WARNING to autocrossers!
 

If you are autocrossing a Cobat SS S/C (don't know if others are affected), you may want to replace your steering knuckles.

I was at an autocross event today and some of the GM Tech Center employees were autocrossing some GM Corporate vehicles. There were two or three solstice's and one Cobalt SS S/C. Well, after about 6-7 runs, the Cobalt comes around a sharp left turn that immediately transitions into a right and right after the transition, the left front of the Cobalt dropped. The wheel was completely caved into the fender and had to be moved off of the course on wheel dollies. The GM employees said that they knew it would probably not last.

I know that GM is offering steering knuckles for competition use for the Cobalt, which should be much stronger than stock. I will post the GM document ASAP that describes the competition knuckle, but I have to find it.

ive heard this could be a problem, do you know if it is also an issue with the ls models? why would gm release a so called sports compact that cant take the abuse they know its gonna have to endure. well 2 1/2 years till i trade up anyway, hopefully itll make it.

http://www.alldata.com/tsb/General-M...01A/80011.html

doesn't specify cobalt ss/sc tho....

This actually might be a blessing in disguise for autocrossers who are looking to stay in the stock classes and obtain as much negative camer as possible. It looks like the replacement knuckle will allow for as much as -2.25 degrees of negative camber. Does anyone know how much is available in the original knuckle?

At any rate, for those that are driving competitively, this is definitely something to look into not just for a performance advantage, but also for safety.

Redwing excellent info, thanks:twothumbs

im pretty sure if you have your knuckles replaced you cant stay in the stock class. the scca doesnt care if gm suggests they be replaced, as far as theyre concerned its not a stock suspension piece and therefore not elegible for stock class. the only changes you can make is a change of shocks(when theyre released), catback, an alternate air filter element, and wheels of the same size and offset.

I noticed this info awhile back in GM Service Info. I attempted to get info from GM on price and avail., but they had no info and the #'s weren't any good at the time. This was about 1.5 months ago, though.

You can also change the front stabilizer bar!

besides the ability of possible larger avalible suspension changes in camber and such whats so differant about these then the stockers?

I ask this becasue i've broken my rite front whell hub...it brooke for a a un-known reason so are these made any differant?

In re-reading my 2006 rule book, and this has been pretty consistent for as long as I've been autocrossing, this modification would be allowed if it were simply re-worded. Since the words "for competitive purposes" appears in the TSB, it would NOT be allowed under SCCA Stock Class Solo rules (unfortunately!)

John Heinricy, if you're reading this, have that wording changed in the TSB to something like "heavy-duty replacement" so that it would be a legal stock class change :twothumbs .

Do you happen to have the part numbers?

same knuckles used in the pontiac/saturn roadsters ?

anybody know how or why it might be stronger than stock?

88958710=LH knuckle
88958711=RT knuckle

I will check into these some more to see if they exsist yet.

perhaps it's stronger because initially it was never imagined the car would be used in this type of every day driving scenario until they decided to make this up to handle the issues people might be having with them in a non-autocross situation

Just checked, the #'s are not on file, but are avail. from source and stock is avail. (the dealer needs to call Partec for avail.) The cost, ouch, but maybe worth it for the strength. List is $335 each, cost would be around $300 each.

...the steering knuckles don't affect the alignment. Those are the stock alignment specs for the SS/SC...not something that is changed by steering knuckles. It says that in the bulletin if you read through it (I actually had to read it twice to get that though)...something to the effect of to inform about the availability of the knuckles and to inform those interested in the proper alignment specs for the car.

how would scca know if you have changed them? i mean couldnt you change them, and still say it was stock? i dont know how they inspect the car, but i wouldnt think they would go and look to see if they are stock or not, and it isnt like the new gm ones have like aftermarket knuckle written on them..... again i have never auto x'd before, so i dont know how scca would find out...???

At any SCCA sancitoned autocross, there is what is known as "impound", where fellow competitors can examine each other's car for conformity to the rules. If a competitor's car is found to be in violation of the rules, a protest can be filed and the results for that competitor can be disqualified. Usually these impounds do not happen at the local level, and for the most part, locally, the guys who are winning may not care if you are running a part that is "for competitive purposes", but at bigger national events, that is something that will get protested without a second though.

As far as any alignment advantages, as fastSS06 pointed out, there is none to be had. I mistakenly thought the steering knuckle would have been the entire hub.

GMP ST racing team uses grand am knuckles and hubs up front and Grand Hubs only in the rear (not sure about the rear if it is just hubs). then they redrill the rotors to fit. this was also seen on the show tuner challenge for the time attack build.

is this the same part? is the hub strong enough for competition? GM lead me to believe the grand am hubs were better?

another thing is wheels are no longer useful but if you want a specific rim now there is far more available in the grand am bolt pattern

right, but i really doubt anybody would know the difference between a stock knuckle and the replacement

You would be surprised at National Level events just how much your fellow competitors know. In this example, someone will know exactly what the part numbers are for the replacements and actively look for it at impound.

Put a call in to GM found out that the steering knuckles do indeed exist for the right and left front at $270.00 each..!!! It probably requires disassembly by a press and hub puller as well. Doing more research now on these.

updates?
 

Anyone hear anything else on this or have a knuckle blow out on them?

Well, I spent the whole weekend at the track auto-xing .... and no issues here. Made a 65 mile trip back home as well.

I still have thought about getting them this fall just in case....lol