Transfer case whine

[92a]

Hi , after years off the road I have finally got the “series “ back together, The transfer box was full of water so was rebuilt with EAC parts and a new genuine output shaft  and it’s associated gear ( blue box but old stock) along with a used intermediate gear as mine had rusted solid and turned the shaft in the casing , it’s got an Ashcroft 5 speed kit and input gear and it’s really noisy now ☹️, I’ve checked the intermediate gear play and it’s minimal , the preload on output shaft was set up as per green book ? The new intermediate shaft did not have any lateral movement in the casing , I’ve driven a defender for years since but sure it wasn’t as bad as this before, any ideas ? Angus 

[lo-fi]

Ashcroft will tell you that some of the cheaper gears available haven't had the teeth "crowned" and will be noisy. I suspect that may be the case here. Find a section on this in this page: https://khkgears.net/new/gear_knowledge/gear_technical_reference/involute_gear_profile.html

The "used" gear may well have worn oddly and possibly be the source of the noise too. 

[92a]

Guess I have to try this one ? I can’t find any numbers and the main box has had a bit welded in at some time , came out of a series 2a but it has series 3 bell housing, 

[Gazzar]

!!

[Gazzar]

Is that a British Leyland logo on the main box? 

[92a]

Yes , I’ve not seen a series main box for years so not sure what markings it should have , it’s also got a steel drain plug in the transfer box cover rather than a brass one 

[Arjan]

That looks very much a Series III box to me

 

[92a]

I’m just taking it apart now, so far so good,  intermediate shaft thrust washers still had grease behind  them so hoping someone has been in here recently or it’s not been in the car long before it came out , this is the logo on the main box , not sure if that helps date it ? 

[Jon White]

That’s not a five speed gearbox that’s a standard series 4 speed.

compared to a defender Transfer box a series one will always be noisy. It was one of the reasons I too ther series transfer box out of mine and fitted an LT230 

[92a]

The 5speed is still in place I only pulled the transfer case off and this one  was the donor for the replacement transfer box ,it seems to have been reconditioned and  it also yielded an overdrive with good splines and that’s destined for the “For Sale” pages as soon as I remember where I put the linkage , the replacement transfer box seems quieter too 😃

[92a]

Hi, sorry to revive this but I’m still hoping to get my transfer case noise down to an acceptable level , I have put another transfer box in and it’s a bit better but noticed how much the intermediate shaft thrust washers shims had worn in the 100 or so miles before the change over , I’m sure I read that “if the castle nut on the output shaft is not torqued correctly it can make a good gearbox noisy “ I wonder if I need to put more preload on the Ashcroft input gear ( the “PTO” cover they supply in the kit would need a skim to do this ) If any one has any ideas I’d love to hear them ? Or a really good series transfer case ? Thanks Angus 

[bill.b]

Did you get to the bottom of this? I have just put one of these 5 speed kits on an r380 and I have a similar problem at low speed. 
cheers 

[92a]

The second transfer box is still the same noise wise as when it went in, I did try a thinner gasket on the PTO cover to increase the preload and this may have helped but it’s still noisy, I am not sure the  outer race (in the PTO cover )  was replaced and want to replace it myself so I know it’s been done , just in case this is causing the noise but  I have managed to get both a genuine intermediate gear and high speed gear from Italy and hope to rebuild it again with these and the last thrust washers I’ve had squirrelled away 

[Snagger]

The faces of those intermediate shaft bushes look good to me - slight polishing from where the roller bearing cages have run against them, but nothing from the gear cluster.