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Aluminum suspension parts?

While looking at 2011 Buick Regal noticed it uses aluminum for the lower link in it’s independent rear suspension “for reduced weight” and unspecified aluminum components in the MacPherson strut front suspension “to optimize unsprung weight”.

Our roads have numerous & sometimes unavoidable potholes 6 months of the year. Will the aluminum parts stand up to that pounding as well as steel or am I asking for trouble & costly repairs?

I have a 1988 Toyota Supra that has aluminum suspension parts. Original parts for 255,000 miles and 22 years. It’s been driven robustly and shows no signs of damage or fatigue. Also, the Corvette has used aluminum suspension parts for the last couple of decades. Nothing to fear.

I think you have to realize that the aluminum used in those suspension parts is not the same as the stuff used to make your lawn chairs.

As BustedKnuckles stated, there are a number of high-performance cars that have used forged aluminum suspension arms for a number of years. I have never heard of any unusual or catastrophic failures of those aluminum parts.

The aluminum is FINE…It’s the MacPherson strut design that has limitations on poor roads…As long as your roads are PAVED, you should be okay…

Thanks for responding. You didn’t mention whether potholes are a problem in your area. If not, do you think that would change things?
re: unsprung weight - The car comes with alloy wheels but I’d like to use steel wheels to permanently mount my snow tires. Will the heavier wheels cause/handling or ride problems?

No problem using steel wheels. They may ride slightly rougher, but if they’re the smallest size you can use on your car, they may actually ride smoother. Check, see what they recommend for winter tire/wheel combinations. They may be a smaller wheel combined with an appropriately taller tire to retain correct overall diameter.

My Lincolns have all aluminum suspensions (as well as the hood and trunks), and the roads can be pretty bad around here. I hit one hole so hard that it cracked my battery and broke the grease seal on the wheel bearing. There was no damage to the suspension.

It seems that aircraft do okay on landing too, so I don’t see why you think this is a bad idea.

The one catch that I know of is that you can’t safely unbend aluminum. If you are in a crash, any affected parts can’t be unbent. They have to be replaced.

To give you an idea, an aluminum part, to meet the same strength as a steel part, has to be thicker. So the part is larger than the steel part, but because of the material, weighs less.

The aluminum parts will easily stand up to the abuse they will see due to the potholes, and, they won’t rust out as steel ones would.

As for using steel wheels with winter tires, if they are considerably heavier than the stock allow wheels, that might lead to slightly reduced life for the wheel hub and bearing assemblies. If you can get the dealer to throw in another set of allow wheels when you purchase the car, for a reduced price, I would recommend that over steel wheels.