S type vibration

[ATKY]

Have a 2007 2.7D S type with a vibration problem.The car drives perfect apart from a vibration which starts at about 50 mph.The vibration comes through the car,not the steering wheel.The wheels/tyres have been replaced,the prop as been off and had a new rear section due to spline wear,but the problem is still there.Has anyone had this problem with their S type?Also the car is an automatic,but the log book states its a manual and any searches done about the car say its a manual,is this how jag describe the box due to the manual selection option?Thanks in advance for any info.Regards,Steve.

Edited by ATKY on Thursday 3rd November 21:57

[Cecil]

Hi, do you still have the 50mph vibration ? I am trying to work through a similar problem on an X308.

Thanks

C

[Jaguar steve]

Cecil said:

Hi, do you still have the 50mph vibration ? I am trying to work through a similar problem on an X308.

Thanks

C

All the 308's I've driven have a very faint vibration period under steady throttle at 50MPH - It's very sublte and nothing serious. 50MPH is slightly slow for 16/17" wheels to show balancing problems - this usually worsens significantly between 55/65MPH at those diameters, but you may have an out of round tyre or wheel out of true. Try swapping wheels around first and whilst the car is jacked up turn each wheel to feel for tight spots and any bearing slack and look and feel for any deformaton of the tyre. Try gentle braking from high speed and see what happens as you decelerate through the vibration speed. Is it better or worse with the brakes applied? If it's better then suspect bushes or shocks, if it's worse then you may have a warped disc. If you feel the vibration through the steering wheel then the front discs are suspect and if you feel it through your arse and not the steering wheel then it's the rears. If it's felt through both....well you work it out.

If the vibration is worse as you accelerate through 50 then suspect either the propshaft centre bearing or the flexible couplings - you can reverse these as a diagnostic test but they will need replacing if doing so shows improvement.

Make sure all 4 halfshaft UJs are well greased too - most Spannermonkeys don't even know what a grease gun looks like nowadays and these are often overlooked.

[Cecil]

Jaguar Steve many thanks; the problem persists after change of all wheels and tires, new disks and pads all round too. I have had a full geometry check done and it is within tolerance. If I brake it is worse until it drops to about 40. I have had all of the bushes checked and replaced, and am on my second set of front shocks, in four years, it is an XJR with CATS. On some road surfaces it does not show up, but when it does, you can feel it through the base of the seat, the steering wheel, and the floor, it is also noticeable on the passenger side as a vibration through the floor. Once you hit about 60 it fades, and at 80 you hardly notice it, it creeps in a bit more at 90. When at 50 on a bad surface you can clearly see the judder in the steering wheel.

The UJ’s are ok, and I have had three wheel bearings changed in the last two years.

I will try the gentle braking from a high speed and see what happens at 60-40,

It is due to go for some more "care and attention" in the New Year, I will get them to look at the prop shaft bearings and couplings too.

Once again many thanks for your suggestions.

C

[Jaguar steve]

Cecil said:

Jaguar Steve many thanks; the problem persists after change of all wheels and tires, new disks and pads all round too. I have had a full geometry check done and it is within tolerance. If I brake it is worse until it drops to about 40. I have had all of the bushes checked and replaced, and am on my second set of front shocks, in four years, it is an XJR with CATS. On some road surfaces it does not show up, but when it does, you can feel it through the base of the seat, the steering wheel, and the floor, it is also noticeable on the passenger side as a vibration through the floor. Once you hit about 60 it fades, and at 80 you hardly notice it, it creeps in a bit more at 90. When at 50 on a bad surface you can clearly see the judder in the steering wheel.

The UJ’s are ok, and I have had three wheel bearings changed in the last two years.

I will try the gentle braking from a high speed and see what happens at 60-40,

It is due to go for some more "care and attention" in the New Year, I will get them to look at the prop shaft bearings and couplings too.

Once again many thanks for your suggestions.

C

Bit of a loss to suggest anything else now - you've replaced practically everything that might cause a vibration problem like you describe - and it sounds pretty bad if the steering wheel is vibrating. If it's road surface dependent then making sure tyre pressures are correct, or playing around with different pressures might give you another clue to investigate. One thing comes to mind 'tho - if it's worse under braking than that usually points to discs, especially as you have vibration through the steering wheel and seat. Were the replacements OE or patern ones? If the latter it's not unconceivable the new ones have warped - especially if you spank it a bit.

Best get someone who has experience with XJs to have a look round.

[Cecil]

I had a chance to take it out for a decent run last night, the vibration comes as you accelerate past 50, if you boot it from 40 to 70 you don’t feel much, if you accelerate slowly, say over 10 seconds, from 40 to 70 it is very notable, where it is most apparent, is when backing off the throttle at 70 and letting the speed come down, without braking, as soon as it dips under 60 the vibration starts, and gets worse, until the speed drops just below 50 then it disappears. If I brake slowly from 70 you can feel the vibration but it is not as bad, if I brake hard when the vibration is at its worst, it seems to help, but that may be because of the change in speed.
The car has the Berembo option, but after suffering a lot of vibration due to builds up on the disks, I have had them replaced with a brand I can’t remember at the moment, but matched with Ferodo DS-2500 pads, and the difference is fantastic, much better in terms of stopping power, and no build up so far, touch wood.

Driving the mandatory 50 mph section on the M25 between the A12 and the Dartford crossing was horrific, with the car vibrating, tram lining and wandering over the poor surface, I got on to the A2 and up to 70 and everything was back to normal, effortless wafting

I also tried the car in gearbox selector 3 and 4 last night instead of just D, exactly the same vibration in all gears.

Many thanks

C

[Jaguar steve]

Cecil said:

I had a chance to take it out for a decent run last night, the vibration comes as you accelerate past 50, if you boot it from 40 to 70 you don’t feel much, if you accelerate slowly, say over 10 seconds, from 40 to 70 it is very notable, where it is most apparent, is when backing off the throttle at 70 and letting the speed come down, without braking, as soon as it dips under 60 the vibration starts, and gets worse, until the speed drops just below 50 then it disappears. If I brake slowly from 70 you can feel the vibration but it is not as bad, if I brake hard when the vibration is at its worst, it seems to help, but that may be because of the change in speed.
The car has the Berembo option, but after suffering a lot of vibration due to builds up on the disks, I have had them replaced with a brand I can’t remember at the moment, but matched with Ferodo DS-2500 pads, and the difference is fantastic, much better in terms of stopping power, and no build up so far, touch wood.

Driving the mandatory 50 mph section on the M25 between the A12 and the Dartford crossing was horrific, with the car vibrating, tram lining and wandering over the poor surface, I got on to the A2 and up to 70 and everything was back to normal, effortless wafting

I also tried the car in gearbox selector 3 and 4 last night instead of just D, exactly the same vibration in all gears.

Many thanks

C

Right - so it's road, not engine speed dependent, worse under light loads and is damped by both hard braking and hard acceleration yes?

Best guess? Propshaft out of balance or not running true.

I think you should get that up on a ramp and have the shaft, UJs, flexible couplings and bearings checked soonest.

[ginettajoe]

..... What tyres are fitted to the car??

[ginettajoe]

..... What tyres are fitted to the car??

[Cecil]

Many thanks Steve, that is correct, I will do and report back, it makes sense and is about the only area I have not touched yet.

Current tires are Toyo T1R and previously Goodyear Eagle F1 DS3

[ATKY]

Sorry for delay in replying.Problem is now fixed,it turned out to be prop after all.The prop had a new rear section plus balance but was still no good,so it was replaced with a used low milage one from a salvage yard.All ok now.Regards,Steve.