Confused about Z71 OEM ft. struts

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

dbell54

TYF Newbie
Joined
Nov 14, 2023
Posts
14
Reaction score
4
Allegedly my 2013 Z71 4x4 Tahoe has Rancho shocks and different springs in the ft. struts, but I can't find anything about replacement strut assemblies specific to the Z71. GM OEM lookup only shows individual parts. Depending on the source used, the shock for RPO 6TJ/7TJ is either 540624/20958798 or 540625/20958799. These are both the correct red color, so may be made by Rancho per OEM. But the only GM assy. I can find that supposedly is correct is AC Delco 903-600RS, which fits most 2013 Hoes. All other brands only have basically one option. No one mentions Z71. Rancho has the RS551784, which is for most. KYB has the SRM4079 Monomax which seems like it would be more appropriate for a Z71, but still isn't specific. Does anyone have any facts? I've spent the entire day researching without anything conclusive.
 

Big Mama

Full Access Member
Joined
Jul 21, 2015
Posts
3,090
Reaction score
1,802
Location
Virginia
@915_Tahoe may know the part number. He’ll need your VIN. Another option it to get the shock and have a local shop with a spring compressor swap in the new one.
 

915_Tahoe

Your GM Parts Specialist
Joined
Jul 1, 2018
Posts
1,333
Reaction score
1,853
Location
HELL PASO, TX
Allegedly my 2013 Z71 4x4 Tahoe has Rancho shocks and different springs in the ft. struts, but I can't find anything about replacement strut assemblies specific to the Z71. GM OEM lookup only shows individual parts. Depending on the source used, the shock for RPO 6TJ/7TJ is either 540624/20958798 or 540625/20958799. These are both the correct red color, so may be made by Rancho per OEM. But the only GM assy. I can find that supposedly is correct is AC Delco 903-600RS, which fits most 2013 Hoes. All other brands only have basically one option. No one mentions Z71. Rancho has the RS551784, which is for most. KYB has the SRM4079 Monomax which seems like it would be more appropriate for a Z71, but still isn't specific. Does anyone have any facts? I've spent the entire day researching without anything conclusive.
What's the last 8 of the VIN#
 

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
23,719
Reaction score
34,682
Location
Stockton, Ca.
Allegedly my 2013 Z71 4x4 Tahoe has Rancho shocks and different springs in the ft. struts, but I can't find anything about replacement strut assemblies specific to the Z71. GM OEM lookup only shows individual parts. Depending on the source used, the shock for RPO 6TJ/7TJ is either 540624/20958798 or 540625/20958799. These are both the correct red color, so may be made by Rancho per OEM. But the only GM assy. I can find that supposedly is correct is AC Delco 903-600RS, which fits most 2013 Hoes. All other brands only have basically one option. No one mentions Z71. Rancho has the RS551784, which is for most. KYB has the SRM4079 Monomax which seems like it would be more appropriate for a Z71, but still isn't specific. Does anyone have any facts? I've spent the entire day researching without anything conclusive.
throw those rancho's in the garbage where they belong and get some bilstein 4600's or 5100's
problem solved....
lifetime warranty and they should last you a solid 10 years or lot's more

for what it is worth the rancho's just do not hold up, why gm decided to use them is anyone's guess probably the lowest bidder....
the Bilsteins are highly rated
 
Last edited:
OP
OP
D

dbell54

TYF Newbie
Joined
Nov 14, 2023
Posts
14
Reaction score
4
The Bilsteins don't seem to come in complete assemblies, only the bare strut that has to be installed into the spring. My question is more concerning the spring rate of the Z71 compared to a regular 4x4 Tahoe. All the complete assys I can find fit most Tahoes, can't find anything that mentions Z71 specifically. (No lookup anywhere ever gives Z71 as an option, just LS, LT LTZ, even tho Z71 is supposed to be different.) I'm sure I could put any of those in my Hoe, but are they equal to the stock Z71 spring?
 

blackelky

Full Access Member
Joined
Oct 15, 2023
Posts
510
Reaction score
617
The real question is with z71 moog springs and billstein 5100 shocks which setting would it make it cloae to level.
throw those rancho's in the garbage where they belong and get some bilstein 4600's or 5100's
problem solved....
lifetime warranty and they should last you a solid 10 years or lot's more

for what it is worth the rancho's just do not hold up, why gm decided to use them is anyone's guess probably the lowest bidder....
the Bilsteins are highly rated
The real question is with z71 front moog springs which setting on the billsteins would make it close to level.
 

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
23,719
Reaction score
34,682
Location
Stockton, Ca.
The real question is with z71 moog springs and billstein 5100 shocks which setting would it make it cloae to level.

The real question is with z71 front moog springs which setting on the billsteins would make it close to level.
you would need to pick some springs, the shock/strut portion really has no bearing on height. Any new springs are going to be higher at least a little bit until they settle.
 
OP
OP
D

dbell54

TYF Newbie
Joined
Nov 14, 2023
Posts
14
Reaction score
4
That's my point, are the Z71 springs taller/different/stiffer than other Tahoe 4x4s? They have their own RPO of 6TJ/7TJ. I don't want to mess with building up a set, I'm looking for a drop-in install that will equal Z71 standards. The KYB SRM4079 Monomax seems like the likeliest match, but I'm trying to get confirmation.
 

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
23,719
Reaction score
34,682
Location
Stockton, Ca.
That's my point, are the Z71 springs taller/different/stiffer than other Tahoe 4x4s? They have their own RPO of 6TJ/7TJ. I don't want to mess with building up a set, I'm looking for a drop-in install that will equal Z71 standards. The KYB SRM4079 Monomax seems like the likeliest match, but I'm trying to get confirmation.
just call any dealer parts department with the last 8 of your vin and they can tell you the spring part number needed, then shop them on rockauto/amazon/ebay those will be your best prices.
 

Forum statistics

Threads
129,239
Posts
1,812,623
Members
92,339
Latest member
Thekenstar
Top