Thread: rattling diff / axle when coasting

Transfer case problem???

Failed UJ.
Regards PhilipA

I thought of those as well but the UJ's seem fine. I recently greased them so I thought it was related but I can feel no play on them at all and there was plenty of grease in them. No water whatsoever.

The transfercase, maybe, but the sound definitely is coming from the front so I tend to rule that one out for now.

In any case, I can hear the clicking noise when turning on of the front wheels. Due to resistance presented by the transfer case and so on the driveshafts do not turn, but the opposite wheel turns in the opposite direction. Now, I can not be certain that the faint sound I hear is the same as what I am hearing when I coast of course.

I guess my best bet is to remove the front drive shaft and take the car for a spin? Not certain the VC is meant to be loaded up like that for prolonged periods of time but at least I can rule the UJ's out.

Cheers,
-P

CV joint?

Clicking sound is a giveaway, from the front is a giveaway, from the centre of front wheels is a giveaway, at a roundabout is a giveaway.

DL

So, it has been a while. Work and all...

Anyway, I finally got the old gal up on the hoist and started poking around. I could not feel any play by hand but I drained the oil from the front diff and disconnected the front driveshaft just to have a look and noticed the nuts wee very loose. So, somehow the nylock nuts have rattled loose or were never tight to begin with. I checked at the transfercase end and all was fine.

Off I went (after filling the diff back up with fresh oil) on a test drive and I could not hear much until I was nearly back home and everything had heated up. slightly annoyed I drove back up the hoist to poke around once more and found the noise at the front was definitely gone but the rear was now the suspect. It makes me wonder if the front was never really suspect after all... I also checked the (nylock) nuts at the rear diff end and sure enough they were not as tight as they could be. However, the "ticking" noise when turning a wheel persists after tightening them. Since there are no CV's at the rear and the UJ does not turn (the opposite wheel simply turns in the opposite direction with the wheels of the ground of course) it can't be that.

I do hear some more noise from the rear right wheel bearing so that is suspect but it does not explain the ticking in my opinion. I would be a bit of a shame removing the diff just to have it out and not see a bloody thing probably since I am no expert on diffs so I am kinda at a loss as to what to test next to narrow this down.

Thoughts anyone?
-P

I recently replaced my rear output seal and removed the rear driveshaft for access on my 2002 D2 TD5 auto..
I turned the diff to get access to the donut bolts and heard a rattling sound in the diff.
It only happened when I turned the RH wheel backwards.
My assumption is that it is caused by the sun gears rotating in reverse and having a lot of backlash.

There was no noise in forward motion. So my assumption is that it is probably relatively normal in an old diff, as there is very little swarf on the magnetic plug and all that is there is paste rather than bits. An interesting (to me anyway) aside to this is that I use a 50/50 mix of 80/90 and 90/120 in the rear diff and had 80/90 in the front and there was a lot more paste in the front than the back. I reckon they can get pretty hot at times.

The main point of failure in these diffs is the sungear shaft spitting out the circlip and then striking the case.

So , ask yourself. Have I spun a front or rear wheel excessively when the red mist has descended?
Regards PhilipA
BTW to ch3eck the CVs , you just put her on full lock and accelerate a bit. You will soon know if you have a dud CV. I recall my son bought a Jackeroo at one stage and did not know to check. I locked the hubs and put it on full lock and was greeted by the most noticeable racket of clackity clacking.

One thing I'll mention in response to Philip is that the Rover diff runs relatively cool as it's a spiral bevel design, there's no hypoid offset.
An xW-90 is more than sufficient viscosity for one, there's no need to go with a heavier oil.
All a heavier oil will do is increase drag/fuel consumption and can lead to a lack of lube to the pinion bearings in cold weather as it can take a minute or two to climb the crown wheel, spin off and get to the front bearing

The Sals on an older 110/130 can run bloody hot though, an xW-110 or 140 works well, especially if using an HD cover which traps the heat.

I'm not sure why you've but less paste on the rear magnet compared to the front, but I dont think it's viscosity related.

Rick I hear what you say but I found that on a hot day say 32C or more , towing my camper at say 900Kg I started to get noise from the front diff when I exceeded say 120Kmh to run up to a long climb. This to me suggested lubrication failure. I run 80/90 full synthetic in my transfer with an extended sump.

I plan to go to Queensland "shortly" ie when the lockdown ends. I doubt whether the fuel consumption will change much.

It was interesting that the wonka wonka sound only came from the front diff and at high load accelerating with 900kg on the back at 32C plus.

Seeing I plan a Kimberley trip next year I feel the 50/50 mix is justified and cannot do any harm. After all the CVs run grease and in RRCs the hubs went from ep90 to grease.

Regards PhilipA