Play in drivetrain evidenced by clunk

Hi, I would much appreciate your thoughts on diagnosing the source cause of a clunk sound I get about 1 second after I shift into every manual gear (both high and Low mode). I appears there is play somewhere in the drivetrain. When I jack up the passenger side of the front axle, I have to turn the wheel 2 1/2 inches before the drivetrain engages and starts turning the front prop shaft. It also clunks when I apply and release the gas peddle. I paid $270 to have a shop diagnose it (they specialize in Land Rovers). After only 10 minutes, the technician estimated it was the transmission until I showed them a video of the front axle side of the propeller shaft making a clunk when I popped the clutch. You would think the clunk was coming from the the U-Joint, but the mystery is that it did not move a bit. A week later I produced and showed a video to the manager and he suggested just replacing whole prop shaft which didn’t make sense to me because the only part on the shaft that could cause that sound would be the u-joint and it is clear from the video that there was no u-joint movement. The clunk can be heard from both the front axle and transfer case sides of the prop shaft. Unfortunately, I am unable to get the video to load on this site because it has a .mov extension. However, I have attached a shot of the showing the transfer case side of the prop shaft.

rklemm said:

Hi, I would much appreciate your thoughts on diagnosing the source cause of a clunk sound I get about 1 second after I shift into every manual gear (both high and Low mode). I appears there is play somewhere in the drivetrain. When I jack up the passenger side of the front axle, I have to turn the wheel 2 1/2 inches before the drivetrain engages and starts turning the front prop shaft. It also clunks when I apply and release the gas peddle. I paid $270 to have a shop diagnose it (they specialize in Land Rovers). After only 10 minutes, the technician estimated it was the transmission until I showed them a video of the front axle side of the propeller shaft making a clunk when I popped the clutch. You would think the clunk was coming from the the U-Joint, but the mystery is that it did not move a bit. A week later I produced and showed a video to the manager and he suggested just replacing whole prop shaft which didn’t make sense to me because the only part on the shaft that could cause that sound would be the u-joint and it is clear from the video that there was no u-joint movement. The clunk can be heard from both the front axle and transfer case sides of the prop shaft. Unfortunately, I am unable to get the video to load on this site because it has a .mov extension. However, I have attached a shot of the showing the transfer case side of the prop shaft.

Click to expand...

To make a video work on here, you need to make it into a Youtube and then put up a link to it.
My advice is to remove the propshaft, to prove it isn't it then see how much play there is between the propshaft flange and the rest of the differential.
If there is no problem there, then do the same at the other end of the propshaft to see if there is too much play in the transfer box.
Have you checked out the rear end of the transmission?
When I had this sort of problem, at the rear it turned out to be a loose nut securing the pinion drive.

Thank you for the Youtube idea! I will learn how to make a movie on youtube and get that done. WRT the prop shaft, once I remove it, how will I recreate the clunking sound without the prop shaft being hooked up?

Please see the youtube video at the link below to see what is happening.

The way the power is delivered to the wheels needs to be understood so you can giagnose this (wierd) problem.
The engine turns the flywheel which in turn spins the drive plate of the clutch (unless you've pressed the pedal and it is disengaged).
This rotation spins the input shaft of the gearbox (R380) and if 'in gear' spins the output shaft.
The output or the R380 spins the input of the LT230 (transfer box) which in turn has 2 gears (high and low) and a neutral.
The transfer box incorporated a differential which is normally unlocked and can be locked.

When unlocked drive is present on the least resistive output flange (front or back) - ie if you lift the whole front axle off the ground the front wheels will turn and the backs won't. This also applies if you lift the back up, ie the back wheels would get 'all' the drive.
When 'locked' the LT230 will deliver drive to both flanges equally ie it drive both axles irrespective of the presented load.

rklemm said:

WRT the prop shaft, once I remove it, how will I recreate the clunking sound without the prop shaft being hooked up?

Click to expand...

To 'test' the drive shaft you can remove it and see if the 'clunk still happens.
With the front shaft off and the LT230 locked you will have a rear wheel drive car.
With the LT230 unlocked you will have no motion as the front flange will spin feely.
The same applies to the rear shaft ...

It looks (in the video) like the LT230 is 'wound up', ie that you have been driving around with the transfer box locked.
This puts a huge amount of strain on its internals as when negotiating a bend on a non-slippery surface, the rear of the car is travelling faster than the front.
It's a good way to strip the gears or snap the shafts in the LT230

Ouch, yep totally agree, it is coming from the transfer box. as @miktdish said.
If difflock is engaged there ought to be a light on the instrument panel telling you this. Maybe it has bust, anyway, if you are having trouble disengaging it, and you do not have a copy of the owner's manual, push the lever over to disengage it while driving a very short distance in reverse, because they can "stick in".
If that doesn't work, get back on to us.