Transfer Box Knock When In Diff Lock?

Hi All,

Had New/Recon Transfer Box fitted and went for a run, all good while driving normal hi range. Wanted to check Diff Lock so took it to a car park, engaged low diff lock seemed ok, hi diff lock ok, both in straight line driving. Attempted to put back into just hi range and struggled, light stayed on, then realised need to set off for it to switch off. Light off and turned left slightly clunking from transfer box/forward, Noooooooo! Waited a few minutes then tried again, all ok in Hi range.
Headed straight to garage for reassurance. Mechanic took for test drive with me in it and all seemed ok on hi range. He struggled to put in low range diflock and then hi range diflock, all seemed ok, no sign of knock. Put back into Hi range to set off and knocking appeared when he turned, almost as if transfer box/prop “winding up?” Stopped re-engaged hi and all ok, headed back to garage. "Yes an issue, never had problems with replacement transfer boxes in past, Too busy at moment so they will have a look in a couple of weeks, but been told shouldn’t be a problem driving normally?"

Worried they are going to try and blame something else(more money) or is it the new/recon transfer box to blame? Since then I’ve nipped on to a car park in normal hi range and put full left and then right steering lock on no knocking so CV joints and drive train seem ok.

Also, just found the gear change support bracket(UCB500150) on the floor 2nd row. This wouldn’t be causing any issues, plan to get them to refit when I head back in 2 weeks?

Apologies for “war and peace”, but trying to give you as much info to help in your advice/observations.

Thanks

So you took it to a hard surface car park for these tests ?
You say in your report " almost as if transfer box/prop is winding up " In other words you are getting transmission wind up.
Well that is exactly what you are getting if you are in diff lock [ high or low range ] when turning on a hard surface. Something the Land Rover manual says you should not do.
When you wind up the transmission on a hard surface there is only a few ways the wind up can release, worst case while unlikely is something busts. Most likely one or more of the tyres skids/slips for a moment resulting in a clonk through the drive train. Followed by more clonks should you keep driving.
While doing the above and you move the lever out of lock [ the actual lock only works when it wants to and is not directly linked to stick ] it may then suddenly release under wind up load with quite a clunk and then go quite.
Test [ exercise ] your lock while on a slippery surface, nearside wheels on a grass verge will do.

tottot said:

So you took it to a hard surface car park for these tests ?
You say in your report " almost as if transfer box/prop is winding up " In other words you are getting transmission wind up.
Well that is exactly what you are getting if you are in diff lock [ high or low range ] when turning on a hard surface. Something the Land Rover manual says you should not do.
When you wind up the transmission on a hard surface there is only a few ways the wind up can release, worst case while unlikely is something busts. Most likely one or more of the tyres skids/slips for a moment resulting in a clonk through the drive train. Followed by more clonks should you keep driving.
While doing the above and you move the lever out of lock [ the actual lock only works when it wants to and is not directly linked to stick ] it may then suddenly release under wind up load with quite a clunk and then go quite.
Test [ exercise ] your lock while on a slippery surface, nearside wheels on a grass verge will do.

Click to expand...

Thanks for quick response, realise hard surface is not place to use diff lock, just rolled Landy forward very slowly with diff on in straight line to test and after disengaging diff, knock happened when slight turn of wheel to left while back in high range. Would expect the mechanic to know how to use diff lock, but he agreed there was an issue, which makes me even more concerned that the landy specialist garage doesn't know how transfer box/diff lock works!
Will give it another go as suggested on grass verge, weather will definitely help with "slippery surface!" Thanks again

Ever since the Range Rover came on the market in 1970 the so called permanent four wheel system has caused more confusion among drivers/owners than any other item I recon.
Given that your box is a recon things can be a bit stiff to start. When you drive along a grass verge [ one with a bit of a curve would be good ] and then move lever to lock it may take a bit before it goes in and the light comes on, this would be normal. The same goes for when you move to the out position. Hold the lever there until it goes out. Sometimes they can be reluctant to come out of lock, reversing back some will get it to come out. There should be no big clunks as you do this on the wet grass.

tottot said:

Ever since the Range Rover came on the market in 1970 the so called permanent four wheel system has caused more confusion among drivers/owners than any other item I recon.
Given that your box is a recon things can be a bit stiff to start. When you drive along a grass verge [ one with a bit of a curve would be good ] and then move lever to lock it may take a bit before it goes in and the light comes on, this would be normal. The same goes for when you move to the out position. Hold the lever there until it goes out. Sometimes they can be reluctant to come out of lock, reversing back some will get it to come out. There should be no big clunks as you do this on the wet grass.

Click to expand...

Update - found an unmade/muddy car park and tried diff lock out, worked perfectly. Had to do as you suggested, reverse to get it out of diff lock once, but all good. Thanks for help on this, much appreciated.

Sounds like it is working as it should then.