Hi gang,
Any ideas welcome. I'm asking on behalf of my sister so might not have all the info...

2003 2.5 D5 geartronic UK spec
Reasonable service history from previous owners
Owned less than a year, problem occurred in last 2 months. Currently maintained via an indie near Windsor.

Front divers wheel presents the outward symptoms of binding and occasionally locking 'on' such that the vehicle cannot be moved or present sever resistance. Posing a big problem as the vehicle cannot be relied on for long runs as this is typically when the prob occurs.
Apparently the callipers have been checked and pronounced OK ( I ASSUME the pads too)
No ABS or other status lights to hint towards problem
Havent taken the stub apart to see for myself and the problem is not easy to recreate as it is not consistent but I'd have expected to hear of some clues from the repairer (corrosion, signs of overheating, damage to pipes etc).

Braking is generally OK for stopping and does not sound compromised. Wheel & braking system does get v hot if the problem is not detected and rescue services called. I believe the brakes eventually fail if driven on at motorway speeds which is a big concern.

Any expereiences of the same or any known issues in this area?
One repairer has suggested ABS sensor could be the cause but I cannot see how this could be the case for locking 'on'. Particularly with no warning lights from sensor static or dynamic tests.

My thoughts are:
1 calliper jamming
2 pipes damaged & not allowing fluid back
3 ABS block not auto-returning fluid

in that order...

Cant imagine it is transmission related?..

Appreciate any contributions before the bills start to mount up for changing the wrong stuff :-)


G

 

Hi

Just wondering if your sticking front brakes were ever resolved & how?

I have a virtually identical issue on my 2004 UK XC90 - after having discs & pads replaced & calipers overhauled several times it still occurs. It's only ever been an intermittent problem and only ever on the offside front brake but when it happens it's horrendous - causes the whole car to shake and drastically reduces braking power. Then, once all has cooled down it'll be fine for a few weeks.

It seems that replacing the discs & pads resolves the problem for 2-3,000 miles or so but after that it always returns (I've had 4 sets in 18 months now - all under a repair warranty after the first set were fitted).

My local trustworthy garage can't solve it & nor can my main Volvo dealer. Local garage thinks it may be flexible pipes but Volvo disagree. I was considering having both the calipers & flexi pipes replaced but am concerned that I'll spend the money & still have the problem. Particularly as some "threads" on this site refer to an ABS problem as a possible cause.

Can you tell me if your issue was ever resolved & how?

Thanks in anticipation.

Murray

 

what is the condition of the pads/rotors when you take them off? after 2-3k miles they should have very little wear (the disc can be measured with a micrometer). If that's not the case I'd guess there is something wrong with the caliper or the abs system. your mechanic may be able to rule out the latter by temporarily disabling the abs (fuse/relay pull) next time it happens.

 

Hi Murray,
I don't remember what my Sis did in the end. I have a suspicion that they never fixed it for sure but the symptom was identical to yours and on the offside. I will ask when I can for you in case they found the root cause.
The prob was so severe that the car would not actually move away once ground to a halt I remember and it was completely random when it occured (not always during a braking phase).
I was always suspicious of a caliper seal getting inverted in the Master but that would not explain the offside wheel only.
G

BTW, my post should of course read 2.4 Geartronic :-)

 

Hi forum
I have 2003 xc90 for 4 years done 96k. Great car, love it, total luxury workhorse. Yesterday, managed to get down my very tight 400 yd lane realised that it was slowing all the way downhill. Stopped just before accessing main road luckily with Front Off side wheel locked up. Strange. In this case unlikely to be a sticking caliper / piston as I use car regular and no hint of one side brakes being sluggish etc which might have indicated a sticking/seizing/ rusting caliper or brake piston cylinder. Jacked wheel up and it was solid. Good pads etc. Tried a little hammer work to solid metal parts of caliper to free off any mechanical 'lock-up'. No use. Thinks !!!!!!! 'Modern ABS stuff" - (as I am 55 and last worked as a good thinking mechanic 30 years ago after working and being brought up in a garage since age 10) - Could it be that one of these 'auto-matic self braking sensors' (or whatever they are) is stuck on and not releasing the brake fluid back? Unloosen brake bleed nipple = spurt out and release of disc. Hmmm. Press brake again = solid. repeat of above and hey presto = release disc. Correct assumption me thinks - although being no Volvo expert or up on modern systems, I'll leave it to some expert to see which part needs replacing. Replace wheel and aim to slow drive to my brothers general garage 1 mile away using foot/rear brake and 1st gear. Oops. Remembered its Auto and need to depress front brake to select drive. Gently touch brake and thankfully access drive. Make it to Garage but realise that as I left it standing on forecourt for nearly 5 minutes with engine running to prevent having to restart, it had 'tightened up the brake again and only just managed to move car to where Brother wanted it to wait until he looks at it this week. In summary, I'll post the end result as it seems that quite a few of these older XC90's have suffered same but with no answer available here. My guess is ?? Is there some electronic device to release pressure as i can't see it being mechanical - but we'll see.

 

Ok - update. ABS pump was taken off or looked at and the mechanics said that it looked like the O/S/F piston was sticking in the pump. They also said that the N/S/R was similar. That equates to how these diagonally actioned brakes work on opposite sides of car and F or B. That also tallied with my experience at times of pulling up and when reversing , I used to hear / feel a grabbing on N/S/R wheel. It never got too bad so didn't bother much about it. So at moment, it has freed off and I am monitoring it. The mechanics tell me that the pump can get overhauled rather than go to expense of a new pump. We'll see and hopefully whatever they've done will have smoothed them pistons out and stop them sticking.