GQ Tailshaft Vibrations???

Is the vib right thru the car?

Your caster angle could be out, but a small lift like that in a LWB shouldnt make any difference.

Were the Unis installed correctly? Was the vibs happening before the unis went in?

Check your bushes in the front end?

Gearbox and engine mounts?

Aussie

I had a GQ wagon 1993 5sp 4.2 injected petrol.

I has the same problem. I hope your problem is not what mine turned out to be but here's my story..

Vibration was in 4th and 5th gear above 80km/h

I'll give you the short story but I endured a long and frustrating info search with Nissan Aust and my local dealerships.

I eventually found an experienced Nissan workshop foreman who was sympathetic to my cause and gave me a bit of info.

He told me that 'some' of the Patrols were experiencing this problem and it was brought on by the gear box. A possible remedy was to rotate the drive shaft to a different position, drive it and see how you go. (all up that means 16 different possible positions for the shaft.) ie 4 bolts at the front x 4 bolts at the rear.

Anyway, the dealer did it for me to try and resolve the problem. When I got it back, the good news was that 4th gear was now smooth but 5th, they couldn't work out.

I tried to fix it my self by rotating the shaft, had it professionaly balanced,,,you name it. NO JOY. I even did the Uni joints as you stated.

After getting friendly with the foreman, after many conversations with him, he told me that Nissan knew about it and had had engineers from Japan over in Oz trying all soughts of things to try and fix the prob. The short story from here is they couldn't find a way and the reason for the vibration is the spline shaft on 5th. It somehow goes out of centre and just gets worse.

Evidently they have replacement shafts which were manufactured and 'balanced' to replace the buggered ones. I was quoted $2800 back in 1999 to do the fix. The scary thing was that they would not guarantee the work. I couldn't believe it.

It was obviously well out of warranty by the years, but only had done 122000k's.

Rather than taking the risk, I traded the car to a dealer who test drove it under 80km/h and thought it was great.

So I know that's not what you wanted to hear but it may give you somewhere to start.

GOOD LUCK.

Hi Aussie,
Check that the unis at both ends are aligned with each other, ie when two of the four "spokes" (what are those things called, anyway???) are horizontal on the uni at the diff end, two are also horizontal at the transfer end.
Tim Z

Hmmmm more Nissan problems!

I had a vibration problem in my GQ at around 85kph tried balance and alignment but didn't help.
Tyres where about 40% so I bit the bullet put new tyres on and no more problems for the last 50,000k's.
Just my two bobs worth.Bush Bappo's 4WD Club
Get out there & have a look

Try someone elses tires and rims.

Also,
Tailshaft, if the cause, is quite high frequency compared to tyres, wheels. I had tailshaft vibes many years ago in a Kingswood V8 which took a bit to cure...
I like the idea of taking it for a drive without the rear shaft in place....
I've also had tyres on another vehicle (not 4WD) which were out of round and out of balance- you could take them to a tyre shop till you were blue in the face and they'd be different every time. New tyres fixed the problem- they paid!
Cheers- and good luck.

Thanks all for the ideas,
Just to add some more, the uni's were installed correctly, the rims are new, and it still vibrates on different rims and tyres and even tried it with the a heavy load in the rear to drop the height a little. I'm trying another tailshaft to see if its worth getting it balanced or not. Hope its not the spline as mentioned above.

I HAVE THE SAME PROBLEM WITH MY 94 PATROL . MY VIBATION COMES IN AROUND 105K AS OF YET HAVE NOT BEEN ABLE TO FIND CAUSE OF PROBLEM HAVE CHANGED UNIS AND CHECKED ALL MOUNTS ITS A VERY DEEP VIBRATION COMING THOUGH FLOOR PAN UNDER MY FEETAND PULSES ????