Control Arms help for others 09 Tahoe LTZ 5.3L Flex

[jared999]

After spending about 2 hours on the 'net, I will answer my own questions in hopes that it may help someone in the future.

Is it normal to have iron/steel upper arms and lower aluminum arms?
Apparently, yes. Aluminum was used to save weight on the LCAs. However, the weight savings doesn't equate into improved gas mileage. From what I can find it does not negatively alter driving experiences.

Info #1:
Black control arms are likely steel or iron.

Info #2:
Apparently the vast majority of 07-14 Tahoe knuckles are iron.

Can I get rid of my aluminum control arms and replace it with cheaper iron?
Yes, as long as your knuckle is not aluminum. Apparently iron control arms won't fit into aluminum knuckles. See info #2, also.


rock auto shows on some control arms "Exc. Aluminum Steering Knuckles"
You will need to verify if you have aluminum. Can be done by sight and using a magnet. Aluminum is lighter in color and is non magnetic (typically). You may need to do some scrubbing on your knuckle to get a good look at the color.

 

[OR VietVet]

Doesn't RA state the RPO codes that are attached to the options?

You are giving no vehicle info so we can look the application up and compare what you have said.

 

[jared999]

Doesn't RA state the RPO codes that are attached to the options?

You are giving no vehicle info so we can look the application up and compare what you have said.

Sorry, I have rewritten the OP probably 6 times and deleted pertinent vehicle info by mistake. This was fixed.

RA doesn't list RPO codes for the CA's that I am seeing. Sometimes it will give an Engine VIN digit, but not all parts do that.

 

[OR VietVet]

Sorry, I have rewritten the OP probably 6 times and deleted pertinent vehicle info by mistake. This was fixed.

RA doesn't list RPO codes for the CA's that I am seeing. Sometimes it will give an Engine VIN digit, but not all parts do that.

If I was you, I would put all pertinent vehicle info in your signature and then every time you post, it is all there. All of my info is there in my signature.

 

[jared999]

This older thread helps me a little. I guess it all comes down to which knuckle I have.

Control Arms and Ball joints

@randeez probably can answer this. I remember he posted weight differences between the iron VS Aluminum arms. He is also running the newer aluminum spindles off the K2XX trucks if I remember correctly. theyre about 3/16" thicker

www.tahoeyukonforum.com

 

[OR VietVet]

I think, if you look at the part specs for the steering knuckles and arms, there may be differences that you can compare with. Or, post the last 8 digits of your VIN and hopefully @915_Tahoe will see and he can give you your GM part numbers and then you can look all that up at RA.

 

[jared999]

Thanks for the assistance.

If I have a steel knuckle the plan is to go with iron all the way around. It's heavier, but more durable and a lot cheaper.
When I see daylight I'll get in there and clean up the knuckle a bit and try a stronger magnet to see what the material is vs. this flimsy fridge magnet.

 

[swathdiver]

Aluminum was used to save weight. However the weight savings doesn't equate into improved gas mileage.

The 2009-2010 Tahoe and Yukon XFEs used aluminum control arms to save weight.

I believe the intent to using aluminum was to save weight and keep the curb weights of the various configurations the same.

RWD, 4WD, iron block, aluminum block, never understood who got what!

 

[jared999]

The 2009-2010 Tahoe and Yukon XFEs used aluminum control arms to save weight.

I believe the intent to using aluminum was to save weight and keep the curb weights of the various configurations the same.

RWD, 4WD, iron block, aluminum block, never understood who got what!

XFE was only 2WD, so this kind of makes sense. By trimming a few pounds here and there, GM was able to achieve a very slight increase in MPG.

Except for XFE 2WD, seems like the rest of 07-14 Tahoes are steel knuckles. I wonder if the Z71 is aluminum or steel?

 

[swathdiver]

XFE was only 2WD, so this kind of makes sense. By trimming a few pounds here and there, GM was able to achieve a very slight increase in MPG.

Except for XFE 2WD, seems like the rest of 07-14 Tahoes are steel knuckles with a possibility of Z71 being aluminum.

I've seen AWD Yukon Denalis with and without depending on the year, 2007-2008 Suburbans with them and my 2009 Yukon XL has steel. The "logic" also seemed to have changed with regards to which configurations got which engine. A 4x4 Suburban and Yukon XL for the most part got the all aluminum 5.3 while the RWD of the same got the iron block LMG. After about 2010 it seems all of the short wheelbase 5.3 trucks got the LMG. I tried to make an excel spreadsheet but gave up.

Yes, all the tweaks to the XFE gave them an extra 1 MPG which was negated with the arrival of VVT in the 2010 engines. Always wondered if those 2010 XFEs got the old or new LC9.

 

[jared999]

new control arms

 

[swathdiver]

new control arms

I see new springs and struts too!

 

[mikez71]

Except for XFE 2WD, seems like the rest of 07-14 Tahoes are steel knuckles with a possibility of Z71 being aluminum.

My 2012 Z71 has iron knuckles and steel control arms I'm fairly certain..

 

[mikeyss]

My 09 Tahoe LTZ 4X4 has aluminum lower control arms. It also has the aluminum L9H. I'm not sure if a 6.2 weighs more than an aluminum 5.3 though, so I'm not sure why my Tahoe has aluminum lowers. It could be all about weight savings, since the LTZ has all of the fancy features that add weight, haha

 

[petethepug]

I found this list of NNBS vehicles with aluminum lower control arms. Check out the compatibility chart in this link …

GM Genuine Parts 19256481 | Front Lower Suspension Ball Joint (Vehicle Custom Fit)

Fits: 07-14 Cadillac Escalade, 07-13 Cadillac Escalade ESV, 07-13 Cadillac Escalade EXT, 07-13 Chevrolet Avalanche, 07-13 Chevrolet Silverado 1500, 07-13 Chevrolet Suburban 1500, 07-14 Chevrolet Tahoe, 07-13 GMC Sierra 1500, 07-14 GMC Yukon, 07-1

partshawk.com

I tried to make an excel spreadsheet but gave up.

 

[Doubeleive]

you can change the whole setup if you really want to...
regardless the last 8 of your vin tell's all, just reach out to any gm dealer parts department

 

[petethepug]

Hahaha GM even had an xfe badge if you opted for the option. That’s almost as prestigious as the near zero emissions badge on Subaru & Hondas