[davevet]

Hey there guys,

I just bought my first sierra woohoo

It is a soft top with fibreglass roof and canopy. Engine runs really nice, but I'm struggling to find a vibration and noise coming from the drive train.
Firstly:
I have replaced the uni on the jack-shaft (had heaps of lateral play), made a large difference to noise levels.
I have also replaced one uni on rear tailshaft (seized) which cured my vibration at 90kmh.
I have swapped the gearbox for a spare to try and narrow it down... problem still exists.
I have put transfer in neutral, placed in second gear, and could hear a deep rattle, when i placed my ear on gearshift and transfer shift it appeared the noise came from the transfer...

Under heavy load, pretty much full throttle in any gear up to 3rd causes the wobble.....its quite a harsh vibration, felt through the entire vehicle. Most prominent at low rpm and max throttle.

There is a small amount of play in the second of the tail shaft uni joints, it has no rotational free play but has a tiny bit of lateral play... could that cause this problem?

Also, is it normal if you plant it in 4th gear at low rpm, 2000ish to hear rattly noises coming from the drive train?


thanks in advance,

Dave

[Perram]

Checked your rubber mounts?
Eng
Gearbox
Transfer

[atari4x4]

could have kept this one going... viewtopic.php?f=5&t=46821

[AckerDackerly]

One of the most common causes of noise like this is a damaged transfer case mount.

Also, did you reassemble your propshafts using the alignment marks? An incorrectly assembled propshaft can cause vibration problems:


http://acksfaq.com/driveshaftvideo.htm

[davevet]

sure did check the shafts - one wasn't aligned to begin with ... couldn't find any marks so i just made sure the yolks sat the same on both ends.

Ok, cool I'll give everything a good shake tomorrow - see if that yields and problems!

atari4x4 - Nobody replied to that thread lol was up for a few days....

[atari4x4]

ummm this is not facebook, you can bump an old thread to keep it going and it helps keep the info in one spot rather than spread all over the shop.