Brake Issue Q's?

[megaladon6]

2003 jetta, no real braking issues, maybe a slight pull to the right on heavy braking.
then i replaced all 4 rotors (zimmerman) and pads (trw) along with the front hoses (SS). i took it easy for about 100-150mi to break them in. then one day in heavy traffic i started to notice a wheel shake. when traffic opened up then crash stopped i had a SEVERE wheel shake and strong pull to the right. but it didn't come back. the minor shake seems to come and go. it's fine at the beginning, then starts after about 15-20miles on the highway (btw, i barely use my brakes normally), then it goes away after about 5-10 miles. but sometimes it never happens at all.
i loosened and retorqued all 4 wheels and most of the minor shake is gone, but randomly the severe shake comes back! even when it doesn't happen the car tends to go to the right--but not always.
i have checked the rotor/caliper temps after a drive and the FR is 180*F, FL 120*F, both rears are about 130*F. i think these are normal temps (except for the difference in fronts) but not sure.
any ideas?
thanks!

 

[jcrews]

Look at the control arm rear bushing on that side.

 

[megaladon6]

i forgot to mention; when i pull the e-brake, the car stays straight. but if i pull the e-brake and step on the brakes the car wants to pivot to the right.
also, after i did the brakes, the pedal was really high and engaged instantly. when i did the re-torque, i pushed the calipers back. now the pedal feels more normal.

 

[megaladon6]

while the bushings don't look new or anything, they are not dried out or cracked.

 

[jcrews]

Check the outer tie rod ends. Is there any thunking or dead zone in the steering wheel when you turn it slightly when stationary? Were the caliper slides tightened to 30 N-m and the wheels to 120?

 

[megaladon6]

nope, steering is fine, no slop and no play. all bolts are fully tightened, wheels at 85ft-lbs.
i rechecked all the bolts/nuts and they were all still good (though i did forget to properly torque the lugs the first time)

 

[megaladon6]

went for another drive, no shudder with the brakes.
but the random pull to the right is still there. like i said, random. it didn't do it for about 15mi on the highway, then it started-bad. i turned around and now it either didn't do it, or it was slighter. i did notice that it does not turn the steering wheel when it happens.
also, pass front and drivers rear were hotter than the others. front were about a 60*F difference, rears about a 30*F diff.
i would normally think/agree that it's bushings (probably the rear torsion bar), except for the fact that it started right after doing the brakes.

 

[jcrews]

What did you lubricate the slide pins and backing plate contact surfaces with, and was there any slide pin corrosion? A pull to the right might indicate the left caliper is stuck, which shouldn't happen after a brake repair.

 

[megaladon6]

i originally used some "brake lube" i had --it does appear to have thinned out and may have gotten on the rotor. that could have caused the random shudder, i think. but today i cleaned everything and bought some good hi-temp brake grease (same stuff we used to use at my old shop with really good results). and i made sure that it can not get onto anything.
all slider surfaces were either clean or replaced.
thanks!

 

[jcrews]

Bleed all 4 calipers and see if that helps with pulling.

 

[megaladon6]

god this thing is pissing me off! now the pull to the right is gone, but the shake is back! not nearly as bad, but there.
the weird part is it usually happens on the way to school, but is fine on the way back.
BUT, as there is a very slight steering wheel shake that seems to change with turns, and the complete unpredictability, i'm revisiting the bushing possibility.
so, i've ordered new control arms and rear axle bushings. (it also only seems to happen over 60-65mph. and i THINK the wheel shake changes when i come off the throttle)
plus, of course i'm going to re-bleed everything, hopefully my friend can help and do it right! (BTW, now 3 brakes are running at a near equal brake temp. the front left is the exception.) plus i'm going to try and extend/re-compress the caliper just in case a small piece of dirt got in there.
thanks for all the help, i will let you know what happens!

 

[megaladon6]

90% fixed! it was the rear beam bushings. i think that jacking up the car point by point put just enough stress on the bushings to push them over the edge.
now i may still have a slight pull and a very slight vibration in the steering wheel. but both are very slight and more than manegable
but control arms should be on the way any day, and this weekend i will be re-bleeding the brakes AGAIN. after i did the bushings, and changed the brake hoses, the brake pedal is a touch low and soft. that's after vacuum and gravity bleeding.
do MK4's with rear discs have a ride-height variable proportioning valve?
thanks!

 

[jcrews]

mk4 cars use EBD (electronic brake distribution), which is ABS software. If the master cylinder was drained, you need to run basic settings to bleed the ABS module.

 

[megaladon6]

well, if you're ever in CT let me know, i owe you a beer. front control arms finished the fix!
thanks for the help