I put ZR2 shocks on my Yukon - need advice

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Scored Silverado ZR2 takeoffs with around 300 miles on them for $500 on marketplace. Wanted to delete mag ride, and I measured things out and. It looked like they would fit. With some help they do. Granted I’ve only drove it in and out of the garage, and to fit them I had to take the upper control arms off and now need an alignment, but.. they were about 3” longer than the stocks and it felt awfully stiff the little bit I drove it.
I checked vehicle weights 2016 Yukon Denali vs the ZR2 and weights and weight distribution is fairly similar so I thought it would be fine. Yukon weighs around 3,000lbs in the front, doubt the ZR2 is more, not by much anyway. I know the new generation has a different control arm geometry though, idk if that is what making these feel stiff on the Yukon. I measured a ZR2 shock installed on a ZR2 and installed it was maybe 1”-2” different vs the stock Yukons shock length installed.

I also had a 2.5” spacer in the front before the ZR2 shocks, obviously that’s gone now.

One of my thoughts is this: Would 2-3” drop lower control arm help the geometry perhaps and loosen up the shock abit? Now it’s pretty extended, hardly dropped at all when lowering the front end down after install.

Any feedback is appreciated!

Full vehicle pic is just with the spacers, and it has 18” AT4 wheels and 275/70/R18 K02’s

 

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Screenshot of it installed.

 

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Oh, and I bought some resistors and used the stock plugs off the old magneride shocks to wire them up, worked good, no suspension lights on the dash.

 

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Took some pics this morning, it’s pretty much maxing out the upper control arms travel, I don’t understand why the suspension is not compressing hardly at all…

 

[Silverado4x4]

My advice to you is remove it till you get the proper install parts everything in that front is beyond operating limits, your ball joints, CV axles, tie rods are way over operating angles and will fail iam not kidding with you I have seen where people did what you have done and the front wheels completely came off due to part failure.

 

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@Silverado4x4, perhaps I should have been more clear, I’m not driving around like this currently.

I’m trying to get advice on what parts I need or what I should do to make this work.

I was expecting about 2” of compression on the shocks once they were loaded with the Yukon on the ground and I only got 1/2”. I feel like if I got the expected 2” it may have been fine.

Any opinions on installing 2”-3” drop lower control arms, thoughts on if that could remedy this?

 

[stab6902]

Drop lower control arms would get your ride height where it needs to be, but it wouldn't change the wheel rate of the suspension; i.e. it wouldn't make the struts compress more with the truck on the ground. Based on your comments, your truck would likely still be way too stiff in the front, and ride poorly due to lack of available extension travel.

My best guess is that the geometry/motion ratio of the T1XX lower control arms is substantially different from the previous generation. I will do some math (hopefully I have some time tomorrow) and come back to you with a recommendation.

I am motivated to help you get this sorted out since I have the same shocks and also want to put them on a K2XX truck.

 

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Drop lower control arms would get your ride height where it needs to be, but it wouldn't change the wheel rate of the suspension; i.e. it wouldn't make the struts compress more with the truck on the ground. Based on your comments, your truck would likely still be way too stiff in the front, and ride poorly due to lack of available extension travel.

My best guess is that the geometry/motion ratio of the T1XX lower control arms is substantially different from the previous generation. I will do some math (hopefully I have some time tomorrow) and come back to you with a recommendation.

I am motivated to help you get this sorted out since I have the same shocks and also want to put them on a K2XX truck.

Thank you! I straightened the alignment a little tonight and got some bolts tightened on the lower arm so I could drive it a little. I just drove slow and tried to hit bumps, boy is it stiff and bouncy! I drove the front up on a curb and let it drop down off it and got a little travel but my guess is probably no more than an inch if that. They also did not settle lower after the drive. I’m 42” from ground to top of fender well. I measured a ZR2 today and the lower arms are about 1-2” longer, and the bottom mount is I think around an inch further from the frame. The ZR2 tires stick out about 1” further vs the Yukon.

 

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I’m sorry, about 2” further out vs the Yukon.

 

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@stab6902, I am curious about your first comment, about the lowering arms not helping the suspension compress… if the lower arm was 2” more level would it not be easier to compress the shock vs if they are at a steep angle like now?

Also I’m wondering if the lowering lower control arms move the lower shock mount position further towards the wheel/tire, which if it did I would imagine that would also help with having more leverage to compress the shock, no?