Transmission Slack/Backlash

Afternoon chaps

Just when I think im nearly one it pulls me back in!

Got some prettt horid backlash/tranny slack going on.

Take up is generally fine and smooth but if I let off in a low gear (mainly 1st & 2nd) theres a hefty clunk, metalic sounding. Does the same diff locked or not.

Better in higher gears but noticeable still but no noise.

So far checked -
A frame - very minor up/down play at the balljoint. Bushes have seen better days but minimal play
TX box rear output shaft had zero play last I checked a couple months back
Front prop -
UJs no play
Shaft spins about 1/4 way round before it stops
Rear prop -
Minor play in UJs - new ones on order
No turning play
Rear shafts & flanges have about 4k on them but look decent.
Rear diff is an Xcess 4x4 Ultra Build (2 - 3k on it maybe) so I dont suspect that.
Front diff has about 70k on it seems in good nick
Front pass side shaft & CV replaced with genuine a month ago
Not checked drivers side yet
Not checked front flanges yet either.

Any other ideas?

Aside from the backlash have you had any new or increase in vibration or humming noises?

dieseldog69 said:

Aside from the backlash have you had any new or increase in vibration or humming noises?

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Bit of a whurring noise (which i cannot record its too quiet) which ive had since the rear diff blew last summer which hasnt gotten louder or changed.

This is the extent of the front prop play.



No leaks from the TX or GB either.

bankz5152 said:

Bit of a whurring noise (which i cannot record its too quiet) which ive had since the rear diff blew last summer which hasnt gotten louder or changed.

This is the extent of the front prop play.



No leaks from the TX or GB either.

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That's quite normal.

What about the prop splines front and rear?

dieseldog69 said:

That's quite normal.

What about the prop splines front and rear?

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Yeah I thought so. 90 was the same.

Not checked the splines havnt the time this eve to drop props but i shall.

Im wondering if the DMF or clutch could be failing?

Didn't think it was that long ago that you had a new clutch & flywheel?

bankz5152 said:

Yeah I thought so. 90 was the same.

Not checked the splines havnt the time this eve to drop props but i shall.

Im wondering if the DMF or clutch could be failing?

Click to expand...

may i ask a daft question please , can u update the transfer case software on urs or isn’t it new enough , thks

A failing DMF tends to sound like Bricks in a cement mixer.

dieseldog69 said:

Didn't think it was that long ago that you had a new clutch & flywheel?

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Nope I thought they where going but turned out to me something else not sure what it was now.

Only mentioned it as the same thing happend with my 90. Master n slave went just shy of a year later the clutch went and the DMF wasnt far behind when removed.

Henry_b said:

A failing DMF tends to sound like Bricks in a cement mixer.

Click to expand...

Good to know. It isnt that just yet then haha

gstuart said:

may i ask a daft question please , can u update the transfer case software on urs or isn’t it new enough , thks

Click to expand...

No such trickery on TD5s!

So checking this morning

Rear drivers flange
- moves in and out 5mm - loosely
- less 1mm rotation

Rear pass flange
- 5mm in/out - tight
- no rotational play

Drivers front flange
- some rotational play
- see pics

Passenger front flange
- no play
- genuine new shaft and CV recently fitted

Front tx output
- no play

Front prop
- no play in splines
- no play in UJs

Front diff pinion -
No play

Drivers flange looked a lil dodgy so opened her up for some inspection. Lil rusty/old grease, shaft splines are a little pitted. There is some rotational play but not a huge amount.

Would it be worth fitting some HD flanges with the standard shafts? Take up some of the slack.

Changed the drivers side flange for a less worn (had no play at all LR flange) that came off the rear. Little better but the issue remains, managed to get a video and Im thinking it could be the clutch or output shaft.

Deffinate audible metalic knock when dipping the clutch

Mooore investigation. Jacked up the rear wheels and noticed some excess play in the rear prop. All the TX side bolts where very loose! Tightened up and the metalic clunk has gone, slack is better but still there.

As ive got a rear LSD that takes up a fair bit of slack! Serves me right for not checking...

I'd be more concerned with the state of your wheel bearings looking at those photos. You’ve had water in there at some point, so worth checking them.

A tiny bit of play in several components can add up to a lot of slack, especially in the front axle where you have more splines joints in the system.

I checked the front pass side bearing, which i degreased and regreased which was fine. Couldnt feel any play or harshness in the drivers side.

Rears have been off degreased, regreased again no play or harshness.

Though I will keep it in mind and overhaul the WB when ive some time off.