Aluminum front control arms.

jabartram · 02-14-2011, 11:45 PM

are there any other benefits (besides weight) to having the aluminum control arms? my factory stamped steel control arms already have poly's installed.

Chipmunk-Alero · 02-15-2011, 12:17 AM

No, but I think they would be worth your while. I dont know the weight difference, its not much. 5-10 lbs.

Since the aluminum ones are lighter it means less unsprung weight on the front suspension. I dont know if that makes the handling better or worse though. With full suspension and good brakes it wouldn't matter.

Cliff8928 · 02-15-2011, 01:54 AM

I would think that they'd have to be more rigid.

widbyj · 02-15-2011, 11:52 AM

Lighter is always good but I probably killed that by my choice of oversized brakes, wheels and tires. I have a set of poly bushings ready to be installed but no press at home. My hope IS that they are stiffer and complete the tightness of my front end. I guess I'll just have to wait and see....

kwhauck · 02-15-2011, 03:45 PM

Quote:

Originally Posted by widbyj

Lighter is always good but I probably killed that by my choice of oversized brakes, wheels and tires

True and you had the chance to change all of those. Lightweight wheels matched with lighter tires, and then say no to the oversized brakes....

widbyj · 02-15-2011, 06:57 PM

Quote:

Originally Posted by kwhauck

True and you had the chance to change all of those. Lightweight wheels matched with lighter tires, and then say no to the oversized brakes....

I can always go back, I kept all the original stuff in case of sale or changes. Wouldn't want to go back to understeer and slow stops though...

jabartram · 02-15-2011, 07:39 PM

does anybody know the part numbers for the energy suspension or prothane front control arm bushings?

widbyj · 02-15-2011, 08:26 PM

"Prothane 7-234" says "GM J-Body Front C-Arm Kit 95-04"

This looks correct but cannot verify until my arms get here (car has stock parts atm). I believe I got this set through MPRacing...

01GrandAm · 02-15-2011, 08:41 PM

This is what I weighed them at when I did mine:

Stamped steel arm (with stock bushings and ball joint) 7.8 lbs
Aluminum arm (with poly bushings and ball joint) 6.4 lbs

A weight savings of 1.4 lbs per side.

If you have the steel arms with poly bushings, I wouldn't bother as I feel your money would be better spent elsewhere.

02-16-2011, 06:10 PM

Quote:

Originally Posted by 01GrandAm

This is what I weighed them at when I did mine:

Stamped steel arm (with stock bushings and ball joint) 7.8 lbs
Aluminum arm (with poly bushings and ball joint) 6.4 lbs

A weight savings of 1.4 lbs per side.

If you have the steel arms with poly bushings, I wouldn't bother as I feel your money would be better spent elsewhere.

Agreed.
The only reason I have aluminum LCAs is because I wanted poly bushings.....and tejohnson was selling his.

widbyj · 02-16-2011, 09:23 PM

Quote:

Originally Posted by 01GrandAm

If you have the steel arms with poly bushings, I wouldn't bother as I feel your money would be better spent elsewhere.

Agreed.

However I'm well on the way to having the most expensive Malibu ever - Jokes on me!

falloutboy · 02-17-2011, 02:01 PM

The reason for the aluminum control arms - is the transient behavior and eigenfrequency of aluminum compared to steel.

The fact that they weight less then the steel is normally an indication that they arent as "strong" as steel ones, but the fact that they are cast instead of stamped (steel) they are probably stronger or as strong as, in the parts where it counts.

What you'll gain from OE aluminum CA is a quieter, less NVH ride compared to steel.

I felt it in my own hands and butt - as I changed my 99 al. CA to stamped aftermarket steel ones (ripped my ball joint boot - couldnt get a replacement for the al. ones) - no I feel minor road inconsistencies more and stronger then before.

So from an engineering point of view - you'll ride better with OE aluminum CA.

widbyj · 02-17-2011, 03:08 PM

Quote:

Originally Posted by falloutboy

So from an engineering point of view - you'll ride better with OE aluminum CA.

Thank you very much for the explanation!

I thought there was an engineering reason for the improvements but wasn't sure. My degree is Electrical Engineering, not Mechanical... I really didn't think that the slight weight reduction itself would do much for me, I've already added weight through larger wheels, wider tires and bigger brakes.

Curious though, you mention not being able to find a replacement ball-joint boot, will I have trouble finding the proper ones here also? I was thinking of putting new joints in before installing the arms... Also, would glass-bead blasting and then powder-coating be worth doing, they put corrosive slime on roads around here in winter?

Thanks again!

falloutboy · 02-18-2011, 05:56 AM

Moog NOW has balljoints for al. Arms - but they are more expensive than the ones for steel.

bead blasting would be a good thing - seals the surface. If powdercoating al. Arms is possible or wise, you have to ask a professional powder coater.

Although the A-Arms dont get "much" damaged by the corrosive winter stuff, more in danger are all other steel and painted stuff down there.
Sway bar, struts, bolts, nuts and so on.

widbyj · 02-18-2011, 11:18 AM

Can you tell me exactly what year/vehicle the aluminum arms originally came on? My dealership parts connection could not find any difference in the ball joints listed, cost about $80 each. I don't want to order the wrong ones and then have to pay restocking.... Thanks

falloutboy · 02-18-2011, 01:40 PM

I only have a 99 LA1 - but I heard that the early Aleros had 'em - later not.

according to Rockauto
MOOG Part # K6701 - Frt Susp; Lower; w/Aluminum control arm - €41.71

MOOG Part # K6527
Frt Susp; Lower; w/stamped steel control arm - €41.79

widbyj · 02-18-2011, 02:35 PM

FYI - Aluminum Control Arms may be found on:

Any 2005 GrandAm
'99 to '04 GrandAms & Aleros - This was according to Rock Auto and is WRONG

1999 Malibus only, early production - GM dealer research
Still available new for $280 each at dealer, steel is less than $100

The proper ball joints are different although the price is only $0.10 different here.

I'll check at the stealership and post their prices for comparison... Too high to bother with and are inferior to the new Moog design

Cliff8928 · 02-19-2011, 01:15 AM

I have definitely only seen the parts listing from GM for '99s

I have a new one sitting in the garage...

widbyj · 02-19-2011, 03:15 AM

Quote:

Originally Posted by Cliff8928

I have definitely only seen the parts listing from GM for '99s

You are correct sir. My dealership connection verifyed this today. Not used in production due to cost cutting. Some failures reported, replace with steel in warranty. Highly recommended to have them glass bead blasted, this is supposed to toughen the surface and reduce/prevent cracking. I'm looking forward to giving them a try very soon...