Funny "thunk" in the back of my 2 door

[4.42doorrangie]

Hi all,

Bit of history 1976 2 door 33" tires 4.4 and now a maxi locker in the rear. I blew the diff some 6 weeks ago and this thunk was there then as well.... As i take off it sounds like the tailshaft is hitting the floor, a kind of hollow thunk sound. (obviously the tail shaft isnt hitting the floor it just sounds like it is) i wonder wether it would be the A frame ball joint or something else??

I have a new tail shaft in it so it shouldnt be that. bearing in the gearbox ???

Also does the diff housing rotate when taking off and could this be the cause???

Any one had this problem before any info would be GREAT!!!!!!

Simon

[long stroke]

Sounds like the ball joint or the diff to me;)

CHEERS TIM.

[Rangier Rover]

My ol 2 door has done it for years. It sounds like the A frame ball joint is ready to take leave. Also a snaped pin in diff spider can sound awfull before they spit. Try hand brake on and shift 1st to reverse and put some friction on clutch. This should not sound as bad. I asume the rear bushes are ok.
Cheers Tony.

[4.42doorrangie]

My ol 2 door has done it for years. It sounds like the A frame ball joint is ready to take leave. Also a snaped pin in diff spider can sound awfull before they spit. Try hand brake on and shift 1st to reverse and put some friction on clutch. This should not sound as bad. I asume the rear bushes are ok.
Cheers Tony.


I changed the ball joint around 1000k's ago but it has worked its way loose before. (no idea how) the diff is maxi drive, second hand though. I took my blown diff apart and the pin was in 5 different peices and the spider gears were all wandering around in the diff casing..... i hope its not that.... i want it to be something simpler like the ball joint.

Thanks

[350RRC]

The ball joint can become loose if the hole in the diff housing has become enlarged, which further enlarges the hole if not fixed.

If this is your prob you have probably noticed the nut (that was done up really tight and had a split pin put through it) can be moved with your fingers after a while.

What has happened is that the 'cone' of the ball joint has gone further down into the enlarged hole in the housing and you're tightening the nut and washer against the end of the thread, rather than the housing.

Try using an additional O/S washer so the tension from the nut and original washer is on the housing again. You might need two.

HTH, DL

[4.42doorrangie]

The ball joint can become loose if the hole in the diff housing has become enlarged, which further enlarges the hole if not fixed.

If this is your prob you have probably noticed the nut (that was done up really tight and had a split pin put through it) can be moved with your fingers after a while.

What has happened is that the 'cone' of the ball joint has gone further down into the enlarged hole in the housing and you're tightening the nut and washer against the end of the thread, rather than the housing.

Try using an additional O/S washer so the tension from the nut and original washer is on the housing again. You might need two.

HTH, DL

ill have a look at that tonight cheers for that..

[350RRC]

Hi 4.4,

By oversized washer I mean a washer that will go around the end of the tapered shaft that is supposed to be tight in the tapered hole in the diff housing.

A washer that just goes over the threaded bit and not the taper will only make the prob worse.

Hope you get the idea.

DL

[rovercare]

DL is spot on with the ball joint

It could also, be the trailing arm bush, bolt holes, they may be flogged, I didn;t check this sorry, but its an easy fix, just fit some snug washers, to the bolts and tack them in place

[4.42doorrangie]

Hi 4.4,

By oversized washer I mean a washer that will go around the end of the tapered shaft that is supposed to be tight in the tapered hole in the diff housing.

A washer that just goes over the threaded bit and not the taper will only make the prob worse.

Hope you get the idea.

DL


hey DL, so by washer around the tapered shaft you mean inside the tapered hole or will this washer sit on top of the diff casing or below the diff casing??? i understand that if the hole is enlarged it will allow it to move. Is there a way of enlarging the hole??? also i have never seen the bushes for the top of the A frame mount to the chassis?? could it be a combination of all these issues???

[4.42doorrangie]

DL is spot on with the ball joint

It could also, be the trailing arm bush, bolt holes, they may be flogged, I didn;t check this sorry, but its an easy fix, just fit some snug washers, to the bolts and tack them in place



hey matt, on the right side of the diff there is the bracket that holds the cover for the vaccum unit so i doubt it would be there. i didnt check the hole on the left, so you would fit a washer that is snug to the bolt and weld it to the outside of the trailing arm mounts??

[350RRC]

Hi 4.4,

The oversized washer goes under the housing.......between the nut, washer you already have and the housing. The purpose is act like a spacer to allow the tapered part of the ball joint to be pulled further down into the tapered hole by the existing nut and washer.

If the hole in the housing is worn the bottom part of the taper can protrude slightly through the bottom of the housing so the existing nut and washer is only pulling on the joint, instead of firmly pulling the taper into the matching taper in the housing.

That's why you need a washer with an inside diameter bigger than the bottom part of the tapered section above the thread.

DL

[rovercare]

hey matt, on the right side of the diff there is the bracket that holds the cover for the vaccum unit so i doubt it would be there. i didnt check the hole on the left, so you would fit a washer that is snug to the bolt and weld it to the outside of the trailing arm mounts??

That's correct

You really need to get someone to load it forward/revers while you look to identify it, they're all regular probs, could also be the A frame arm bushes