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Z66 Shock absorber part numbers.

I think this is what you're after for your 2004
I know I said I'd like to keep it stock but I'd prefer to best performance over stock. Looks like Bilsteins are on it now. Not sure if they came with the truck new or were replacements. I've owned it for only a month. When I bought her she had only 78,000 miles on it. So they could be original equipmen??!!
 
At one time a Z66 suspension was considered more of a on road smooth riding/load leveling suspension good for highway use and towing. Not sure what company made the Z66 shocks though. I do know back in 2004 and other years the AV in the Z71 package used Bilstein shocks to improve performance while off roading. I test drove most models of AVs and my personal opinion is that the Z71 shock and spring setup feels more like a "sport suspension" package and was not as mushy feeling as the stock suspension. It is not harsh on the highway though and I bought a 2004 Z71 in 2004 and again in 2008.
 
I think this is what you're after for your 2004
Bain Man. When I go to the GM Parts Direct web site and enter my VIN it gives me a front shock with part number 15210859 but under description it clearly states OFF ROAD. The number you gave me, 89038595 clearly states SMOOTH RIDE. So I am going to go with the Bain Man cause it seems you are correct. Thanks again!!
 
Hello Vaeagleav and thank you for the info. Anything and everything helps at this point since I am seriously ignorant about this Avalanche but getting educated hourly. I bought, brand new a 04 AV 4x4 in 04. I didn't get around to getting to know her that well. Nasty divorce forced it out of my life but I swore i'd get another, A bucket list thing. I'm retired now and couldnt pass this one up. 04 Z66 in white, like my last one, leather, all the options that I don't need, like folding mirrors and heated seats and it had only 78k miles. Some rust cause it spent most of it life in New Jersey but in overall dam good condition for a 16 year old AV. Now im trying to learn everything, RPO codes etc because I want to put the best parts into this AV. I plan on taking her to Valhalla when its time to go. LOL. From reading lots of posts I beleive that the stock shocks are in fact Bilsteins. In fact the shock on it now are blue on the top stage. Cant tell if its yellow on the bottom tho. Too much rust.
 
I'm back to confused after the resonse from Vaeagleav. Is the OFF ROAD shock that comes up under my VIN on GM Parts direct the true Z66 shock and the SMOOTH RIDE is actually the stock shock for non Z Avalanches? Dont know but I want to get this right for me and for other members in the future. So I sent a question? email to GM Parts direct. I'll let you know what they say
 
I'm back to confused after the resonse from Vaeagleav. Is the OFF ROAD shock that comes up under my VIN on GM Parts direct the true Z66 shock and the SMOOTH RIDE is actually the stock shock for non Z Avalanches? Dont know but I want to get this right for me and for other members in the future. So I sent a question? email to GM Parts direct. I'll let you know what they say

Z66 = on road
z71 = off road

.

excerpt from link above: Premium Smooth Ride: indicated by the RPO code ZW7. This suspension uses a conventional suspension in the front, but the rear uses a self-contained, self-leveling Nivomat shock in the rear. ZW7 equipped trucks come with a softer spring in the rear since the Nivomat self-leveling system does some of the work of holding the truck up. Replacing a ZW7 Nivomat unit with a standard shock requires also replacing the spring, otherwise the truck will sag in the rear and have a much harsher ride and potentially dangerous handling.

You want the smooth ride shock if you have zw7 RPO.
 
Well guess the writing is on the garage floor so to speak.

I see hydraulic oil spots under the rear of the avy near tire... bottom of shock felt wet and oily....

will crawl under to confirm but it is not fuel or brake fluid and well nothing else back there...

so my stock shocks made it to be 19 years old and then they spit up their guts.

Anyone find these NIVOMAT shocks cheap?

Part Numbers I found:
GM = 15756926
ACDELCO = 54078
Sachs = 030-239
KYB = SR2003

Are those correct?
anyone know any other PN that feature the self leveling pump me up thingy?

Anyone find them for under $250?
Rock auto seems to be OK pricing
 
Finally Purchased KYB 2003 SR shocks today.
ROCK AUTO baby
They were the cheapest delivered by good margin even after shipping and tax.
Just under $560 for the pair at my door.
Which saved me Over $100 from other stores and brands.

I probably spent and hour shopping for SACHS, DELCO and KYB.

Hope they go on easy enough as I am getting seasick when I drive avy bouncing down the road....
 
Done. took about 90 mins using floor jack and jack stands no air tool as my impact seems to be a Dead as it has no torque.

On one side at a time
Jack frame up and support on frame with stand.
Remove tire
Remove 3 small 7mm screws holding plastic in fenderwell rear... bend this piece and lay it forward.
Remove upper and lower shock nuts from shock bolts - need back up wrench I used 13/16".
Put floor jack under lower shock mount - and jack a bit and the top bolt is easily hammered out.
Shock falls rearward a bit and lays against e-brake cable - no biggie.
Remove lower bolt by hand
Remove and replace shock.
Put back together installing lower bolt first
Use jack to raise axle up until upper bolt lines up and install it.
Tighten nuts and well put the other stuff back on

Repeat other side.
Test drive... wow no more bouncy...

Old shock one was complete crap as I could collapse it and it stayed.
The other would collapse but would slowly creep back to extend.

PS you cannot manual compress these shocks by hand and they come in full extend position.

Hope this helps.
No pics as well did not think of it as it is simple job.
 
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