Bfii F6 Ute - Knock In The Rear

[Ralph Wiggum]

Could be yout tub liner striking the support braces or some thing between the braces and liners (ie a rock or pebble). My fuel flap door used to rattle in the clip the holds it shut until i tweaked it so it gripped the door tighter.

[tig]

Adrain,

Check the U bolts that secure the diff to the springs and the spring mounting bolts from and rear on each spring. They loosen up as the rubbers wear, this allows the diff to walk around on the springs and knock. The loose spring mounts/hangers allow the springs to slide sideways and knock on the hangers and mounts

My FG ute had U Bolts loose when I took it back to ford for diff clunk. They assumed it was the loose u bolts causing the clunk, unfortunately it wasn't that simple and it was the diff which I am waiting for replacement to come in. But yeah loose u bolts have been loose on a few FGs according to service guy so as a matter of course they should be checked.

[Adrian6T]

Well I got under there after work (I have a pit in the shed which makes it so much easier) and went to torque the U Bolts but unfortunately I did not have a deep 21mm socket. So I snooped around and found this loose first.

Yep, spare tyre was wobbling around.

Then I had a look at the suspension and noticed the rubbers looked like they were on there for 4 years.

Also that the rear brake lines are rubber. Aren't they supposed to be braided.

I then looked over my shoulder and noticed a bit of oil on the diff.

Fun times ahead.

[Adrian6T]

I change the diff oil in mine after about 8000k's

shut it up for a while.

Shut it up for a while? Which oil did you use?

[Guest]

castrol SAE something something with friction adative already mixed in, as opposed to the one where you buy it and add it seperatly

theres a thread on here somewhere about which oil to use

[Guest]

Go Royal Purple oil Adrian. There's a supplier off Dixon Rd called 'Auto Haus', just ask for Neil & tell him Dean with the XR6T sent you.

I'll be switching when I service the diff soon

[Guest SHADEY]

check hand brake adjustment ? if the rear hand brake shoes have been over adjusted it can cause them to grab & make clunking noise as they let go???

[cjsxrt]

hey champ when I got my ute home dad and I heard a knock in the rear end we found out it was the rear axle bolts loose lucky dad is a mechanic so it cost me any thing to fix it

[majin]

mine does sorta the same thing, slight knocking noise when you put your foot on the accelerator. ford said it was diff backlash, they replaced my lsd diff, and now it still does it......

dunno anymore

[Brandonn]

ask mitch in sunny coast quen thread * queensland he had this problem recently had heaps of dodgy answer from ford n every took ages to get fixed but was simple in he end cant remember exactly but pm him or something u can find him where I said ^^^