Zr2 front suspension

Joe97281 · December 15, 2023

I am going to order the front skid anyway. The stock setup is a plastic splash shield with metal engine plate. The Zr2 is aluminum one piece.

The Specs tab of the gmparts website matches the dimensions of the plastic + steel on normal trucks. Before there was alot of info out, I used a tape measure to verify the dimensions because there was no pictures.

I trust it will fit without anyone else confirming because the front splash shield has been the same for a long time.

ZR2 transfer case skid arrived today, and it is probably twice as thick as the standard. It will need 2 holes drilled in the crossmember, and at least one additional bolt.

Epsilon Plus · December 15, 2023

Thanks to Joe & newdude. Just ordered the whole kit and cabuttle for $1,278.01 shipped from GM Parts Direct. The knuckles were added to cart and in processing, so we'll see if it goes through or they kick it back, I'll update.

Had to split up the order though. Once I went over a certain item threshold (9,10) the shipping went from 120 to like 480 as if it's weight based or something I dunno. Still spent like $196 in shipping though so that hurts. Also hurts to spend more on a (likely) plastic diff drop bracket than a UCA lol. I even bought the jounce spacers for more than they should cost because I'm after a full factory style 2" lift. Only thing I didn't get is the DSSVs. Maybe one day when I'm crazy enough to spend $2,000 on shocks but I'd like to see some reliability or know they can be rebuilt before spending King Remote money. Just got a 3 month old leaking Bilstein 5100 warrantied and I'd hate to pay $500 for a DSSV for it to spring a leak no warranty.

If I can add all the skids I'll be doing that too so stay tuned for a full ZR2 suspension swap thread when I get to all of this one day. Right now I've still got some tread to burn on the stock tires before the GM Alaskan 18s and 35x11.50s go on. I'll wait to put all this ZR2 stuff on at that time.

Cheers.

Joe97281 · December 15, 2023

We look forward to seeing pics when the stuff arrives. Thanks for the GM parts direct mention, they were the cheapest, and have lowest shipping to my location.

I wouldn't worry about the "Diff drop" brackets, I think it is a full carrier support bracket with a deeper bend in it, therefore giving it a "drop". I'd love to know how much... the full 1.5 inches or something less?

I know some aftermarket diff drop pucks provide washers to lower the engine skid plate. That might make the one piece aluminum one have more value to you since we know it is intended to work with all the other parts.

It is the part I least excited about installing. Vid below for rough idea.

Epsilon Plus · December 15, 2023

Doesn't look fun. Although using an aftermarket spacer type would probably be easier, I'm all about the factory way of the ZR2 style.

Also, I got this:

"

This order is on hold awaiting your response.

Part number 85144996 is currently on back order from GM and it has been removed from your order. GM does not have an ETA for the part to be released off back-order.

Part number 85144997 is currently on back order from GM and it has been removed from your order. GM does not have an ETA for the part to be released off back-order."

Edited December 16, 2023 by Epsilon Plus

gemarsh · December 16, 2023

23 hours ago, Joe97281 said:

I am going to order the front skid anyway. The stock setup is a plastic splash shield with metal engine plate. The Zr2 is aluminum one piece.

The Specs tab of the gmparts website matches the dimensions of the plastic + steel on normal trucks. Before there was alot of info out, I used a tape measure to verify the dimensions because there was no pictures.

I trust it will fit without anyone else confirming because the front splash shield has been the same for a long time.

ZR2 transfer case skid arrived today, and it is probably twice as thick as the standard. It will need 2 holes drilled in the crossmember, and at least one additional bolt.

Do you have the part number for the front skid plate? I've read this thread 3 times and I don't see it listed.

Epsilon Plus · December 16, 2023

2 hours ago, gemarsh said:

Do you have the part number for the front skid plate? I've read this thread 3 times and I don't see it listed.

This is what I have so far. I'm gearing up for a full ZR2 conversion thread where we can put all the info in one spot.

gemarsh · December 16, 2023

Thank you.

215robert · December 17, 2023

Parts trickling in!

Epsilon Plus · December 18, 2023

22 hours ago, 215robert said:

Parts trickling in!

Is that bottom pic a skid? Which one?

215robert · December 18, 2023

Nope that's foot rest on my golf cart.

Epsilon Plus · December 19, 2023

1 hour ago, 215robert said:

Nope that's foot rest on my golf cart.

LOL! Was looking at pics on phone at work and kinda looked like a separate pic of maybe a transfer case skid.

Getting old!

215robert · December 19, 2023

Yes sir, I thought the same after you mentioned it!

Joe97281 · December 27, 2023

Measuring centerline to centerline of the holes in the shock, I get ~ 15 inch compressed and 18.75 extended.

3.75 inch of travel. That seems low. Rock Auto has specs for a lot of shocks, (https://www.rockauto.com/en/moreinfo.php?pk=14077621&cc=3450533&pt=7556&jsn=473). Even though the reference points for measuring is different, the extended - compressed for the stock shows 4.14 inch of travel.

Monroe replacments advertise 4.250 travel, and Rancho RS7 shows 4.41 in travel.

This makes me wonder if the Zr2 lower control arms have the shock mounts moved slightly inboard towards the centerline of the truck, or that the mount is taller.

Does anyone have a lower control arm not installed on the vehicle that they can take a picture of?

215robert · December 28, 2023

Received tracking this am on mine I will post when they arrive!

Joe97281 · December 28, 2023

Does anyone have a stock front shock they can measure?

I do not want to install the DSSV shocks on the front if they are going to get destroyed because I have not installed the zr2 lower control arms yet. My concern is the overall stroke length of the DSSV. I have read many times that the shocks on these trucks limit droop. An incorrect length shock would top out and limit travel, or the upper arm would hit the service stop. That would mean I cannot damage the shocks too badly in that direction (droop travel), but what happens at full compression? I assume that compression of the jounce bumpers take the force of suspension compression meaning the shock will never "bottom out."

I have the lowers, but the knuckles are on backorder. I am not going to change the arms until I can do uppers, lowers, and knuckles all at one.

I tried to spend some time figuring out what is different about the zr2 lowers. This is difficult since the stock ones are installed on the truck. My shoddy measurements show that the shock mounting hole on the zr2 arms is ~10mm higher than the stock ones. This makes sense if the engineers were trying to keep the original shock length as the 10mm would correct for the 1.5 in lift.

I do not currently have the space to jack up the truck or lower control arm to measure extended / compressed shock length with stock suspension components.

Measurements and insights are appreciated.