Outer Limits 4x4 Board

I have a weird noise coming from the clutch / gearbox area when its cold. In the mornings when I start the patrol there is a noise sounding like a hammer hitting the bell housing, but when the clutch is pressed its quite. But after the patrol has driven for a few k's no noise also if the whether is warm no noise, only happens when started on cold nights or mornings when colder its louder.

Getting to the stage of taking it into the dealer leaving it there over night and being there when they start it so I can point out the noise. Other than that you guys / gals have any idea's.

Rossco

god only knows, i havnt done that much investigating, but i know exactly the noise you are talking about, although I would have described it as a definative knocking sound, prob why i havnt bothered looking for it yet. Im thinking it almost could be gearbox oil related, being when its cold the oil is more viscous and the input gear is pushing the oil around disturbing something else, which is why it goes away when you push in the clutch. knocking isnt fast enough to be direct contact with any driven parts, but almost seems too regular to be oil related.

im just grasping at straws....

GeneralFubashi wrote:god only knows, i havnt done that much investigating, but i know exactly the noise you are talking about, although I would have described it as a definative knocking sound, prob why i havnt bothered looking for it yet. Im thinking it almost could be gearbox oil related, being when its cold the oil is more viscous and the input gear is pushing the oil around disturbing something else, which is why it goes away when you push in the clutch. knocking isnt fast enough to be direct contact with any driven parts, but almost seems too regular to be oil related.

im just grasping at straws....

Hi General I never gave that a thought with the oil, Nissan did do a full oil change engine, gbox, diffs etc but I can't remember if the noise was present then. Next week I'll take the patrol into nissan leave it over night and be there when they start it so I can point out the noise, at least I still have warranty. I'll let you know General what they come up with.

That would be great thanks, my truck is an 02 model, so there isnt a lot nissan is going to do for me. However i do remember changing all the oils and only noticed the noise sometime after. Still just speculation though.

So please do keep me posted
Cheers
Sam

Mine's a 2001 TD42.
I've got a similar noise, although more like a rattle when off the clutch.
Might be time for an oil change.
What is the best oil to use for the manual gearbox in the TD42?

Thanks

At work today and had a chat with a friend of mine he was telling me that some Landrover gearboxs have the same problem ( his had the same noise as such ). He checked it out with a UK rover mechanic and he was told that there isn't enough preload on the lay shaft bearings in the gearbox. So I will be for sure seeing nissan next week.

Tractor with the gearbox oil my manual calls for a API GL4 rated 75w/85 viscosity oil, any of the brand name oil companys will make it.

Thanks for that Fox Shooter, its certainly sounds like its the case, I can definately see how it can be a problem on landrovers, but i wouldnt have expected it on a nissan. Im not overly worried.

Cheers

Took the Patrol into the nissan dealer and left it over night but due to it being left inside the workshop and being a mild morning no noise . But at least I have a tape recording of it and they confirmed there is a noise but need a cold morning for them to track down .