I have a problem with my recently bought S Type 2.7SE diesel (2006) if you drive with a "feather" foot the car goes through gears smoothly if it is driven hard (or heavily laden) the car shakes badly between 30 and 50. The car has been back to the garage and had a second hand gearbox (from a 25000 mile car) but the fault is still present, the car is now to have an recon box fitted, has anybody had this fault or any ideas as to the cause, I am not certain that the box is at fault

hi and welcome to the club

so if you drive it smoothly at 30-50 it has no vibration?

are you sure its not the drive shaft or rear differential?

That was my first thought but if the car is hot after a motorway run no matter how you drive it will still vibrate, unless a u/j is braking down when the grease is hot? If you drive smoothly from cold or normal driving conditions it is fine.

Just a update the car went back into the dealers and had a (new) secondhand gearbox fitted but that gave exactly the same symptoms, it went back again and had a exchange gearbox fitted with a exchange torque converter, turned out it was the torque converter at fault, they didn't change it first time around.

Mine is doing the smae thing, its a good thing I found your post.

 

 

 

 

Just a update the car went back into the dealers and had a (new) secondhand gearbox fitted but that gave exactly the same symptoms, it went back again and had a exchange gearbox fitted with a exchange torque converter car tires, turned out it was the torque converter at fault, they didn't change it first time around.

Just to add to this.

Unless the car has high mileage, and not had an oil change, the torque converter is damaged by glycol intrusion.

The common failure is the oil cooler splitting and contaminating the gearbox oil with antifreeze. A glycol test MUST be carried out prior to torque convertor replacement otherwise the same will happen again.