wheel cuts when i hit the brakes
ive been working all the kinks out of this car for a while now but this one eludes me. it drives smooth until i hit the brakes, the wheel turns itself about an eighth of a turn but the car doesnt veer left or right. occasionally there will be quite a bit of vibration from this as well. what puzzles me is i have had all for wheels off and checked over all four brake setups and everything is working fine so why would it turn. any possible leads on this are greatly appreciated
well if you figure this out please post as mine does it as well...I have changed both entire control arms,front struts,rear shocks,all new front brakes and rotors,swaybar bushings, swaybar endlinks and I can "SEE" nothing wrong. Was nothing wrong before I changed all this stuff, but can't keep it on the road and slowing down while making a brake application can get pretty interesting.
Rabbit may have some input but it seems to me the camber is changing under the stress of braking...mine will pull sometimes always to the drivers side
I ordered the 19mm swaybar to replace the factory 17mm bar that's in there, will change it in a few weeks see what diff that makes.
Last edited by HeavyDuty; 09-23-2012 at 02:12 AM.
i have had this occur a few times. In my case, the only thing i could figure is a caliper. But if it is more common than just me i will look more into it over the next few days. I need to check my brakes, suspension etc anyhow i have a noise up front..
I was leaving a store the other day pulling out of the parking lot and stopped in the entrance way, the steering wheel was almost a half a turn from the straight ahead position...wheels where straight ahead so it gets worse if say the rear wheels are on level ground and the front wheels are headed down hill and you stop. I have noticed on mine at least there seems to be a slight clearance between pad and rotor unlike any other I have ever seen where they are pretty much rubbing the rotor..if that clearance through bleeding of brakes ect ends up all on one side it creates a one brake apply before the other scenario, the steering wheel movement IMO is a result of one wheel braking and a change in the camber/caster. I have not been able to bleed out this clearance which I noted...but I can take my calipers on and off easily from the rotor and on any other car I have ever worked on, they usually need to be encouraged off.Originally Posted by petrified.rabbit
A powerbleeder vs the pump and hold method might create a different end pad/rotor clearance or somehow balance out the clearance which exists. It seems to me the design was intentional to prevent any brake drag at all (imo). I did my front brakes to try an eliminate this pull, I checked the caliper operation...I see nothing that points to the caliper, and I will depending on the lay of the land get the same type of pull to the passenger side with the same steering wheel movement....rear bushing's can create this, but mine "look" fine. I also thought maybe it was the bushings in the front subframe but I don't see any movement there either.
Keep us posted Rabbit...I have a swaybar coming and some ultra racing supports...going to make this car work right if it kills me.
It's that looseness of the pads that I was talking about with the caliper. Almost like the caliper is "bleeding down".
But again thought it was only me, I was going to check carrier, if there is a residual pressure difference, etc.
Yes...pump and hold brake bleeding can create air bubbles in the fluid, maybe this system for whatever reason creates more airbubbles than normal. I will try vacuum pump when I do the next flush. But as Snow mentioned, it doesn't always pull the steering wheel just goes off center. If I am making a light brake application and do a lane change and there happens to be some wear marks in the pavement my steering wheel goes back and forth gotta keep both hands on the wheel if you let it go I am sure it would turn itself. I call this "over reactive steering" the application of the brakes just increases it and makes it worse.
Way back when I bought this car...GM told me a "defective swaybar" could cause this issue. Which is why I am changing it now three years later, with no warranty. But it sounds to me Rabbit with all the mods you have done, swaybar isn't the issue is it.
Rabbit do you have any idea what the differences are in the different GM Aveo rear axles? I have a 96653128 installed in here and a VIN search says that axle part number does not fit my VIN...I am suppose to have 96494500....this 96653128 was installed under warranty because my original one was bent at 8500 KM...I can't seem to find any spec's for GM parts....
Ok I installed the new stiffer swaybar GM 96449097 which fits the late 2006 and 2007 Aveo's. I measured it at 18mm the OEM bar that was in my car measured 17MM. The GM 96449097 was listed as a 19mm bar but didn't measure out that way. They are identical in everyway a little trucky to snake in and out but the kid and I managed it with a few words of encouragement. I used the MOOG K90393 universal bushing kit on this, had to cut 1/4inch of each side of the Aveo OEM bushing brackets to fit the MOOG bushings and had to trim 1/4inch of the base of the MOOG bushing as well....it all fits like a glove and looks great. I filled the deep groove in the bushing bracket with filler to give it some support as well.
This is the single biggest improvement I have noted in car handeling well worth the $ 100.00 bucks total cost for the project, but it has not corrected the wheel cutting, did reduce it some though it's almost starting to drive like a real car now I can drive over a railway crossing without having to keep both hands on the wheel...will post some pics of the brackets ect later.
When bleeding front wheel drive vehicles, they require a cross bleeding pattern due to the system being a split diagonal type, which means one front wheel and one rear wheel is grouped on one side of the master cylinder and the other sides are on the other half. This type needs to be bled in a cross pattern, usually RR, LF, LR and RF. If not properly bled, air will be trapped in one side and cause the other half to do the majority of braking. Does this apply to us ?
Last edited by HeavyDuty; 10-14-2012 at 04:11 AM.
ABS is bleed slightly differently. But i Always bleed furthest to closest. If the system is truly split, and you dont run low on fluid, you could technically only bleed one side of the split. BUT even bleeding the backs first is just bleeding the farthest part of each system... make sense?
Interested in seeing what you did in your repair.
the part number i think changed "maybe" with year but might be post daewoo availability.
The design solves several issues associated with volume and big calipers more than wheel cylinders actually. When CAFE standards for the OE's forced them to design more towards fuel mileage, low drag calipers became the norm. Low drag calipers have square-ish seals that retract the pistons further than necessary to make sure that they don't drag on the rotors which was supposedly good for 1-3% better mileage. Since the pistons have further to travel before making contact with the rotors, the quick take-up MC achieves this with the primary bore. This applies to us also....
I am not sure on the part number change rabbit, I just ordered that bar by that number and I got an 18mm it was $ 85 bucks, but it is good stiff enough 19 would be too much imo. My kid is gone to camp...he runs the pics LOL I don't know how.
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