACDelco Pair of Coils over the Bilstein Tubes … JUST for the Envoys or TBSS flavors of our SUVs. Here are some images of these things. Methinks these were taken off of an Envoy way out in the Arizona Desrt or perhaps from some other Bone Dry Western State, as they have Next To No Rust on them:
ENVOYCOILSNSHOCKS.jpgENVOYCOILSNSHOCKS2.jpgENVOYCOILSNSHOCKS3.jpgENVOYCOILSNSHOCKS4.jpgENVOYCOILSNSHOCKS5.jpgENVOYCOILSNSHOCKS6.jpgENVOYCOILSNSHOCKS7.jpgENVOYCOILSNSHOCKS8.jpgENVOYCOILSNSHOCKS12.jpg
 
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mrrsm

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I Think I JUST Found the Answer to my Question... Right Here:

h ttps://www.amazon.com/dp/B00BYNJAPS/ref=au_as_r?_encoding=UTF8&Make=Chevrolet%7C47&Model=Trailblazer%7C489&Year=2002%7C2002&ie=UTF8&newVehicle=1&vehicleId=1&vehicleType=automotive

BLACKOEMBILSTEINS.jpg

So... YES... The OEM Installed Shocks came as Bilsteins DID come from the GMC Assembly Line.

BLACKOEMBILSTEINS1.jpg

Based upon such Rave Reviews... During the intended "Test"... I might just get a Pair of THESE and Swap Out those Older OEM Black Bilsteins... (Sans also installing the Moog Upgraded Springs since my TB is a 'lightweiqht' 2 Wheel Driver...)
 

xavierny25

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Off topic: but if your interested in recouping some funds I'll gladly purchase the 2 shock tower knuckles if you won't be needing them. I've been looking for a decent set to have powder coated and those seem to be in really good shape.
 

mrrsm

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@xavierny25 ...if it were not for the fact that I would have to wander out from my isolation in our enclave to the Local Post Office or deal with either FedEx, UPS or USPO people Face To Face... I'd just send them up to you in NY. But right now...I have to err on the side of extreme caution because too many Floridians walk around carrying COVID at rates that threaten my life.

Look at the latest infection rate and death numbers... We are in bad shape in my county on the Gulf Coast with millions here and I feel like I'm under siege at 71 YOA and being Diabetic.

But... I'll make you a promise though. As soon as a viable, safe Anti-COVID Virus Vaccine becomes available and my wife and I can get our Shots... We'll re-visit this idea and in the mean time... I'll hang on to them for you. I promise.
 
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gmcman

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Dec 12, 2011
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I was under the impression that the Bilsteins were the OEM shocks across the board and that's why everyone recommended them as replacements.

The Bilsteins were OE, but not as firm as the HD line. I wish they had something in the middle of the two, but I do like the HD.
 
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mrrsm

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Jesus Palomino... Can You BELIEVE These People...?!

I tried to poke around and see what I could find on these 'Shock Towers they call Yokes'.... Christ Almighty ... They're just Two Pieces of Sand Cast Molded Pig Iron with Two Concave Holes Hogged Outs on their ends!

And MAYBE they had to Swipe them a time or two with a Hand-Held Grinding Wheel, just to knock off the Casting Sprue ...and perhaps less than minute to Shpritz em' down with a little Black Enamel Paint.

That's IT!

But My God...You'd think that these "Cast Iron Book Ends" were Made Out of "UnObTanium" for the amount they charge for the Damned Things!!! But...maybe they already know what I found out after searching around and NOT being able to locate other used Yokes ANYWHERE.

Fugggedddaboudit!

So... @xavierny25 ...When the time is right... I'll send these things to up there to you, Free of Charge (including The Postage Stamps)... 'cause THESE (&$*X#@/) Guys...Have MADE ME MAD!!!


https://www.gmpartsdirect.com/oem-parts/gm-yoke-15743860/?c=Zz1mcm9udC1zdXNwZW5zaW9uJnM9c3VzcGVuc2lvbi1jb21wb25lbnRzJmk9R04wMjE2ODUmcj1sYXllcl8xMCZhPWNoZXZyb2xldCZvPXRyYWlsYmxhemVyJnk9MjAwMiZ0PWxzJmU9NC0ybC1sNi1nYXM=

TB-ENVOYSUSPENSIONYOKE.jpg
http://rover.ebay.com/rover/1/711-5...0001&campid=5338077216&icep_item=401775608294

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http://oemcats.com/oem-parts/15743860.html
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xavierny25

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@MRRSM thats the reason I asked to buy them from you. I would of purchased them new and powder coated them, like I have other parts on the Envoy but with the price tag ranging over $100 a pop its not worth it. The ones you have there seem to be in relatively great shape.

Thanks for such grand an offer I simply can't pass up. There is absolutely no need for you to put yourself in harms way to have them shipped to me. So when things get substantially better in Fl. Like they have here in NY and your comfortable doing so let me know and I'll pm you my address and info.
 
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mrrsm

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Will Do, Brother... :ok:
 
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aaserv

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Dec 1, 2019
408
N of Baton Rouge, La.
Lets hear some good/easy methods for removing them and Ill retire selling yokes....lol I could be pulling several pair a month from the local yard just never thought of them as valuable.....but hell they sell for more than cats! However just yesterday I spent a good 45 mins to an hour getting 1 loose on the passenger side of my truck..... Not being a lefty I just couldnt find a good angle to hit from. I used my ball joint tool to wedge it and eventually got it off but there has to be a better way. Heating them would probably work since Id just be pulling the yokes and not concerned with melting the bushings in the control arms but hauling my Oxy/acyl rig into the Junk yard is not very appealing either.
Anybody know of a puller that would get behind this thing and be strong enough to pull it????
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
hauling my Oxy/acyl rig into the Junk yard is not very appealing either

And most yards don't allow them.

Same as ball joints and tie rods, just smacking them with a BFH usually does it. A ball joint pickle fork, as you used, is also an option but hasn't worked for me.

These yokes, AFAIK, aren't really in high demand since they are just a chunk of cast iron and most people don't look for pristine ones to powder coat. The only way to break one of these, I think, is to overspread the ears where the upper ball joint goes in and haven't heard of that happening.
 
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littleblazer

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Jul 6, 2014
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The Bilsteins were OE, but not as firm as the HD line. I wish they had something in the middle of the two, but I do like the HD.
I was told by a designer friend that the factory bilstein shocks on the TBSS are exactly in the middle of the regular bilsteins and the aftermarket HD. However finding a new set is difficult...
 
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mrrsm

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Using an Oxy-Acetylene Torch in close proximity to, or direct contact with any Cylinders filled with Highly Compressed Nitrogen and Flammable Hydraulic Fluid sounds a bit like "Famous Last Words...".

As per @Mooseman ‘s Experience… The Judicious Application of a BFH vs.“The Yokes” happens at 05:45 into this Video for their removal … and the Finer Aspects of the Installation of “The Yokes” back onto the Knob Ends of the Brand New Shock Tubes via another few well placed “Whacks” of the BFH happens at 10:54.

The Correct Orders of Operation Demands that the HAMMERING of "The Yokes" either On or Off, should ONLY be done BEFORE installing the Coil Spring Compressor Tool(s), regardless of the Type being used.

My guess is that in order to Protect the Ceramic Coating on the tidied up Yokes would demand using a small Chunk of 2” X 4” to prevent Chipping the stuff off from the very bottom of those Yoke Split Sections. A little swipe of Mobil 1 Grease on the Tube Ends would not hurt a bit either, as the installation of the New Retention Bolts and Nuts Hardware will finally cinch up the two gaps tight and offer no opportunity for them to accidentally slip off of the Two Shock-Struts:

I’m NOT an advocate of using any sort of those Screw-Bolt and Clasps Spring Compressors like the Young VOP (Video Original Poster) uses in this work, ostensibly under his Dad's Supervision.


...and in another similar Instructional Video, the VOP Demonstrates What NOT to Do in the Way that he Carelessly Handles the Compressing Coils with his Fingers in between them while also using an Impact Gun to tighten up the Two Coil Restraint Rods:


Once I assemble the New Hydraulic Shock Coil Compressor Device, I’ll take some images of its use after building a practical and worthwhile “cage” that can restrain the Compressed Coils under the worst of circumstances, should the Cast Iron Tilt-Angled Upper & Lower Coil Retention Brackets decide to Slip loose ...or Break.
 
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mrrsm

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While this Video dates back to the 1980's and 1990's Eras... The REP from the Bilstein Shock Absorber Company provides an EXCELLENT Visual Break Down of just exactly HOW their Brand of Shock Absorbers WORK... and WHY they are so designed right around the 3:00 time into this 6:00 Video:


Here is the Updated, Contemporary explanation, noting that little has changed since Bilstein first created this design:


The Cavitation Phenomena on display in both Vidoes showing the Loss of the Dampening Action required that it creates is something I never realized was happening within the Oil Channels and Chambers inside Low Pressure Liquid Controlled Shock Absorbers.

So this is definitive proof that GM has been using Bilstein Shocks on many of their Cars, Trucks and Van Series for over 40 Years, also benefiting the GMT360s too as OEM Installations.
 
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mrrsm

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Just stepping out of the shadows ...long enough to keep a promise I made to @xavierny25 about five months ago to send him a Pair of Cast Iron Trailblazer-Envoy Shock Strut Yokes… Free Of Charge. Please PM me if you still want these with your particulars and I’ll ship them to you gratis (Bubble Wrapped Twins) via UPS.

In the interim since December of 2020, I’ve taken the following steps to R&R them from their Envoy Coil Spring Assemblies and royally, loyally prepped them for you by following these procedures:

(1) Applied a 4 Lb Sledge Hammer (alternating front to back) to the outer, upper flanges of the Split Yoke area in order to knock them free from the rusted-on Shock Tube ends.

(2) Mounted them in a Large Vise and carefully wire-wheeled them top to bottom; inside and out to remove surface rust, scale and OEM Black Paint.

(3) Washed and Scrubbed any remaining surface residue with wire brushes and then placed each Yoke into Industrial Grade 2 Lb Plastic Zip Lok Bags filled with Evapo-Rust Gel. Left soaking for a week.

(4) Removed the Yokes and hand-washed off the Yellow-Green Evapo-Rust Goo under Hot Running Water while using Brillo Pads, Wire Brushes and dislodged all black carbon by-products from their surfaces.

(5) Obtained the Large Bottles of POR-15 “Marine Clean” and “Metal Treatment” and after a thorough De-Greasing Wash and scrub of all surfaces using Basting Brushes… Hand Dried each one.

(6) Set up a Rectangular low profile Pyrex Glass Dish and after laying down several Micro-Fiber Cloths (to prevent cracking the dish via dropped yokes) I immediately applied the “Metal Treatment” using cut down Basting Brushes and continuously lathered on the Zinc-Phosphoric Acid Treatment non-stop for 30 minutes all over the surfaces of the Yokes..

(7) Subsequently, the Cast Iron Yokes presented with a dull finish having a golden patina all over both pieces and so the job of preparing them for either a POR-15 Painting of Powder Coating was complete.

(8) When you open their Packing...they will be Bone Dry with no Oil or WD-40 coating them. Just give them a splash of Aqua Velva (Acetone would be better) and they’ll be ready to Powder Coat. :>)

For anyone else considering using this method, the basis for doing so in BOTH cases of either painting Cast Iron and Steel AND Powder Coating… this is an excellent explanation of why having a Zinc-Phosphate as a “Go Between” will serve well and truly to keep the Paint & Powder Coatings On The Metal.

https://productionpaint.com/why-zinc-phosphate-pretreatment-is-superior-to-iron-phosphate/

PS… Very sorry about this delay…Xav... but we’ve been on House Lock Down since January of this year and only just now got the chance to get our Moderna Shots (1st & 2nd). We've been waiting here three weeks for the Covid-19 multi-variant immunity to build up.



Back into The Shadows...
 

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xavierny25

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Mar 16, 2014
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Wow!!!! Thanks @MRRSM. I truly appreciate this. You went above and beyond to get those yokes cleaned up and ready to go in the booth. Please allow me to reimburse you for all the materials you used and shipping.

I'm glad to so you back around hope the family is still continuing to stay in good health and safe. I'll shoot you a pm shortly while I'm on break.
 
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mrrsm

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No Problem, Brother... I insist that you accept these components and just know that it was fun to make them ready for use again. I'll be shipping them out via UPS tomorrow morning, Monday, May 10th, 2021and then I'll PM you with the Tracking Number afterwards

(Nobody loves Giving the Gifts... as much as Santa Claus...)

Just want to offer a sincere "Thank You" to all those GMT Nation Members who PM'd me with your genuine concerns about my welfare. We are Okay here now and surviving while trying to avoid taking "The Final Dirt Nap" for as long as we possibly can. :>)
 

mrrsm

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Look for the "Dog Bones" to arrive around Wednesday, as I shipped them this morning around 8:00 AM EST via UPS using Second Day Air.

It took UPS up until just a few minutes ago to allow them to be tracked online. PM sent to you with the Tracking Number and a Screen Print of their current site activity on the matter.

Good Luck with these things... and unless I missed reading it, perhaps you can do a Write Up sometime on how you go about Powder Coating your suspension components.
 

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