I recently changed the transfer case oil on my LR3 and as I do not have a local LR dealer I opted for Royal Purple Synchromax as has been mentioned on this forum as an alternative. The old old was darker than fresh oil, but not overly so, nothing I would consider as a problem.

Since the change I've noticed an increasing level of noise and 'feel' of vibration through the steering wheel and body. Its was initially more noticeable when you let off and coasted and is a repetitive low frequency humm humm humm humm, but is now increasingly heard when accelerating. To me it sounds like a bearing is starting to suffer from brinelling or a heavy weight gear is starting to wear in one section.

I'm confident its not a wheel bearing as the frequency rate of the noise does not increase or even match with the road speed of the wheels, which leads me to believe it may be the transfer case or poss one of the diffs or some other bearing in the drive train. Its also not the typical sort of wheel bearing failing noise - had plenty of those over the years to know.

The diff oils were also changed a couple of months ago and the old oil was spotless,even though the plugs were really rusted, which led me to conclude they had not been changed in a long while.

I'm going to drain the transfer case again this weekend, but has anyone else had this sort of issue, especially when they used Royal Purple? I have orderred the correct oil for the transfer case now too, just to be sure. Im also going to place a neodymium magnet on the drain plug, so hopefully it will catch anything in the oil as the drain plug is not magnetic, unlike the diffs.

I did look at the price of a new TC and spat out my coffee, so if at all possible I would tear the case down - if and when it comes to that and replace any work parts - again, has anyone done this.

Cheers

 

have you checked your carrier bearing on the rear driveshaft? That rubber surround can fail and cause some weird vibes

 

Never had problems with RP

 

Good point on the drive shaft bearing rubber damper... mine was split and needed replacing when I got the truck. Easy and cheap to check anyways...

 

Thanks guys and yes I checked the bearing - nice and solid, no play. I'll change out the transfer oil this weekend, but found out there is actually an internal magnet in the casing and you can't get to it unless you take the case apart. Seems a strange thing to do when the diffs have mag plugs - ah well Landrover logic I guess.

 

I used Royal Purple Syncromax when I did all the fluids on mine. No problems what so ever after about 4000 miles.

 

Well, I've put a nice strong magnet on the drain plug and will give it a few days before I see if there is anything in the oil. I'll do the diffs after to see if they have anything in the oil too.

 

When I did my first Diff fluid change, looking at the drain plugs I wondered if there was any gears left...

 

well did the rear diff on the weekend and only some very minor sludge, which is what I hoped for given the oil was only changed about 4 months ago.


Front diff this weekend along with the transfer case.

 

I’ll be curious if it quiets down with the OEM fluid in the transfer case. I changed mine to AUTOTRAK II from GM because I had several quarts left over from my Avalanche and it seemed to be cross referenced to Royal Purple. Seems like I notice gear whine a bit more now. Could be in my head. The transfer case works great off-road, so no issues with the clutches. My diff fluids looked like chocolate milk.