Thread: 101 Front diff

One of the main reasons the standard tailshaft rumbles/buzz/rattles on the float going down a hillis the high speed the thing spins at due to low diff ratios and the middle of the tailshaft having to go though four speed variations per revolution with the tailshaft tube and splines having mass.
does this matter at the end of the day and the answer is no.
It doesnt cause any major problems other than needing to grease frequenty and keep tight various bolts etc of the front drive line.
high unijoint wear on the standard shaft is caused by high rotational shaft speeds and high operating angles.
standard 101 tail shafts are cheap and easy to replace uni joints on.
Series three and other model landrover shafts can easily be chopped and fitted as a replacement at low cost.

things which reduce the tail shaft buzz of a 101 is.
1/ fit a overdrive as you can power on for longer going down a hill for longer and not get into the over run tailshaft buzz situation.
2/ have a tailshaft in good nick.
3/ have a light weight tail shaft..ie not heavy duty as it will have less inertia and allow a higher speed before the tail shaft buzz comes in.
4/ when setting up the diff pinion go for the maximum crown wheel back lash of 12 thou as this gives the tailshaft room to move when it buzzes with out a load on it.
The pinion hitting the ring gear quickly front one side of the gear to the other is what really causes the noise due to the four speed differences per revolution partly caused by high speed inertia.
I tighten my pinion to crown wheel clearence to 4 thou thinking I was doing the right thing and made it slightly worse.
5/ grease the spline before a long trip as the grease acts as a shock asorber in the splines and lessons the noise.
On a standard tailshaft set up in good condition the noise doesnt matter a stuff to the vehicle and it is only the driver which has a problem with it and non 101 informed mechanics who think there is some wrong with the drive line.

If i was going to stop the 101 tailshaft buzz( I am not going to as it is not worth it)
I would try some sort of cush drive.( rubber donut on a standard shaft and uni ,s)
It wouldnt stop the buzz in the real world, but would reduce the noise as the pinion rattles against the ring gear.
higher diff ratios would very greatly help, but a 4.6 litre motor would be needed for that.
A two ended double cardon or CV tail shaft would work , but the short life and high costs for the 101 application rules it out for me.

Hello! I owned a 101 for several years in the UK, and yup I had the same noise from the front prop. 1, Change the 5.9 to 1 crown and pinnion for 4.7 to 1 c&p found in Ser 3 rear axle (this rases the gearing and slows the props which helped mine and was needed for the impending diesel conversion). 2, Change the 4 sp box for a 5 sp Santana Box (early V8 110). This pushes the transfer box position back and eliminates the noise (or it did when I shoe horned a 6cyl 6ltr Nissan diesel into mine) and 3, make up a CV jointed front prop. (I did using early Rangie cv's which worked well untill the diesel tore them appart.. (very messy))! Do not cut the axle and tip the diff as Salisbury diffs do not like to run with a dry pinnion bearing! Simon!

I agree with all Ron has said HOWEVER Landrover installed a double carden on the gearbox end of the front driveshaft on the Series 3 Stage 1 and much later in the Discovery 2 - obviously done for a reason - reduce vibration.

My driveshaft is rubber filled and takes a lot of the vibration out - can still feel it and now only rarely hear it over the 101 already loud noises.

I think the solution is DC, rubber filled shaft, lower drivers side engine gearbox mounts, rotate front diff housing (oil level needs adjustment to prevent dry pinion bearings) if you do not want to change diff ratios. I have calculated drive shaft RPMS at different speeds and it is only about 10% more in a 101 over other landies and about the same where other landies are at higher speeds (120-130kph).

Moving the gearbox back will cause issues with the rear drive shaft as it is already steeper and shorter than the front shaft (still not sure why the noise comes form the front and not the rear).

Garry

Garry

Thanks for all the input, good point about running the pinion bearing dry with a changed angle on the diff Simon.
Guess I will get it back together and try a few things from there.
I will try both the DC and standard front shaft to see if there is any difference.
Dropping the RHS of the motor gearbox sound like a feasible option.

Originally Posted by garrycol

Why bother - two trips offroad and it will be just as crappy as it was before and the dirt never comes off. I completely repainted the whole underside of my 101 just before I put it back on the road and now 8 months later it is just as crappy as it was and it gets an underbody wash after each trip offroad.

At least I will know what is under the crap I put on it, good chance to check everything out, already found a few issues. Also getting rid of the silver underbelly is a priority plus I have a bit of time on my hands,

Peter

Hi all, I recently sold my 101 and supply trailer to a fellow here in Adelaide. I found that the propshaft vibration could be limited if the pinion nut was tightened a flat or two ( no more) I never worried too much about the racket it made though and I have driven the vehicle on many extended trips to the Flinders Ranges and interstate without it ever getting any worse. Most drivers just get very good at balancing the engine load on the drive line. NOW CHAPS.... DO ANY OF YOU KNOW WHERE I MIGHT FIND A SET OF 101 AXLE ASSYS COMPLETE OR IN OTHER WORDS A UNIT BEING WRECKED SOMEWHERE ? cheers Dave

Originally Posted by R12 Krad

DO ANY OF YOU KNOW WHERE I MIGHT FIND A SET OF 101 AXLE ASSYS COMPLETE OR IN OTHER WORDS A UNIT BEING WRECKED SOMEWHERE ? cheers Dave

About the only place I can think of is Land Rover 101 - British 4wd Imports - Home Page

Garry