'99 XC - Need some additional brains here

Post by **wizechatmgr** » 23 Jun 2019, 21:13

Let's start out with the basics...

Known issues:

Both front spring seats appear to be toast, believe driver's strut bearing/mount is also near death

Rear turbo oil return seal is toast and leaking intermittently onto angle gear

Surging during braking that appears to be on driver's side - intermittent gentle almost inaudible thump at highway speeds - follows driveline speed increase/decrease

PCV likely should be done soon, as well as timing belt

Question:
Could the bad front spring seats be causing the thump at speed and surging at low speed braking? Suspect a warped rotor on driver's side due to previously incorrect tension on passenger's side axle nut (corrected) causing tracs to kick in driver's brake.

Post by **Ozark Lee** » 26 Jun 2019, 20:20

The bad spring seats will always make noise, really at any speed. I would not, however, correlate a surge during braking to them.

I guess I need a more detailed description of that phenomenon to hazard a guess as to where to start. Does it act like the engine actually revs or is it a loss of braking power?

Replacing the turbo oil return line seal on a XC is a real treat but it can be done. I think I actually pulled the passenger side axle and dropped the angle gear to do it on one of mine. On the other one I replaced it before I installed the new motor.

The rotor is super easy. I know there is big debate between Brembo and Zimmerman but I have had acceptable service and life out of the cheap auto parts store versions. Pads are a different story. I normally use Mintex Reds but OEMs are a great option, albeit a dustier one. Most of the auto parts store pads will squeal.

...Lee

Post by **wizechatmgr** » 28 Jun 2019, 16:59

Sorry for the late reply,

There is just a tinge of a thump and vibration at speed that correlates with the speed of car movement while driving.

Surging on braking isn't RPM surging but rather it feels like a warped rotor to excess. Feels as if you're pumping the brakes...

I'm wondering if the rotor can get bad enough to cause both...

Post by **abscate** » 28 Jun 2019, 19:23

Have you rolled under and looked at both sides of the rotors?

Post by **wizechatmgr** » 28 Jun 2019, 23:12

abscate wrote: ↑28 Jun 2019, 19:23 Have you rolled under and looked at both sides of the rotors?

I likely need to look again. Planning on pulling both off and looking at them with a straight edge to them. My feeling is the driver's side is badly warped.

Post by **abscate** » 29 Jun 2019, 03:08

I’ve got two spares in the parts bin. We can probably straightedge them on the car, too.

Post by **wizechatmgr** » 05 Jul 2019, 19:33

So, turns out I found out part of this issue today while checking tire pressure.

I found a nail in the driver's front, which likely bled the air in the tire down a bit. Tossed some fix a flat in it for the moment and will work on a proper tire repair tomorrow when the local chain opens. Looks like it isn't in the side wall so it should be an easy fix. I'll have them check the passenger's front as well. This would explain some of the issues.

Doesn't fix what I believe to be the rotor. Looking at potentially checking this out next week while I have my mini-mechanics with me.

Post by **abscate** » 06 Jul 2019, 03:56

Driveway open here but I know I’m a bit far.

greg850r · Post by **greg850r** » 15 Jul 2019, 22:56

I wouldn't rule out a tire causing your symptom.