Thread: 101 Front Driveshafts

Thanks Ron - good information - I am beginning to find I am getting more out of you and the other 101 owners in Australia than all of the 101 owners in the UK.

I agree Garry, perhaps user 101Ron should be modified to Yoda101Oz!

I will be interested to see how Peter P's new drive shaft works in his truck when it gets onto the road.

Probably not as interested as I am. Hope it cures the issue as I am told it will. I have also been told the double cardin shaft should work but when they stuff up they do it in a big way.
Very interesting how the 4 thou clearance in Rons diff changed the harmonics. Possibly more effect than cause?
I have some thoughts on this issue overall. but will reserve comments until CanDo can do a few k's. May even make it to Canungra.

Peter

Ok I hope this post isn't too irrelevant but I have a Stage 1 that originally came with a double cardan joint.
I replaced the double cardan with a standard Rover type shaft that was the right length, for ages I chased a rumble that obviously related to the tailshaft sadly I couldnt fix it with balancing or anything else.
I had a new clutch put in in Geraldton by Wyatts and they put the shaft back on with the spline at the transfer case end.
Problem gone its not perfect but its a as good as any Stage 1 I have driven.

The 101 does have the splines at the tfr case end - indeed I am thinking of changing it around to see if anything changes if I put it at the diff end - I do not think so but who knows.

Unfortunately everyone in the 101 community seems to have an idea on what the problem is and how to fix it - however I have not come across anyone who actually has fixed it and this is after nearly 40 years after the 101 was designed.

If it was just the front driveshaft - the rear driveshaft would be causing issues as well. When I ask the question why the rear driveshaft has no issues on the UK forums the question is just ignored - the only one to even discuss it has been Yoda101Oz.

I have tried one approach that has been not been successful - though the rubber damper seems to have helped a little. It will be interesting to see how Peter's new shaft works.

Garry

To do some other work on my 101, I have removed my rear driveshaft. I then decided to see what impact this would have on the 101 rumble. I have previously driven the 101 with the front driveshaft removed - no rumble but increased drivetrain backlash.

When driving with the rear shaft removed there was virtually no drivetrain backlash at all, however the rumble was substantially increased and started at a much lower speed. Normally in my 101 the rumble is not heard below 80kph and is very soft increasing in volume as speed increases. On this test run, the rumble started much lower at 60 kph and was very loud.

So in some way the rear driveshaft has an impact on reducing the front rumble - not sure why this should be so though.

Garry

Garry,

How was it to drive with the front shaft only? I would think it would be much heavier than normal.

however I have not come across anyone who actually has fixed it and this is after nearly 40 years after the 101 was designed.

I have come across two people who are confident they have fixed the issue in their 101's. When I mentioned it to Anthony in Vic he bushed it off with "I just dropped the right side of the motor, not an issue"
Bill from Great Basin Rovers in US Quote - "101's have driveshaft harmonic issues and you can cure it with double cardon shafts."
The other fix I have seen is rotating the front diff housing up but this is a a biGGG dockyard job.

While no expert on driveshafts I have read what I can find on them.
Most information infers that the input/output should be parallel to cancel the change in speed of the UJ's as per below.



Wlile I have not done any measurements a spirit level tells me the motor/gearbox of the 101 slopes up This would make the make the front output shaft over-parallel to the input like this -


The rear would be obviously under-parallel like most rear wheel drive vehicles. I think the physics of being under parallel is a lot more forgiving than over-parallel. Both dropping the RHS of the motor or tilting the diff housing addresses this issue precisely.

Be interested in peoples thoughts.

Peter

Peter you are on the money.......the standard angles are not quite right and the only way to fix is roll the front diff at great cost or a Double ended double cardon shaft.
Perryscope Photos - Removing and Modifying a Landrover 101 Axel

Nice pics, rotating the diff centre is something that is not going to happen with mine quickly.
I have done 30k's with the DC shaft (DC coupling on the transfer case end, did not fit the other way) and nothing to report yet. Removing the groaning rear diff and sorting this weekend, then I might be able hear/feel any vibs from the front end.
Dropping the RHS of the motor has to be seriously considered if the DC shaft proves unsuccessful. Need to ask Anthony how much and how it was achieved.

Peter