Resonnating Rattle from Prop/transfer or ???

[gerry2004uk]

Hi guys,

I have a Terrano II 1998 se Touring 2.7d 5 door.I have a rattle which I assumed was exhaust related at first. It happen's when I have the car in slighty too high a gear or when slowing down at road ends.

I had assumed it was a loose clamp or something like that but I have had the exhaust checked out at a tyre/exhaust type place and it is all fine.The mechanic suggested that it could be something to do with the prop shaft or transfer box and suggested I get that checked out.

I have read some old posts regarding worn uj's but I dont think they are at fault as the vibrating sound doesnt happen within a specific speed range (55-63).I removed the large prop shaft last night (in a bit of a rush admittidly as it was getting dark) to have a look and the uj's and they felt quite smooth,which is a shame as they look like the cheapest components to change !!

There seems to be a bit of rotational play in the prop shaft,about a quarter of an inch in the shaft.Ie i can twist it left and right a little.Is it possible that something is worn where it engages in the gearbox at the front end ? and if so can it be replaced or fixed somehow ? Would that cause a loud vibrating noise.

The transfer box was mentioned as a potential problem but I do not have a good understanding how it works.I never drive the jeep in 4x4,always rear wheel as i dont off road or anything like that.Could this be a cause of loud vibrations and what would be the best way to rectify.Is the transfer box the smaller one on the nearside with the little shaft connecting to the gearbox ?!!

Sorry about the long post guys but i tried to give as much info as poss !

Thanks in advance

 

[briggie]

i had this problem , and it turned out to be a guard that fits around the knuckle joint on the propshaft , it was loose , hope this helps :thumb2

 

[gerry2004uk]

Thanks Briggie ,It does sound like a flange (ooh er missus !) vibrating or something like that but I cant see a guard on my knuckle joints.They appear to be open to the elements,prehaps removed or maybe not fitted on my model ?? but i will check again in case i am missing the obvious

I now realise that the transfer box is that whole section aft of the gearbox and it has both the prop shafts coming out of it.Does anyone know where i could get one or how much it would be should i end up needing one ? recon or 2nd hand probably.

I keep coming back to this play in the large prop shaft that turns the rear wheels.I wish I could compare it to a terrano that is working,does anyone know if the one on their car rotates a little or should it not move when the wheels are on the ground.

The small prop shaft that drives the front is solid,no shimmy at all.

 

[makeitfit]

The front prop is totally irrelevant in this case. A bit of slop in the prop is fine, I've got loads more than yours :lol
The UJ though could still be the issue. Is there any play or float in it? It doesn't take much :augie

 

[gerry2004uk]

cheers for that,at least I can eliminate the front prop now and it is also good to hear that rear one has some movement as well.
.
I had the rear prop dropped out again this afternoon and whilst in one direction of movement on the uj was a little bit stiff ( at both ends) i wouldnt describe it as sloppy.I have gave them a regrease anyhow.

The noise occurs at that time when the car is at low revs and slow on the pick up,ie ,the car is trying transmit the torque from gearbox to wheels when a lower gear would be prob more suitable.

I am also wondering about that cup shaped section that the prop slips into on the transfer box,it looks like the type of thing that could generate that noise !

I might hang on the bottom of the car and get the missus to drive round and have a listen :lol

 

[rustic]

Let's not forget the rear diff.:nenau

It's a limited slip diff and if the oil is not replaced with LSD oil, you can get vibrations, more if the 2 rear tyres have different tread depth, pressure or different types.

There is backlash in all gears so the prop will have some rotational play, and if the rear diff limited slip clutches are trying to slip, they can cause the prop shaft to shudder.
If the oil is overdue, it comes out thick and grey coloured, due to the contamination from the clutches, but this is normal.


So put your closest treaded tyres on the rear and try that.
Then think about buying 3 litres of Comma LSD Oil at £4.99 a litre..


Plenty of posts on the LSD oil etc.


I think it just needs some tlc.:thumb2

 

[gerry2004uk]

Rustic,

you could be on to something there.I think I will start with that and work my way up.I have had the jeep 18 months and not done it yet .Tho i have only done 12,000 mile in that time i dont know when it was done previously.I am going to be a busy boy on tuesday when i have a day off work

I listed the car for sale last week and had a buyer but this rattle was an issue and I will get it fixed before i sell it on.So i will report back whatever helpfull information I can when i get to the bottom of it

 

[gerry2004uk]

Hi guys,problem solved !!

I checked the oil levels of the drive train this morning,all good and clean when I stuck my finger in and plugs easy to remove so I was happy with all that.

I couldnt help going back to what I thought the original problem sounded like to me, a exhaust related flange/clamp or something and having read Briggie's post again about the guards on the uj's I decided to look around the general area and inspect anything which was bolted on.

Two screws on the exhaust heat shield which sits above the exhaust have worn through causing it to vibrate through the chassis and produce the annoying shrill at low rev's.I padded the shield out and took it for a spin,no noise :clap.
I will have it rebolted on today.

Thanks Briggie for giving me the notion to look further afield and thanks to the rest of you guys for the constructive advice given.I may have lost my buyer as they found another car last night (A voyager ) but now I can relist knowing that the car is fully working.Panic over :thumb2