driveline vibrations

[giacomo.m]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

[Bush65]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

If you have fitted a rear drive shaft that has a cv at the transfer case end, then you need to adjust the suspension links so the diff pinion is aligned with the drive shaft. In other words, so that there is no angle change in the rear universal joint.

You could make an adaptor for the ball joint mount to the upper A frame to move the ball joint down and further to the rear. Or make shorter lower links.

[Micka]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

Did the stock shafts cause vibrations with a 2" lift?

Micka

[giacomo.m]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

If you have fitted a rear drive shaft that has a cv at the transfer case end, then you need to adjust the suspension links so the diff pinion is aligned with the drive shaft. In other words, so that there is no angle change in the rear universal joint.

You could make an adaptor for the ball joint mount to the upper A frame to move the ball joint down and further to the rear. Or make shorter lower links.

Hi bush 65

you task to the product : rear A Arm Extension of Rovertym ?
and in the case it is sufficient this ,or I have need also of shorter lower links ?

Thank you.

James

[Bush65]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

If you have fitted a rear drive shaft that has a cv at the transfer case end, then you need to adjust the suspension links so the diff pinion is aligned with the drive shaft. In other words, so that there is no angle change in the rear universal joint.

You could make an adaptor for the ball joint mount to the upper A frame to move the ball joint down and further to the rear. Or make shorter lower links.

Hi bush 65

you task to the product : rear A Arm Extension of Rovertym ?
and in the case it is sufficient this ,or I have need also of shorter lower links ?

Thank you.

James

I don't know if the Rovertym A arm extension will correct your pinion angle or not - it depends upon where the bolt holes in the extension are located.

I haven't looked at the rovertym info on the A arm extension for a long time, so I don't know if it is intended to correct the pinion angle to suit driveshafts with a double cardan (cv) joint. It may do, or you may be able to drill new holes to suit.

You could always make your own A arm extension, similar to the rovertym one.

I would rather correct the pinion angle with an A arm extension.

One possible disadvantage is that your drive shaft may be too short with the A arm extension (you will have to check). That is the only reason that I would shorten the lower trailing arms/links.

[giacomo.m]

Hi,
therefore if I have very understood,if I only fit A arm extension I can resolve the problem of pinion angle to suit driveshaft with double cardan.and with the assembly of the lower trailing arms/links (without A arm extension ) I can resolving the problem ?
Thank you.

[Bush65]

Hi,
therefore if I have very understood,if I only fit A arm extension I can resolve the problem of pinion angle to suit driveshaft with double cardan.and with the assembly of the lower trailing arms/links (without A arm extension ) I can resolving the problem ?
Thank you.

I have just had a look at the rovertym web site. This is what they say about the A arm extension.

This extension is used when needing additional tire clearance at the rear door, or needing to rotate axle up to help in solving rear pinion angle problems. Bolts to A Arm and relocates existing rear swivel link to the rear up to 1" maximum.

Also for 3" or more lifted trucks this link will restore some of the lost Rear A Arm swivel joint geometry which diminishes as we lift the suspension.

Set back is to customer specs. This may require lenghtening rear links depending upon purpose used for. Moving rearward 1/2" results in a change in pinion angle of approx. 3 degrees.

Made to Custom Specs $150.00

In the pic there are 2 sets of holes that enable 2 different pinion angles.

They say moving rearward 1/2" (13 mm) changes the pinion angle by approx 3 degrees. They will make whatever extension you specify.

Before doing this you need to determine how much to change the pinion angle. I can't help you there because defender 90's are rare in Australia, so I have no idea what the angle of your rear double cardan driveshaft might be.

When determining what the pinion should be, remember that the pinion flange will rise as the pinion is rotated up - thus changing the angle of the driveshaft.

I would disconnect the drive shaft from the pinion flange and support it so that it is pointing toward the centre of the differential (the axis of the axles). It should be higher than the pinion flange. Then measure the angle of the driveshaft to the horizontal.

This is the angle that that the pinion needs to be rotated to. So measure the angle of the pinion and calculate the change in angle required.

Now if you use that information from rovertym - that 13mm (or 1/2") extension rotates the pinion by 3 degrees - you can determine how much extension is needed.

Also you might get extra holes made incase you need to make a further adjustment either way.

Here are some pics from rovertym web site http://www.rovertym.com/

[giacomo.m]

Hi,
I have just had a look at my set up.:
- angle of connected driveshaft to the horizontal : 16°
- angle of flat low part of the nose differential : 8°
therefore I believe that I must up compensate( rotated up the nose differential ) one difference of approximately : 8°
and your advice a to fit the multiple double cardan drive shaft (4 u joints total) of Tom Wood's for my problem ?
Thank you

[Bush65]

Hi,
I have just had a look at my set up.:
- angle of connected driveshaft to the horizontal : 16°
- angle of flat low part of the nose differential : 8°
therefore I believe that I must up compensate( rotated up the nose differential ) one difference of approximately : 8°
and your advice a to fit the multiple double cardan drive shaft (4 u joints total) of Tom Wood's for my problem ?
Thank you

With a double cardan joint at the transfer case end of the driveshaft, the angle of the driveshaft should be approximately the same as the angle of the differential pinion. 2 to 3 degrees may be ok but more will cause vibrations.

The angle that you need to rotate the differential will be less than 8 degrees, because the pinion flange will rise as the differential is rotated and this will reduce the angle of the driveshaft - the driveshaft angle will not stay at 16 degrees.

I would not put a double cardan joint at both ends of the driveshaft. It should cost less to use an A-arm extension and the results will be better - gets the pinion flange and lower end of the driveshaft higher (more ground clearance) and reduces the angle of the driveshaft (better for the joints).

[giacomo.m]

Hi,
I have just had a look at my set up.:
- angle of connected driveshaft to the horizontal : 16°
- angle of flat low part of the nose differential : 8°
therefore I believe that I must up compensate( rotated up the nose differential ) one difference of approximately : 8°
and your advice a to fit the multiple double cardan drive shaft (4 u joints total) of Tom Wood's for my problem ?
Thank you

With a double cardan joint at the transfer case end of the driveshaft, the angle of the driveshaft should be approximately the same as the angle of the differential pinion. 2 to 3 degrees may be ok but more will cause vibrations.

The angle that you need to rotate the differential will be less than 8 degrees, because the pinion flange will rise as the differential is rotated and this will reduce the angle of the driveshaft - the driveshaft angle will not stay at 16 degrees.

I would not put a double cardan joint at both ends of the driveshaft. It should cost less to use an A-arm extension and the results will be better - gets the pinion flange and lower end of the driveshaft higher (more ground clearance) and reduces the angle of the driveshaft (better for the joints).

Therefore the best set-up : rear A-arm extension with genuine lower link ?
or with shorter lower link ?
problems of alignement of low part of coils spring ?
Thank you.

[Bush65]

Defender 90 are rare in Australia and I have never worked on them.

I would use the A-arm extension and standard length lower trailing arms/links.

With lifted suspension an A-arm extension can allow more articulation before the ball joint binds.

With an A-arm extension, your wheel base will increase a little (about 1/4 of the A-arm extension). I doubt if this will cause the tyres to rub anywhere, or cause any problems with the driveshaft, but I am not familiar with D90's.

Shorter trailing arms will reduce the wheelbase (about 3/4 of the difference in trailing arm length. I don't think this is good with 90" wheelbase. Also anti-squat and roll steer will be worse - again not good.

If you are dislocating your rear springs on maximum down travel, the change in angle of the lower spring seat could cause the top of the springs to not seat properly when the axle returns to normal.

There are 2 solutions that come to mind.

1. correct the angle of the lower spring seat by packing under the rear of the spring seat.

2. retain the top of the springs (as well as the bottom) so that they can't dislocate.

Here, people that have tried all 3 methods:
1. springs retained at the bottom only
2. springs retained at both the bottom and top
3. dislocating springs
have found that the 2nd method, retaining the springs at both the bottom and top is best and this is what I recommend.

[tony cordell]

http://forums.lr4x4.com/index.php?showt ... &p=&#entry

I wasted lots of ££ on sorting this problem.
same set up
OME +2" on a 90.

I thinlk the problem is the front not the rear, unless you have worn UJ's n the prop

[giacomo.m]

http://forums.lr4x4.com/index.php?showt ... &p=&#entry

I wasted lots of ££ on sorting this problem.
same set up
OME +2" on a 90.

I thinlk the problem is the front not the rear, unless you have worn UJ's n the prop

Hi Tony,
Defender 90 200 Tdi 1992 with new front Equipe4x4 drive shaft (8000 Km).

Giacomo

[Bush65]

Hi all

I have Defender 90 200 tdi 1992 with +2" OME,news front and rear drive shaft CV Equipe4x4 ,but still driveline vibrations in acceleration 50/60 Km/h and in overrun.but when I remove rear drive shaft,all ok no vibrations. why?
Thank you.

James

[tony cordell]

Doh!
the front can cause the over run vibes, the rear prop hs a much easier time than the front.
a wide angled front prop made no difference to mine
the Disco2 one sorted it after replacing:
transfer box
front diff
rear prop
front prop x2
bushes
wheels balanced
removed crawler box incase...

[darthdicky]

Do you actually need a CV shaft on the rear? Have you tried a standard one to see if that gets rid of the vibrations?

Richard

[Michele]

removed crawler box incase...

In case...!