SLROC Forum

Hi Guys
Hoping for some pointers.. Lost drive today just as I was taking of from traffic lights, just like it jumped out of gear...clunk...
Eventually was only able to move when I selected Low Range Diff Lock... Drove 2 miles to house and parked...

History..
About two years ago  I swapped out the old gear box for a discovery one. ( the mainshaft spline had stripped )

I am by no means an expert but if it was the shaft again surely it would not drive at all...

Its lying at house so have not had a chance to jack it up , just hoping someone out there might have some pointers...
Thanks
james

 Hi
 Sounds like either a hub drive flange spline failure or a half shaft spline failure. If you remove the plastic cover @ each hub you should see rust or metal debris at the defective hub. Failing that if you jack up each wheel in turn you should be able to identify the broken half shaft if that is the defect instead. It is worth checking all the hubs, if one is worn then the others are likely to be suspect.

Hi
Thanks for that, I will be having a look this weekend so will update what I find 
j

Yeah you were spot on , turned out to be the N/S/F driving flange..
While checking the rest I found the o/s/f driving flange bolts were in a state 3 broken and just sitting in...rest a bit loose...
so rather than try and get the broken bolts out was thinking of replacing hub assembly...
anyone have any tips here
cheers

 Hi Banzia
 Based on your reply can I suggest that you make a careful inspection of the splines on the outer end of the half shafts.
 The splines should be square in section, it is common for the splines to wear & become tapered where they enter the drive flanges, eventually stripping completely again resulting in loss of drive. This in turn would damage your nice new drive flanges. The wear I refer to will be obvious if you look @ the section of spline that has not been in the flange. If you try a new flange on the shaft & try to rotate it you will see the excess play I refer to. I suspect you have had a lot of back-lash in the drive train for some time. I would check all the half shafts for this wear pattern, do the job right, do it once!
 Regards

Hi aqms

Thanks again, because of the weather I cant get near it however Have been reading your replies..

When you say half shaft play I take it you are meaning the cv joint plines that go into the driving flange ?

I have noticed when the prop shaft was off awhile ago that there does seem to be quite a bit of back lash on the front diff...  I dont think this can be adjusted on an old axle and new ones are a fortune...
james

Hi
 Yes, I am referring to the play between the drive shaft outer splines & the drive flange itself. The splines on both components do wear through time thus allowing this free play, if you look at the splines on the drive shaft they should be square in section & should be a close fit in the corresponding splines in the drive flange If you clean up both items & then offer them up together then attempt to rotate the flange you will immediately see if there is excessive wear. What normally happens is that the splines on the shaft will strip or round off resulting in loss of drive. I suggest you borrow a new flange & compare the two. Sadly changing the flange only is usually a very temporary repair as the worn shaft will damage the nice new flange. The play you refer to in the diff pinion flange is likely to be the sum of the wear in both your front drive flanges etc unless you are very unlucky. I would be very interested to hear what progress you make.
 I suggest you make a similar examination of your rear hubs etc.
 Regards

Hi

Sorry for the delay in getting back to you all with what I eventually did to resolve the no drive scenario... Broke my collar bone after falling off motorbike...

I could have just changed the drive flange and it would probably have been mobile but following the advice aqms987 I decided to do a more indepth fix..

After stripping the N/S/F flange off I found that the spines were in a terrible state, also the splines on the cv joint were really bad as well..

So i decided to fit new halfshafts, cv joint and new flanges to both sides... If I had the money I would have changed out the diff too.... however the backlash is much less now that all the rest of the drive has been replace..

While I was at it I replaced the disc backplates fitted new pads and regreased all the hub bearings

thanks again for the help and motivation to do the job right
james

 Sorry about the collar bone, I do not remember suggesting that!
 Glad you found the advice of use, I suspect that you will have much less slack in the transmission now. Once your wallet gets out of intensive care you might find it worthwhile having a close look @ the rear hubs, flanges etc, could save you a degree of embarrassment!
 Regards
 Allan