Which Propshaft

[peterjfox69]

Currently investigating a vibration which starts around 70mph.
Slight vibration through steering wheel but seems to come from the car in general at higher speeds.
Car just back from total restoration etc so will get wheels checked for correct balance etc.
Was curious to know if cheaper Rimmer Bros propshaft does the job or is it worth investing in the more expensive EJ Ward version if it turns out to be propshaft.
Already have new diff from Wards and CV driveshafts fitted.

[KOY 23]

Had similar, cured by fitting Minilites..

[jbuckl]

1st thing to check is wheel & tyre runout.

Jack up, spin wheel …. Observe runout….

Stags with oem alloys can runout. (No hub spigoting… roll eyes)

Can be fixed using temporary conical seating nuts x2 then swap for correct nuts.

check bearing play.

original props can deteriorate…. They had a rubber inter molding which may be perished.

Replacement props should be ok from either source…. But are not very NVH compliant…. I found they radiate a ‘dink’ when selecting drive on an automatic…. Probably due to their (solid but light and thinwall) construction…. Not a biggie though.

It would be great if there was a service to properly rebuild a stag prop inter molding…. That’s unlikely though….. GKN sad story etc. (google it)

years ago they had a drop-in service for props in Erdington …. 1hour turn around for £50! It was great…. But I had one done and the balance weight flew off just after it was fitted…. No real issue to return it back then though.

just my 2p :-

Stag oem alloys provide part of the cars styling appeal.

minilights, whilst period do look a bit rally car - esk.

oops where’s my coat?

[Seaking]

I had a vibration that was apparent at 60mph I could not drive through the vibration. The cure was to replace my tourqe converter.

[Tdafforn]

Just been through this with my stag. Caveat is that is an RV8 powered stag..
one thing i noted was that a vibration between 60-70mph is a very common stag ailment if the forum archives are to be believed
My issue ended up being a combination of things. First when i got the car the tyres were circa 1997, lovely flat spots and so, of course swapped them for modern rubber. Massive improvement but not perfect. I had original wheels which the tyre fitters really struggled to balance partly i suspect because they didn’t have the correct fitting to mount them. Vibration was particularly bad coming off power. They also had visible runout. So swapped them for a good second hand set of minilites and much smoother coming off power but still had a Seat of the pants vibration. Checked the driveshafts and found both outer ujs stiff. So swapped for CV shafts. Minor improvement but i really wanted them for the improved hubs for safety.. next swapped the elderly looking propshaft for an LD double UJ shaft… marginal improvement but not good enough. I next checked the angles of the gearbox and dif flanges and found them not to be parallel.. i chatted to a friend who has worked NVH aspects at jag-landrover. He took my measurements and checked them out with his mates who work on similar and they predicted that UJs would vibrate at 70mph. So swapped for a CV jointed prop from rimmers (which is clearly a redrilled rover SD1 prop). Good news. Now pretty much perfect. I get a very slight wobble now at 65 but is is transient potentially dependent on road surface and only occurs when on power and most of the times not at all. I wonder whether my rear suspension alignment is quite right so i might play with that at some point.
now the caveat is whether the flange angles can be non optimal on a TV8? I have asked if someone will measure them but no one has offered. But on my RV8 it was significantly beyond the limit for a uj system.
tim

[peterjfox69]

Thanks for the advice guys, will let you know how I get on

[jbuckl]

Just been through this with my stag. Caveat is that is an RV8 powered stag..
one thing i noted was that a vibration between 60-70mph is a very common stag ailment if the forum archives are to be believed
My issue ended up being a combination of things. First when i got the car the tyres were circa 1997, lovely flat spots and so, of course swapped them for modern rubber. Massive improvement but not perfect. I had original wheels which the tyre fitters really struggled to balance partly i suspect because they didn’t have the correct fitting to mount them. Vibration was particularly bad coming off power. They also had visible runout. So swapped them for a good second hand set of minilites and much smoother coming off power but still had a Seat of the pants vibration. Checked the driveshafts and found both outer ujs stiff. So swapped for CV shafts. Minor improvement but i really wanted them for the improved hubs for safety.. next swapped the elderly looking propshaft for an LD double UJ shaft… marginal improvement but not good enough. I next checked the angles of the gearbox and dif flanges and found them not to be parallel.. i chatted to a friend who has worked NVH aspects at jag-landrover. He took my measurements and checked them out with his mates who work on similar and they predicted that UJs would vibrate at 70mph. So swapped for a CV jointed prop from rimmers (which is clearly a redrilled rover SD1 prop). Good news. Now pretty much perfect. I get a very slight wobble now at 65 but is is transient potentially dependent on road surface and only occurs when on power and most of the times not at all. I wonder whether my rear suspension alignment is quite right so i might play with that at some point.
now the caveat is whether the flange angles can be non optimal on a TV8? I have asked if someone will measure them but no one has offered. But on my RV8 it was significantly beyond the limit for a uj system.
tim

all good info.

wrt to flange angles…. Afaiaa u/J s are best installed (nominal ride hight) with a non parallel angle.

to design / install parallel will give rise to undesirable wear …. A small angular misalignment is desirable.

For road cars a max inclusive angle of 15 degrees should result in vibration free long durability…. More than that & the manufacturers say expect undesirable noise.

But Fwiw, many manufacturers break the recommendations!

my stags propshaft is definitely not parallel at ride height…. Suspect most will not be and that is correct.

The reason for the recommendation is to distribute wear. (Not localise it)

A u/j installation will give constant velocity when fitted in pairs…. Fact….. despite some imagining that only cv-joints do that!

[Tdafforn]

all good info.

wrt to flange angles…. Afaiaa u/J s are best installed (nominal ride hight) with a non parallel angle.

to design / install parallel will give rise to undesirable wear …. A small angular misalignment is desirable.

For road cars a max inclusive angle of 15 degrees should result in vibration free long durability…. More than that & the manufacturers say expect undesirable noise.

But Fwiw, many manufacturers break the recommendations!

my stags propshaft is definitely not parallel at ride height…. Suspect most will not be and that is correct.

The reason for the recommendation is to distribute wear. (Not localise it)

A u/j installation will give constant velocity when fitted in pairs…. Fact….. despite some imagining that only cv-joints do that!

I guess it depends on the definition of parallel. The ideal situation for ujs is input and output flanges parallel but offset. Then you have both smooth running and low wear.. parallel and no offset gives smooth running but wear. Non-parallel with or without offset gives noisy running if beyond the specs for the uj. In my case gearbox was tail down and diff was nose down hence not parallel giving an angle beyond the permitted limit and thus vibration. You are absolutely correct. With correct geometry ujs are close to constant velocity. But that geometry is quite narrow compare to cv joints. Which is why ujs in general are nit used on driveshafts in FWD applications but CV joints are..
tim