D4 unheard of brake issue?

[gavinwibrow]

Brakes on fire Mt Hotham to Dargo

We left Mt Hotham in the D4 with the brick in tow about Thursday lunchtime heading for Dargo, which is several hundred metres lower and includes about 50 km of gravel road travelling down the ridges in the top section.

I’d previously noticed an intermittent clatter/bang from under the lower front right when driving over rough stuff, but for the life of me could not see anything awry.
Anyway, after passing the gravel section and moving onto the steeper bitumen approaching Dargo, there was an intermittent see sawing type motion which I put down to the undulating road surface on the downhill side of the road affecting car and van. The road surface was obviously damaged from water erosion, and undercut in some sections.
Then my right hand front car tyre temperature monitor (Safety Dave’s brilliant system) started beeping with the temp quickly rising to 70 Celsius as I found a spot to pull over.
We found both front discs literally spouting fire like acetylene torches (no pics sorry, as I was a bit busy gently sprinkling water onto the wheels to put out the flames).
Eventually the brakes cooled and we very carefully proceeded on downhill, this time at a walking pace with engine braking supported by caravan brakes (the latter got warm but nothing like the front discs and being set properly so they activated just before the car brakes).
By the time we pulled in to the caravan park at Dargo, having had to apply the car brakes a couple of times, there was a distinct grinding noise.
To cut a long story short, and after checking many places and finally getting a car booking at Gippsland LR in Traralgon for middle of the following week, we stayed at Dargo over the weekend. On the Monday we had a slow trip in a tilt truck with D4 on top and caravan towed behind. Thank goodness for RACWA Ultimate which hopefully should cover most of the tow and accommodation costs.
At Gippsland LR we were advised that initial inspection showed there was a bolt missing from the front LHS brakes, and they were even wondered if it had even been fitted. They had never heard of one of these bolts breaking or coming undone! I’m bringing some of the replaced bits home for further investigation.

See the hole under the wire just south east of the yellow tie/clip/ in the attached pic

After a couple of false starts, the new ordered parts finally arrived (new discs pads and callipers) and we then had to wait for a further slot in the workshop. Once finally in the workshop and the brakes dismantled, a further defective part was identified with more delay while a new one was ordered. I don’t understand why I can order a part from Melbourne and have it in Perth next day whereas this example was ordered on Thursday, but didn’t arrive from the 150 km journey to Traralgon until the following Monday.

So after a lost full fortnight we finally got our car back and took off heading west for home with no further problems arising.

[Tombie]

Not an unheard of occurrence, several posts of people losing one of those bolts. Always attributed to a brake pad change or similar at some point prior.

What pads have you been running in that vehicle?

[gavinwibrow]

Not an unheard of occurrence, several posts of people losing one of those bolts. Always attributed to a brake pad change or similar at some point prior.

What pads have you been running in that vehicle?

Put new akabonos? on the fronts just a short while before heading east - I've actually brought the pads home with me, but don't know if they are re-useable in any form.

[Tombie]

I suggest you give the wheel(s) a good checking over, firstly because that calliper has likely carved a groove in the wheel and secondly because that heat may have done more damage to rim and tyre.

[gavinwibrow]

I suggest you give the wheel(s) a good checking over, firstly because that calliper has likely carved a groove in the wheel and secondly because that heat may have done more damage to rim and tyre.

Thanks Mike. I'll get Dazza to do a proper inspection now that I'm back in the west. 100K/7 year service about to be done!!

I'd be horribly disappointed with Gippsland LR if there is any such damage missed from their inspections, and apart from their overworked time delay, I can't fault their efforts to date.

[Eric SDV6SE]

Gav, those bolts are supposed to be torqued (I forget thr value, I think it's around 60Nm. Threads to be dry and clean. I have personally never seen these come undone, and i always double check all bolts i do up. Glad you made it back safe, like tombie says, get that wheel checked or put the spare on, you've likely got a nice deep stress raiser in that rh front wheel, and I'd not like to travelling at 80-90kmh towing speeds with a fully loaded car and van and that letting go.

I'd also be checking the hub bearing just for piece of mind.

[kelvo]

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Gav, those bolts are supposed to be torqued (I forget thr value, I think it's around 60Nm. Threads to be dry and clean. I have personally never seen these come undone, and i always double check all bolts i do up. Glad you made it back safe, like tombie says, get that wheel checked or put the spare on, you've likely got a nice deep stress raiser in that rh front wheel, and I'd not like to travelling at 80-90kmh towing speeds with a fully loaded car and van and that letting go.

I'd also be checking the hub bearing just for piece of mind.

275Nm for the carrier to hub bolts.

[DiscoJeffster]

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275Nm for the carrier to hub bolts.

just a little off. Maybe they listened to Eric’s advice in the first place and that’s why it fell off??

[discorevy]

Bummer
I don't know if the Discs were changed along with the Akebono pads, but that's the only time those carrier bolts need to come out.
They are not normally touched for just a pad change.

along with the others, I'd also suggest checking out the inner rim as it looks like it has been rubbing on the calliper in the pic.

[Eric SDV6SE]

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275Nm for the carrier to hub bolts.

Yes agreed, my bad, i looked at the photo on my phone and only saw the caliper slide bolts.