Intro-05 Denali Yukon shocks

[Zayzay]

(Apologies in advance as I’m pretty new to all this) Hi all, I just bought my 2006 Denali Yukon recently and had some questions about the suspension. It does have the RPO code Z55 for the auto ride. However, at some point someone replaced the shocks with KYB gas-a-just shocks and they’re now in need of replacing. Reading through the forum I see that it’s necessary to also replace the springs if you’re going to get rid of the auto ride. My question is, how do I confirm that the previous owner replaced the springs or would one assume they’d have done them both? As well as any recommendations on a new set of shocks? Thank you all in advance for any insight you provide!

 

[Fless]

I assume you're talking about only the rear shocks. (?)

Don't confuse Z55 with the Premium Smooth Ride suspension (codes ZW7/G65). When those rear G65 self-leveling shocks are changed to conventional shocks, the springs should also be changed to a stiffer spring.

Now, I'm not familiar with the OE Z55 components and what modifications need to be done if the rear shocks are changed, but someone else on here likely will, and will chime in.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

If the truck has the Z55 RPO code, then the rear springs are specific to that active Electronic suspension, and they are softer than an equivalent passive suspension. If you go from an active Z55 suspension to a passive suspension, you need to replace the rear springs with a non-Z55 suspension specification, and those springs will be stronger/stiffer (because that do not have the aid/assist/support of the air bladders built into the Z55 shock).

I have found that the springs have a part number sticker on them, and that sticker remains readable for many years. Check out the existing springs to see if the part number sticker is still readable. If yes, then you will know if the springs are Z55 compatible or not.

 

[Zayzay]

Added a few photos, little rusty but have plans to fix that or atleast stop it the best I can! I also included the RPO codes and a picture of the spring, I couldn’t see any part number stickers on it what so ever.

 

[Joseph Garcia]

Looking at the springs, I'd say that they are not original springs, and there is no corrosion and/or accumulated road dust on them, and for a GMT800 truck and its age, there should be. As such, I don't know of any way to determine their specs.

 

[mountie]

Added a few photos, little rusty but have plans to fix that or atleast stop it the best I can! I also included the RPO codes and a picture of the spring, I couldn’t see any part number stickers on it what so ever.
View attachment 435954

Your RPO shows the "G65" which shows, your original shocks are an adjusting - height, setup.
Your local GM dealer will tell you what is specific for your Denali Z55 suspension, showing your VIN number.
BTW...... Your springs "look" pretty much newer than an original spring would look like by now??
Original factory springs usually have a sticker wrapped on the lower spring, and usually survives the age, to still be readable.
This forum could correct me, but, a Z55, or ( as in my Yukon), has the ZW7 ride..... But there are more than one version of the Z55 ? There are 3 versions of my ZW7 Premium Smooth Ride, depending on the additional, ( no additional ), RPO code, to go with it.
DON'T trust a 'shock absorber' seller...... Their info is NOT reliable !!

 

[Zayzay]

I assumed the same considering how good the springs look for a Minnesota truck. I imagine the previous owner did new springs when he did the KYB shocks. I just wanted other input to make sure i wasn't making a mistake by not ordering springs as well. Thank you guys!
I am thinking about ordering the same KYB gas-a-just shocks that are currently in it for all 4. Or do you have any other recommendations? I considered the Bilstein 4600 but they're $150 more for a set of 4

 

[Zayzay]

On a different note, I'm also considering doing front and back sway bar end links and front tie rods . However, looking on Rock Auto, the front sway bar links vary in bolt size from 8" to 10" as well as different sleeve sizes. Can you help me understand why that is and what it is that i should order for both links and tie rods?

 

[mountie]

To add...... As you describe, " Shocks need replacing".......
I can guess...... Those coil springs are too soft, as if the replaced coil springs may have been ALSO too soft. Your G65 code requires a soft coil spring, because, the original correct factory shock supports a lot of the weight. My guess is, since your concern that you "need new shocks", the springs are still too soft, feeling your worn shocks....
My "non- adjusting" shocks had 175,000 miles on them, but I did not find any issues. And my springs are a tad firmer..... I replaced my shocks due to age, only.

 

[mountie]

On a different note, I'm also considering doing front and back sway bar end links and front tie rods . However, looking on Rock Auto, the front sway bar links vary in bolt size from 8" to 10" as well as different sleeve sizes. Can you help me understand why that is and what it is that i should order for both links and tie rods?

Hellwig front / rear swaybars. I replace both.... I LOVE them!! Factory swaybars are a hollow pipe...... Hellwigs are a stout solid chrome molly, and all new hardware.

Get a flashlight.... go underneath, look at the ends of your rear swaybar..... Notice the ends are "crimped flat"... Hollow tube..... crap stuff....

 

[Zayzay]

That makes sense if the springs are to soft still, i didn't even consider that possibility. I need to head back to the drawing board and find out more about firmer springs i can put in.
and thank you for the recommendation, it might be a little out of the budget currently but hopefully i could do the entire kit down the road.

 

[mountie]

That makes sense if the springs are to soft still, i didn't even consider that possibility. I need to head back to the drawing board and find out more about firmer springs i can put in.
and thank you for the recommendation!

VIN number..... GM dealer..... they'll show you what was supposed to be under your Denali. That will guide you in your search.

 

[Zayzay]

Thank you for your assistance

 

[mountie]

Thank you for your assistance

I don't know, if you can find the coil spring rate, on your current set up..... I don't know if even GM can tell you the spring rate on the springs your Denali came with.....
( Maybe the diameter of the coil ?? )

 

[Fless]

Your RPO shows the "G65" which shows, your original shocks are an adjusting - height, setup.

NOT TRUE. G69 is shown, but not G65.

Show me the G65 on this sticker:

 

[mountie]

NOT TRUE. G69 is shown, but not G65.

Show me the G65 on this sticker:

View attachment 435966

Let me put on my reading glasses......... Oh, ...yea......

 

[SilverSport]

if your Denali already has KYB Gas-adjust shocks those rear springs may already have been changed from OEM

Bill

 

[petethepug]

Try and find the harness that used to connect to the shocks connector. More than likely it has fun size resistors taped into them. If the front shocks still have the harness connected to the top the past owner may have kept the z55 intact.

 

[pwol1962]

I just replaced the front and rear shocks on my 118,000-mile 2003 Suburban which had the costly ZW7 auto autoride shocks. I ordered the AC Delco rear shocks for about $41 each from Rock Auto. Shock extension and compression and the ride height is the same as the ZW7 shocks. Ride and handling are excellent. Saved a lot of money. Total cost was less than $150 which included shipping from two locations
The rears are difficult to remove the top mounting bolts and require removal of the inner fender lining to gain access to the top bolts. The liners were easy to remove and replace. Accessibility to the top bolts was still challenging. Spent 2 hours R&R the rear shocks and 1 hr 15 minutes to R&R the front shocks. You won't be disappointed.

Let me know if you need the part nos and exact prices for the front and rear shocks. The front shocks were for auto ride and cost was around $31 each.