DAIMLER Super V8
I have an occasional problem with engaging drive in my Daimler Super V8 (the doors also do not lock), and the gear lever feels somewhat stiffer than that in my Sovereign X300 which moves about very freely. I have stripped out around the gear lever assembly to oil the linkage and have also tried to get some oil on the cable at the gear lever end with little improvement. Most of the time the gears work perfectly, so I am not sure if I have a cable problem or it just needs some adjustment?
The second problem I have is a vibration that starts at exactly 69/70mph; it feels like it's coming from the propshaft/rear of the car. Everything is extremely smooth up to that point, with no noise of any description. Although new tyres have been fitted, they have all been off and rechecked for balance.
Lastly, in the March issue you commented on changing XK8 gearbox fluid. I found this very interesting, as I would also like to fully change this oil. Regarding the quantity required, surely if it's fully drained is there not a set amount to replenish?
The gear selection problem is most likely to be a poorly adjusted or faulty selector assembly, which also contains switches for the locking system, reverse lights etc, but it may also be due to a stiff selector cable not allowing the lever to centre correctly in a particular gear. If the engine has a missing or poorly fitted earth lead, the selector cable can effectively become an alternative earth circuit, with the current flow causing heat and subsequently distortion/sticking.
There have been numerous complaints of vibration in the X308, to the point where Jaguar supplied its dealers with special sensors for diagnosis. At one stage it recommended measuring the radial force variation of each wheel on a special machine and then refitting the wheels in a particular order and with the point of greatest force pointing down (a setting that would soon be lost due to variation in tread depth). Do a thorough check of all bushes and mountings - we have heard of issues regarding the rear suspension bracing and ride height, but cannot find any Jaguar literature to confirm this.
Regarding the transmission fluid, it is impossible to drain the torque converter and cooling pipes completely, the amount draining back into the sump dependent on time and temperature. It is therefore impossible to set an exact refill volume, and these Mercedes-Benz/ZF transmissions are extremely finicky when it comes to fluid level.