Thread: Front drive shaft alignment.

Hi Peter,
as best I can determine, the front shaft is arranged such that its rear UJ (closest to the T/F case) "leads" the front UJ by 2 splines, with the sliding joint closest to the transfer case...
This is illustrated in the early edition of RAVE dealing with the RR "Classic" but I couldn't find it repeated in the later RAVE editions for the P38, though it is my understanding the front end alignment is the same for both vehicles. Apparently in the later Classics they pitched the front axle 12 degrees to improve straight line stability and in so doing compensated for the altered UJ thrust angles by changing the UJ phasing as described as well as bolting the elastomeric mass to the front and rear axles to counter the ensuing vibration.... a double cardan shaft is probably the only means of truly eliminating the vibration.

cheers

Thanks for that info Hoges, I can work with that!
Will give it a go over the weekend.
I know the vibration might be a worn uni joint, but will be good to know the shaft is set properly.
Cheers, Pete.

Hi

If you are sure the Uni Joints are all cool, you can have the tailshaft dynamically balanced if it still vibrates

Steve

HI

Also of course, any slight wear in the splines can cause vibration.

I have never had an issue with tailshaft vibration on any rover i have owned, it should not vibrate at all

Steve

Thanks Steve, I'm going to replace the other front uni joint to eliminate that from the list, while I have it apart I'll line up the drive shaft and see how it is from there.
Failing that I'll do the rear uni's as well, may have to get the raod wheels balanced incase I've lost a weight off a rim.
Failing that I'll be looking at getting the shaft looked at.
Cheers, Pete.

Complete "how to" track vibration... Prop-Shaft Phase

cheers

Ive just had my 2000 p38 front propshaft overhauled and balanced.
When I got it back to my shed for fitting it wouldnt slide in and out. So back to the gearbox shop I went knowing they had put it together incorrectly. The for aft part - hookes joint I think- key in only one way. If you look inside the female side you will see a machined out spline. This ensures it can only go together one way.
So I insisted that I inspect the splines for damage when they got it apart - It was stuck pretty hard. I inspectd the splines. carefully and luckily no damage, eventhough they had forced it together.
Interestingly the senior man turned up to take control and said that because it had been miss splined it would need a rebalance now that it was put together correctly.

However they spray painted over my witness marks which I made on removing from the car - eventhough I said do not spray over these marks.

So make sure it is splined correctly on reassembly, cause even the specialists get it wrong.
Also make sure the hookes joint - sliding bit- goes against the transfer case on refitment - you probably know that already.

Interesting peter51, I did notice the inside of the spline did have a gap instead of one of the splines.
Are you saying it only goes together one way? If so, that would make a lot of sense, as it would be all too easy to assemble the wrong way, as I could not see any marks to line anything up with.
It was hard trying to refit the shaft from underneath, I noticed it would not go on until I rotated the shaft around, then it would slide on ok. So maybe the shaft is on the correct way and the other uni joint is the culprit.
I may have to take the shaft back off, will be easier to see when not laying under the car.