Nissan Patrol 4x4 (Africa)

Here is the situation.
After every mud sesion with my patrol there is a heavy vibration comming from the wheels or drivetrain. We did Leeuwenboschfontein over the weekend and it was raining. Lots of mud, slipping sliding and the rest that goes with it.
We packed up on Sunday and left for CT. On the slipery gravel road I was driving in 4x4 H at 80km/h and felt the vibration.
1. First thought was that there were mud or stones sitting on the inside of the rim. This was not the case as I stoped at the tar road to clean the rims with water and removed the visable sand and stones.
2. On the tar road in 4x2 H the vibration was still there. I stop to refeul and asked the petrol attendent to was the wheels properly and hit the road after that. Still the same vibration. 15min stop.
3. Then stoped at my parents place to drink coffee. When we left them the vibration was gone. 45min stop.
Now my question is.
(No wheels were washed at my parents place.) Can it be that one of my auto free wheel hubs does not unlock and thus cause the front propshaft to keep spinning and when I did a 45min stop it disingaged. (does it work on vacuum)
This was not a problem in Saddle Hill doing 80-90km/h.
Any advice is welcome. I'll be back next week to check the forum.

Geesh...thats quite a difficult one...sounds like a very annoying problem!

My best guess would be theat one of the front auto hubs is not disengaging properly.

It's a bit of a lass, but conventional wisdom seems to be that if you want to protect the hubs during "heavy" 4x4ing, then rather lock them manually before you start playing.

Its quite easy to take the hub mechanism appart, so it might be worth pulling them both off and checking that they`re clean and properly lubricated. When you re-assemble them just make sure you don`t over-grease them as this can also cause hassles.

Also,when using the hubs in auto mode make sure you remember to reverse a few meters after changing back to 2H, as this helps the hubs to un-lock.

The only other thing that I`ve every experienced, which might be worth a check, is the dust cover on the end of the prop shaft (I think the front and rear prop both have them). This is held on with a tiny spot weld, and if it comes loose it can cause a horrible noise, and slight vibration.

Hope this helps a bit!

Good Luck,

Ross

Howzit Vaaitjie and Ross. I was out 4x4ing yesterday and on my way back had a similar vibration issue. After reading both your posts, I went out to my vehicle and saw my one hub was not fully on auto! I turned it slightly and "click" it went into auto. I checked underneath my vehicle and could see traces of grease around the front uni's as it got sprayed around! I greased all my uni-joints on friday and did not clean off the excess grease that came out the sides. Thanks guys you saved me a lot of Cheers.

The vibration comes from the front universal joint. I drove on the dirt road and shifted the Patrol from 4H to 2H and continued my journey on tar. The Patrol did not disengage the front diff from the wheels and the wheels-diff-driveshaft was turning and this was were the vibration was coming from. You have to stop, shift to 2H, reverse at least 1m and then continue with your trip. A simple test is to manually put the PATROL hubs in the lock posision and leave the transfer case in 2H.Drive to 80-100km an hour and see if you feel in vibrations.(not the radio) If you have a standard suspension it should be quiet and with the raised suspension, the back nuckle on the front driveshaft, becomes noisy. Thy this out and see if my conclusions holds any water.