Hot vcu advice please !

Hi, some advice please, I'v just been out for a run and noticed a drone between 60/70 mph. I decided to have a look under the car and found that the VCU was hot to touch. Does this mean my VCU is goosed?
My milage is 57k, Thanx in advance

Hi Ian,
they get warm but not usually hot-are your tyre sizes exact same front and back? how's tread on all wheels? something's causing your VCU to overwork...check it out soon before you overwork your diff or IRD matey.

joe27979 said:

Hi Ian,
they get warm but not usually hot-are your tyre sizes exact same front and back? how's tread on all wheels? something's causing your VCU to overwork...check it out soon before you overwork your diff or IRD matey.

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Thanx for the reply Joe tyres onthe front were on the car when i bought it 18 months ago and have given no problem. Tread is fine have recently replaced the rear pair with latitudes.Could the cause of the drone be incorrect balance?

Due to how the Freelander transmission works, wiff the front wheels turning slightly faster than the rears, you need to have the same size tyres all round. If you change any, then they need to be done in axle pairs. New ones to the rear always.

You say you’ve replaced the 2 at the rear. Are they the same size as those at the front? Also different makes can have slightly different diameter (therefore circumference too). The greater the difference, the more stress on your transmission causing the vcu to work harder in effect. This puts more stress on the ird and rear diff.

The test below in my sig will allow you to test your vcu to see what it’s doing.

because they thought freelander owners would be used to front wheel drive

Slightly different sized tyres will mean the VCU has to do some work on the straights,
especially at speed. If the VCU fluid is starting to get old it will put a lot more strain on the IRD and rear diff and cause premature tyre wear. If the VCU has never been replaced 57k might be a good time to change it. £300 now rather than a much bigger bill in 6 months.

Thanks for the replies chaps does a worn VCU make the droning sound at speed ? the car drives nomaly under 60 i am thinking 2 new tyres so they all match and a VCU is on the cards any more advice on the cause of the drone would be appreciated i j

A tired VCU won't make a noise, it'll put more strain on the rear diff and IRD so any wear in these will be be more noticeable (and be getting worse )

Drone could be your rear tyres cutting in a "saw tooth" shape due to the VCU.

Droning on mine was worn VCU support bearings...which you should replace when you get a new vcu, most VCU's will or should come with new support bearings - make sure they do :O)

joe27979 said:

Drone could be your rear tyres cutting in a "saw tooth" shape due to the VCU.

Droning on mine was worn VCU support bearings...which you should replace when you get a new vcu, most VCU's will or should come with new support bearings - make sure they do :O)

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Hi just a update today i mesured my tyres and found that the front pair were 25mm shorter in height than the rear pair i hope this is the cause of my problam :doh:

just done 268 miles on a recon vcu and i'd say it quite warm not hot but very warm no noise or droning noticed.
speeds up to 90 but mainly 70 mph.
60 miles was town driving rest motorway and "A" roads if this helps

p.s got 41mpg too not bad me thinks

Hi and thanx to the members that gave advice. This is an update fitted two new Michelin Latitude Tyres on the rear, moved the nearly new Latitudes form the rear to the front. Took the car on a 55 mile run no more drone and VCU was warm (not hot).
When I bought the car from a National dealer they had put 2 new budget tyres on the front. I think it was just luck that the original Michelin's were worn right down on the rear and gave no problems, problems only started once I replaced the rear tyres. A height differance of 25mm from front to rear, Which is now just 2mm in differance.
The car drives a lot better with proper tyres on the front will keep an eye on the VCU I think future advice to all Freelander owners is to fit 4 tyres of the same make and size. They say ignorance is bliss !

Hi

Just changed mine a few days ago. Speaking to Bell engineering before I got the new VCU to ask how to test a worn VCU. They said, one way was to go for a 12 mile drive and see if the VCU got hot. If very hot, it could be on the way out.

Hope this helps

the VCU gets hot when it is working. Have you done the VCU checks in the FAQ section?