Rotational Rumble when turning left

Hello all, this is my first post on this forum, be gentle.

A couple of months ago we purchased a 2006 Freelander TD4 Freestyle Automatic, mainly because we needed something a bit bigger than our Fiesta that we would use for very occasional towing and generally moving stuff about. I also have always wante a Land Rover as my familiy always had them right from Series 3 up to Discovery, I'm used to all the normal land rover faults. It also has occasional off road use. We are pretty pleased with it on the whole. It has done 70k miles and has a full Land Rover main dealer service history. We did a VERY thorogh test drive before buying it. I also research all the forums to get an idea of the main issues, this is why we went for one at the very end of the production run so hopefully any IRD / VCU issues were resolved by the ratio changes. Since getting it we had to have a rear diff oil seal and window regulator replaed, both done under warranty. The rear diff had a slight oil leak, nothing bad but I wanted it sorted. Since getting it I have also changed the crankcase breather following a search on hear after we noticed a small puff of smoke with putting it in reverse. We've also put 4 new tyres on it.

We have now come accross a strange issue that I hope someone on here can help with me. I have noticed a "rotational" type rumbling sound coming from underneath the viehicle (under the gear selector) when turning left at anything over about 15 mph. It only lasts for a very short time, just as you put the power on. You can also feel the rumbling through the floor. It does not seem to do it if turning right in the same way. Its most noticeable on tight roundabouts.

I have tested the VCU as best I can. The car is not holding back at all, the rear wheels kick up when turning tight on a loose surface and there are no worrying noises when driving. Its not down on power an pulls just fine. It coasts down hill with no bad noises at all. After a fairly long run the VCU is not hot to touch, its hardly even warm however the IRD definately is very hot. After spending some time under it this afternoon I've found the following:

There is a slight oil leak on the IRD, very small. Garage saw it when they did the rear diff and said it was nothing to worry about for now.

I can twist the prop shaft between the IRD and the VCU as there is some slight play in it. Is this normal?

There is some play in the driver's side rear drive shaft, but nothing major.

The propshaft has a rubber bush on it in front of the VCU which I guess is an outer bush for the VCU support bearing, there is loads of play on this where it meats the bracket that holds it to the floor of the car.

After looking at all this my first though was that we've bought one with a fubared IRD, however other than it being hot there are none of the other IRD failiure symptoms descirbed on here present.

So, all I can think of is that a prophsft support bearing is worn and this only shows when turning left as this is the most common direction to turn tightly at speed. Or it could be the rubber bush in front of the VCU.

Any ideas anyone??? We've got to take it on a very long run at the end of next month and I don't want something going bang on the motorway.

Thanks all

Sorry, forgot to add that the rumbling was there before we put the new tyres on an after. I've ruled out anything like CV boots / joints as the rumble is coming from the centre of the car.

Hello again,

Just been out to do some more testing. I c*cked up first time I posted. The rumble only happens when turning sharply RIGHT at anything over 15 mph. Nothing at all when turning left.

After doing a bit more reading up on it am thinking this might be a front driveshaft bearing problem.

Any help, much appriciated

I wouldn't worry about the IRD getting hot, there is an 'oil cooler' built into it that the engine's coolant flows through. This acts not just as a cooler, but as a heater to bring the IRD up to the same temp as the engine.

Its very difficult to diagnose rumbling issues on the forum, my thoughts though would be the VCU support bearings.

It may be worth changing the oil in the IRD though. If there is a leak, it will ensure it is up to level and you can see how much has been lost, plus it will give you an indication of the IRD's health - ie if it comes out grey, that is the residue from worn bearings. If it comes out still looking like oil, then all should be fine.

Also, pop over to Introduce Yourself - Land Rover Zone and leave a message - its forum etiquette/polite.

Thanks GrumpyGel, have been and introduced myself now.

Have read up and had a look at the IRD and can see the oil cooler you arragement. Our old Mazda Bongo had something similar on its auto box.

I'm definately thinking its something bearing related. Either VCU support as you say, or one of the front driveshafts. The trouble is it doesn't always do it. I think I'm going to have to leave it for a couple more weeks to see if it gets worse so I can locate it properly.

Was planning to do an IRD oil change as soon as I can find time. It had a 50k type service at the main dealer before we bought it so I would have hoped they'd have done it, but you never know.

Also, I've read loads about VCUs and IRDs failiing, is this also common on the very last FL1's like ours? I've heard of some going way past 100k with no issues at all. As ours has now done 70k should I look to change the VCU just to be sure?

new tyres at back?

check vcu

Its just had 4 new Yokohama's all round. It had Pirelli scorpions on before, but they're a tad pricey for me just now.

The VCU seems fine as far as I can tell. Its not getting hot at all, the vehicle isn't holding back in forward or reverse and the rear wheels kick up on loose surfaces and mud. It doesn't seem to be scrubbing tyres and the MPG is pretty good. Is it worth doing the full VCU test?

There's no harm doing the 1 wheel up test described in the FAQ - but it sounds like your VCU is fine. I feel tyres are a worse killer of the transmission than the VCU and you've got that in order.

Mileage is absolutely no indication of impending doom. If you're tyres are OK and there's no tell-tale wind up slowing the car on (reverse) full lock - you're probably fine, but the 1 wheel up test should give peace of mind. LR recommend replacing the VCU every 70K, but I recon that if it ain't broke, don't fix it with something that might!

That's what I thought. I'm giving my bro a hand with his L200 tomorrow so whilst we're at it we might do the test, just to be sure

IanTeign said:

Its just had 4 new Yokohama's all round. It had Pirelli scorpions on before, but they're a tad pricey for me just now.

The VCU seems fine as far as I can tell. Its not getting hot at all, the vehicle isn't holding back in forward or reverse and the rear wheels kick up on loose surfaces and mud. It doesn't seem to be scrubbing tyres and the MPG is pretty good. Is it worth doing the full VCU test?

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It has to get hot to work propper.

That's what I thought originally, but some of the advice on here suggested otherwise. It does get warm, but not so hot that you can't keep your hand on it.

If it was the VCU I would have thought I'd get trouble al the time, rather than when just turning right??

Read the vcu article in the cfaq section.

I tend to agree.

Father in laws TD4 now on 200000 plus still on factory fitted VCU

Hi

My 2001 Td4 Auto also has a grumble from the transmission at the front when cornering right, it's done this since I've had it which is just over a year. The noise isn't as noticeable when it's up to normal running temperature, hence why I never noticed it on the test drive as the previous owner must have been out in the car before we turned up as it was slightly warm. I removed the prop just incase it was the VCU causing it, but it was still the same. I've also replaced the VCU and support bearings with new GKN items while the prop was off basically because the mileage was 122k and it was one less thing to worry about. My thoughts on the grumbling noise on my FL when turning right is that it could be the front diff whining? My service is due so going to change the diff oils to see if it quietens it down when cold.

Does yours quieten once it's up to temp?

We've been out and about in it all day to today and done some more testing.

Yes, it does get quieter as it warms up. I did the one wheel up test and the full lock reverse test, all ok. No problems at all. I was thinking it might be diff too.

My bro and I spent ages underneath it checking everything. The only thing we could find is some slight play in the UJ where the propshaft joins the IRD and a tiny amount of play in the prop shaft support bearing in front of the VCU. In both cases the play was just over a mm at the most.

Driving home it only did it once and that was on a tight roundabout, cornering right.

Thanks for the the info, its reasurring that others have had the same thing. And that factory fitted VCUs can go on so long, I don't think I'll change it just yet.

If it gets worse I think I'll replace the support bearings as suggested as that seems to be the only thing it could be.

if its only when turning right id suspect lh wheel bearing, any play in a uj and joint is buggered

I wondered if it was a wheel bearing, but would that cause the rumbling to occour in the centre of the vehicle?

The play seems to be where the UJ meets the IRD. Could that be a bearing in the IRD?

its easy enough to see if plays in uj or ird flange , ird flange should have rotational play just no other ie up/down in /out, noise can travel its often difficult to pin point it from inside car