"Bump" Steering

[bt965]

Hi ,my 2001my XKR is suffering from what i can only discribe as bump steering, that is when i go over pot hole or depressed manhole cover on the near side the car has a nasty twitch , but this dosn,t happen on the off side . I,ve checked the obvious i.e bushes,ball joints ect, can,t see any problems. anyone come accross this problem or has any ideas?
Thanks Bob
p.s didn,t mean unhappy manhole cover!

[MyQuest]

Bob.
I had the dreaded 'tram-lining' on my 99 XK8 coupe for about 3 years.
I changed all the suspension bushes/joints etc.,had the tracking laser checked/adjusted without much improvement.
Two months back I replaced the Pirelli tyres with Goodyear (Eagle F1 rear & Elegance front)- what a difference! No more tram-lining. It drives like a different car. Amazing.

Michael

[mike020150]

Hi Bob,
If you're confident that you haven't a bush/bearing problem, check the tyre wear pattern carefully. Incorrect wheel alignment could produce the symptoms you describe but the chances are that they will be accompanied by a less than perfect tyre wear pattern. Sophisticated 4 wheel laser alignment equipment is essential to set the car up as Jaguar intended. Mike.

[Nik]

Bob.
I had the dreaded 'tram-lining' on my 99 XK8 coupe for about 3 years.
I changed all the suspension bushes/joints etc.,had the tracking laser checked/adjusted without much improvement.
Two months back I replaced the Pirelli tyres with Goodyear (Eagle F1 rear & Elegance front)- what a difference! No more tram-lining. It drives like a different car. Amazing.

Michael

I got an amazing improvement/cure with Dunlop Sport Maxx's and as a plus side they have the Jaguar "J" extra load rating on the sidewall ,

Hope this helps ,

Nik

[GrandTourer]

I also changed my tyres from the Pirelli P-Zero's to Toyo Precis T1-R just prior to a Continental Alpine trip - returned yesterday having covered about 2,500miles on the trip, mostly dry roads but quite heavy rain on one day. The car felt much, much better than it did with the Pirellis on previous similar trips.

The complete set of 18" tyres, 245/45 fronts and 255/45 rears with the correct load and speed ratings cost about £600, complete with fitting, balancing, etc.
Whilst I was able to find similar deals in the past for the Pirelli, they now would have cost over £250 more than the Toyo.

I have also fitted the Toyo on the front of my X-type 2.5l 4-weel drive in August last year with great results.

[bt965]

Thanks for the replies, unfortunatly i,ve just fitted new pirelli,s all round and had the geometry checked on a Hunter machine. As for abnormal tyre wear the car was running on 20" wheels before I bought it, the vendor swapped these for double fives from a cabriolet he also owned so if it is a tyre problem I suppose i.ll just have to live with it till next change, or win the lottery of course.
Thanks again Bob