*CLUNK* in diff or g/box? Whining after 4wd engaged?

[BennyWA]

Howdy all, just wondering if anybody has been lucky enough to have a clunking sound come from the diff or gearbox , usually happens on takeoff and mostly after a slightly hard depression of the brake pedal.... seems to be a fair bit of play in it....hope it doesn't cost much!!!
Also, after engaging 4WD the drivetrain makes a whining noise for 10 k's or so..
Any ideas?
Regards, Ben

[Buzz]

Get your rear diff checked, sounds like spider gears are badly worn.

"....hope it doesn't cost much!!!" - depends what it turns out to be, maybe change your surname to Dover

If you do need the rear diff rebuilt way up that cost with putting lockers in may be the most cost effective way to get them.

[Steve F]

I think the whining is pretty much normal, the gears in the transfercase are still 'meshed together' and whine as the speed rises. Once they loosen up again and 'slacken off' the whining goes away. At least thats my theory on it as my XJ does the same and has since I've owned it (35,000km now on 105,000km). I notice it particulary at higher speeds like above 70kmh and when accelerating hard, again it goes after a few KM's and wont come back until 4WD (low range in particular) has been used for a while.

The clunk can be the slipyoke on the rear driveshaft. Drop the shaft and give the joint a clean and a grease, I think this is pretty common as well

Cheers
Steve

[Moses]

have you tried turning the sterio up i find that this will fix most problems and if not some bigger speakers will and thats alot cheaper than any mechanical fix

[pzver]

Originally Posted by XJ Moses

have you tried turning the sterio up i find that this will fix most problems and if not some bigger speakers will and thats alot cheaper than any mechanical fix

I like this idea very much.

[jake]

rear brakes are out of adjustment, i had the same sound.

[jake]

they need to be adjusted firmer against the drum