Nissan Patrol 4x4 (Africa)

Guys, when I've been driving at speed and coast to a stop at an open road intersection, just before I come to a dead stop, there is a single clonk as the box shifts down; ie a slightly harsh downshift. Is that normal? A new 4.8 GRX.

Hi Clem.

Mine also did it from day one. I think it is related to the idling speed and it's behavior changes with your driving style.
Try coasting in slowly before you come to a stop.

Check out this link: Thud

You can also try resetting the TCU by unplugging it over-night and by adjusting your timing to 10 degrees advance as yours are more than likely still a factory stock 5 degrees.

Must say it is quite an unrefined clunk

Let us know if that helps

David wrote:Hi Clem.

Mine also did it from day one. I think it is related to the idling speed and it's behavior changes with your driving style.
Try coasting in slowly before you come to a stop.

Check out this link: Thud

You can also try resetting the TCU by unplugging it over-night and by adjusting your timing to 10 degrees advance as yours are more than likely still a factory stock 5 degrees.

Must say it is quite an unrefined clunk

Let us know if that helps

Many thanks for the input David. I'm not sure about the aircon thing - will monitor but I think in my case I did not have it on, but I could be mistaken. The TCU is the transmission control unit? Maybe I can just disconnect the man in batty overnight instead? 5 degrees advance on the engine timing? If that's all it has I probably really should get it changed - obviously set to cope with really low grade fuel (?).

You can do so but it is actually very easy to disconnect the TCU.

Stick your head under the dash drivers side. It is mounted below the radio. It has a lever that flips open and then the connections can be removed.

If you disconnect the battery your radio will ask for a code and you will have to reset all the stations

David

Thank you David.