I had both inside front CV boots on my 98 Forester replaced because they where torn. Immediatly after we took it for a test drive. The brakes now shudder at all speeds. Feels like the ABS is always ingaging. Also the ABS light came on after driving it a few miles and I had no ABS brakes but normal braking worked fine. Once I turned the vehicle off and then back on again. The ABS light went off and the shudder problem came back. Is this somehow related to the new boots?

That's interesting.

 

I just put new brakes on my '92 Legacy wgn. They worked fine until the outer cvj boot let fly. then shudder city. I had to turn the rotors again, The one with the boot problem was warped, the other was perfect. Coincidence...maybe. Perhaps some moly lube is the culprit

 

Jeff

check the wiring for the abs sensor on each wheel you replaced. also check that there is no grease on the front. the abs computer relies on the feedback from this sensor to calculate if the wheel is spinning or not. if it sees it not spinning in proportion to the other wheels, it thinks it is skidding, so it will activate the abs.

 

if the look ok, you could possibly have warped the rotors when you reinstalled them, if you improperly tightened them, but it is better to look at the abs sensor first - that sound more likely.

 

to check the abs sensor:

resistance across the two terminals of the connector should be 1 kohm +/- 200 ohm

 

there should be 44 teeth on the tone wheel, and the sensor should have a clearance of 0.035-0.055in from the front hub and 0.028-0.047in from the rear hub.

 

to check the output of the sensor, you need an oscilliscope. if you have one, post again and i can tell you how to do it...

When you take the rotors off, make sure that there is no rust on the mating surface with the hub. If there is, the rotor will not tighten properly and will wobble.

 

Matt

wow that's interesting ST1100. I also had new front rotors and pads put on a few weeks before the boots got replaced.

I bet the extra heat of breaking new pads contribute to the boot's demise. Interesting post about rust. I noticed some but ignored it, twice now. The rust layer was pretty thin.

 

Did you do the axle work yourself?

 

Jeff

Originally posted by ST1100

I bet the extra heat of breaking new pads contribute to the boot's demise. Interesting post about rust. I noticed some but ignored it, twice now. The rust layer was pretty thin.

 

Did you do the axle work yourself?

 

Jeff

 

No I had someone who works on Subarus do the axle work. He just checked out the sensors today. Only thing he found was some metal shavings collected on the driver side. cleaned it up but didn't fix it. I will be taking it to the dealer next week and see if they can figure it out.

since it sounds like your abs is fine, it now sounds like you might have either warped rotors or maybe the calipers are hanging up on the shaft that they slides on. When you had the brakes done, do you know if whoever did it put sili-glide on the pivot shafts that the calipers ride on?

I would have your mechanic check the runout of the front rotors. If your ABS light has stayed off that probably rules that out as a cause.

I don't think the ABS is fine. ABS light only stays off for a few miles and then comes on. The light stays on untill i shut the engine off. The shudder goes away when the ABS light is on or if I pull the ABS fuse out.

have you pulled the code from the abs computer?

dont have anything to pull the codes. I will be taking it into the dealer monday so they can pull the codes

Well, finally got my car back from the dealer. So far I've spent $700 to get a new rear wheel bearing, new timing belt and replace front crank seal. The only thing they did with the ABS is pull three codes from memory-24, 51, and 26. checked connections and found OK and cleared memory. They didn't even drive a few miles to get the ABS light to come on like I wanted them to. Since I wasn't the one to pick up the vehicle I wasn't able to find out what the codes meant. Now I need to take it in again to get them to finish the job. Does anybody know what codes 24, 51, and 26 mean.

24 - abonrmal abs sensor (abnormal abs sensor signal), front left abs sensor

 

26 - abnormal abs sensor (abnormal abs sensor signal), rear right abs sensor

 

51 - abnormal valve relay

 

probably something with the valve relay, because there are 2 valve relays, one for each circuit, and both of the bad readings fall on the same circuit.

 

the bad abs sensor reading is for a bad signal, as opposed to an "open circuit or input voltage too high".

Does the valve relay need to be replaced? Will replacing it solve the problem?