Rear end knocking

someguy · Post by **someguy** » Tue Dec 22, 2009 5:58 pm

Hi all.

over the past few months my L series has developed a knocking noise that seems to be coming from either the left rear drum or bushes.

It only knocks when braking but is starting to get on my nerves and I want to get it fixed.

has anyone had the same issue. if so what was it.

I am thinking maybe the drum is warped?

Thanks

H-top · Post by **H-top** » Tue Dec 22, 2009 6:49 pm

Diff bush?

shuffbag · Post by **shuffbag** » Tue Dec 22, 2009 6:50 pm

yeah may not be... but i would check the pins that keep the drum shoes in place.

i lost some when i had the wagon, if your car feels like the brakes hang abit this could be your problem. if the brakes lock on its more obvious

other than that have you checked every thing back there is tight? jack the rear up, try to move the wheel in all directions?

username · Post by **username** » Tue Dec 22, 2009 7:30 pm

i had it, just ingnored it till it went away. you may want to try a different approach though

Post by **TOONGA** » Tue Dec 22, 2009 7:45 pm

1 your brakes need adjusting (even with an auto ajuster they can still need ajusting)

2 the drums are full of a mixture of brake dust and brake fluid they need to be cleaned out then adjusted

both of these will cause your brake pads to slip in the drum causing that ever present knocking noise

the other option is to find the elusive rear disc brake end for your car and install it no more knocking noise

TOONGA

someguy · Post by **someguy** » Tue Dec 22, 2009 8:41 pm

shuffbag wrote:yeah may not be... but i would check the pins that keep the drum shoes in place.

i lost some when i had the wagon, if your car feels like the brakes hang abit this could be your problem. if the brakes lock on its more obvious

other than that have you checked every thing back there is tight? jack the rear up, try to move the wheel in all directions?

Yeah, I have tried making sure everything is tight back there.

As one of the previous posters mentioned I haven't checked the diff bushes, will do tomorrow. As I mentioned in the OP it may not be the drums its just coming from that general area.

If the diff bushes are fine I will book it in with the local brake specialist to get the drums cleaned out & adjusted. (I don't have the 36mm socket to remove the center bolt from the hubs or a breaker bar, if I did I would do it myself)

AlpineRaven · Post by **AlpineRaven** » Tue Dec 22, 2009 10:03 pm

give yourself a go, it could be one of the joints that is worn out, grab WD40 and spray one joint a time (ie. one joint per day) and listen the noise and see if it goes away and narrow it down to the point.
Cheers
AP

Post by **TOONGA** » Wed Dec 23, 2009 8:41 am

A 3/4" socket set, ratchet and breaker bar can be purchased new for under 150 dollars or even a 36 mm spanner (any of this is even cheaper second hand) and while that might seem expensive being able to do your own brakes, change CVs and anything else that needs the 36mm socket, automatically cuts down trips to mechanics and brake specialists (and cuts down the costs involved) make it a Christmas pressie to yourself

have a good holiday

TOONGA

Morcs · Post by **Morcs** » Wed Dec 23, 2009 9:47 am

Check loosnes across the diff (axle to axle) my brumby has this. (Mine has Vlsd though)

Also check the little spigot axle that connects the cv to the drum. (Cv moves around a little)

Check the cross member itself for cracks etc around diff carrier (gusset)

The brumby had this also untill i welded it up.

Mine is an awd may not be relevant but worth a look

someguy · Post by **someguy** » Wed Dec 23, 2009 10:00 am

Morcs wrote:Check loosnes across the diff (axle to axle) my brumby has this. (Mine has Vlsd though)

Also check the little spigot axle that connects the cv to the drum. (Cv moves around a little)

Check the cross member itself for cracks etc around diff carrier (gusset)

The brumby had this also untill i welded it up.

Mine is an awd may not be relevant but worth a look

Thanks for the tips.

Its 42 degrees here today so I think I will leave it until it cools down tomorrow but I will let you all know what I find

YouTube · Post by **El_Freddo** » Wed Dec 23, 2009 10:27 pm

Mine was still there even when the rear discs went in. Turns out it was the rear shocks, they were *slightly* shot. A second hand set did the job, swapping the thumping/knocking for a squeak from one of the lower rubbers - I can live with that.

Cheers

Bennie

phillatdarwin · Post by **phillatdarwin** » Fri Dec 25, 2009 2:58 pm

mine has a knock in it and it was the diff bush

someguy · Post by **someguy** » Fri Jan 01, 2010 11:37 am

Ok, got the drums cleaned out and adjusted. which didn't do anything so that rules out the drums. (It was still good I got them cleaned as around half of goolwa beach came pooring out when they were cracked open :P)

Which means it must be the diff bush.

Does anyone know the part number/code so I can go down to repco and get a new one.

Thanks

YouTube · Post by **El_Freddo** » Sat Jan 02, 2010 9:27 pm

Before you go getting a new bush drop the diff out along with the two rear shafts and half of the prop shaft - you can still safely and legally drive around without the rear diff in the subi. I've done this a few time with many k's covered and no problems until I tried to go offroad one day forgetting I didn't have the rear diff in

Once its out go for a drive and listen for the noise. If its still there its not the diff bush.

Cheers

Bennie

someguy · Post by **someguy** » Sun Jan 03, 2010 1:26 pm

El_Freddo wrote:Before you go getting a new bush drop the diff out along with the two rear shafts and half of the prop shaft - you can still safely and legally drive around without the rear diff in the subi. I've done this a few time with many k's covered and no problems until I tried to go offroad one day forgetting I didn't have the rear diff in

Once its out go for a drive and listen for the noise. If its still there its not the diff bush.

Cheers

Bennie

I am not that confident in my mechanical skills just yet haha + I had most of my tools knocked off the other week (forgot to lock the shed when I went out overnight)

If it is the diff bush what do you guys think would be a reasonable price for a mechanic to charge to do the job (inc cost of the parts)

I heard from a mate that he paid $450 to get the diff bush replaced on his BA falcon. (seems a bit high?)

AndrewT · Post by **AndrewT** » Sun Jan 03, 2010 2:05 pm

someguy wrote: I heard from a mate that he paid $450 to get the diff bush replaced on his BA falcon. (seems a bit high?)

bahaha that's funny.

Diff bush on an L series is just a small thing. Not sure exactly how much they cost new but it's probably less than 50 bucks. It's quite hard to find them off the shelf though. Try BlackBox Motorsports advertised on this forum.