This has probably been discussed but a quick sift through and I couldn't find anything specific. I have always had this with my 1998 Astro AWD. Now has 180,000 KM. On the flat don't notice anything under braking, but coming down a hill and have to brake now and again to stop speeding up, and this is around 50 KPH, and I get what I call the death wobble. It seems to be only on hills round town. Perhaps when the rotors are not quite hot yet and heating up. Out on the highway on day trips down hills at higher speeds on highways doesn't seem to happen.
You probably know what I mean, during braking on hills the front wheels feel like they are wobbling and cause me to brake gentler than harder beacuse it will be worse. The steering wheel vibrates. Whole front end shudders. If brake gentle and not sudden hard applications, then I can keep it to a minimum effect.
I have had this van for about 8 years and its always been like that. I have even changed rotors pads and drums and tires and shocks over the years only to notice it still does it! Have had rotors turned for obvious warped rotors years ago, did not help the brake wobble thing. Have got fairly new Raybestos rotors, drums, pads and shoes. I replaced all 4 ball joints on the front (mostly due to split boots and dirty greasy water comes out when I did a grease job!) so did the ball joints as a matter of maintenance. I have then had it in recently for wheel alignment (its had one a few years back too), all tie rod and other joints are tight. I had recently put Moog idler arms too. This wobble still occures. With new tires, rebalanced, old tires too, still the same. Wheels rotated, still the same.
I learned to live with it as I was basically the only driver of this van. Until two months ago my son got his drivers license and said he thought he'd broken something when it did that for him. Stupidly I'd forgot to explain to him not to exceed speed limits on hills and then brake hard!
Is this common with these vans? Has anyone ever fixed theirs and found out what it was? Right now theres not much that can be done to it thats not been done already.
What I have always thought causing this is brake pad residue on the rotors, you know when they are hot when you park, or what ever causes that outline of the pad on the rotors, residue like staining that must wear off soon after driving and braking again will polish it off after awhile I suppose. So I assume round town, down hills, under load, cold brakes warming up, that when braking on this type of rotor/residue condition causes grabbing, and on each side at different intervals, causing more or less pressure on the rotor and the wobble is like a pulling as each side gets more or less braking for split second - Are you with me?
EDIT: I should also add that all these years I use a torque wrench on all the lug nuts so as not to cause warping rotors.
Thanks.
Nils
You probably know what I mean, during braking on hills the front wheels feel like they are wobbling and cause me to brake gentler than harder beacuse it will be worse. The steering wheel vibrates. Whole front end shudders. If brake gentle and not sudden hard applications, then I can keep it to a minimum effect.
I have had this van for about 8 years and its always been like that. I have even changed rotors pads and drums and tires and shocks over the years only to notice it still does it! Have had rotors turned for obvious warped rotors years ago, did not help the brake wobble thing. Have got fairly new Raybestos rotors, drums, pads and shoes. I replaced all 4 ball joints on the front (mostly due to split boots and dirty greasy water comes out when I did a grease job!) so did the ball joints as a matter of maintenance. I have then had it in recently for wheel alignment (its had one a few years back too), all tie rod and other joints are tight. I had recently put Moog idler arms too. This wobble still occures. With new tires, rebalanced, old tires too, still the same. Wheels rotated, still the same.
I learned to live with it as I was basically the only driver of this van. Until two months ago my son got his drivers license and said he thought he'd broken something when it did that for him. Stupidly I'd forgot to explain to him not to exceed speed limits on hills and then brake hard!
Is this common with these vans? Has anyone ever fixed theirs and found out what it was? Right now theres not much that can be done to it thats not been done already.
What I have always thought causing this is brake pad residue on the rotors, you know when they are hot when you park, or what ever causes that outline of the pad on the rotors, residue like staining that must wear off soon after driving and braking again will polish it off after awhile I suppose. So I assume round town, down hills, under load, cold brakes warming up, that when braking on this type of rotor/residue condition causes grabbing, and on each side at different intervals, causing more or less pressure on the rotor and the wobble is like a pulling as each side gets more or less braking for split second - Are you with me?
EDIT: I should also add that all these years I use a torque wrench on all the lug nuts so as not to cause warping rotors.
Thanks.
Nils