drone from rear

[viniu88]

have galant vr4. there is a drone from rear end. i thought it was from the snow tires i had on there originally.

but now have summer wheels and tires on there to test. the noise is the same. it is really noticable above 70mph. it sounds louder under throttle than off throttle but still there.

my friend thinks it is my rear diff as his did similar noise in his rx7.

is there any simple test to see if it is rear diff, centre diff or wheel bearings?

[elnevio]

Does it make more noise going in a straight line, turning left or turning right, or does that make no difference?

Whilst it is not always easy to tell from inside the cabin, the noise coming from the rear would probably rule out the centre diff, which is at the gearbox end.

If the noise changes with direction, this could point to a wheel bearing issue, otherwise yes, possibly a rear diff issue. But it might simply be a case of draining and refilling the diff fluids, especially if the fluid is old and breaking down - but not really a simple check other than dropping the oils to see.

I'm sure the cleverer ones around here might have some other/better pointers/ideas.

[Davezj]

i am breaking my VR4 at the moment and have both rear wheel bearings and a Diff going, but will have to reseal the mid joint on the diff as there is a slight leak from it and i would not want you to have a leaking diff.

thread is here
http://www.clubvr4.com/forum/showthread.php?t=52329

when you diagnose the issue give me a shout and i can sort you out with bits.

[Davezj]

have galant vr4. there is a drone from rear end. i thought it was from the snow tires i had on there originally.

but now have summer wheels and tires on there to test. the noise is the same. it is really noticable above 70mph. it sounds louder under throttle than off throttle but still there.

my friend thinks it is my rear diff as his did similar noise in his rx7.

is there any simple test to see if it is rear diff, centre diff or wheel bearings?

I have just replaced one of rear wheel bearing on the rear, and it is difficult to tell where it is coming from due to the noise being transmitted through all the driveshafts and diff.
as nick says probably the easiest thing to do is check for wheel bearing issue.

Wheel bearing issue,
If the noise is louder when going round a right hand bend it is the left wheel bearing
if it is louder going round a left hand bend then it is the right wheel bearing.

Rear diff issue
Generally louder the faster you go, but this is not true all the time.

Get someone you trust to sit in the back seat of the car and tell you which side the noise is coming from. then get them to drive the same route you get in the back and double check there diagnosis. it makes it much easier to tell where the noise is comming from if your are sat in the back.
Hope this helps.

but do as nick says and try the cheap option first and get the oils changed in the diff, it will cost about £30 for the correct oils 2L atf (AYC side of things clutch pack and Hydraulic fluid.) and 1L gear oil (diff gears) and at least if it is not that then you know the diff has the correct oils in it.

[Danj]

I had the same drone coming from the rear of my Legnum shortly before I sold it, did think it was the wheel bearing and thought no more of it. New German owner has since been in touch - turns out it was the rear diff costing a fair amount to replace!

[elnevio]

... as nick says ... but do as nick says ...

Who?!

[viniu88]

... cant tell if its more noisy turning one way or another ... but its all related with wobly wheels
had that problem for quite long time - done balance 4 times on old wheels - still vibrations on steering wheel - now change wheels to smaller onec and same problem, at 100-110mph it feels like rear start dancing

but there is another thing - never seen AYC bar on, well at start of engine it comes on and off - but then never ever while u driving

[mike74]

but there is another thing - never seen AYC bar on, well at start of engine it comes on and off - but then never ever while u driving

Have you tried going round an empty roundabout (smaller the better) in a low gear & booting it on exit? That should definitely light at least one or two bars up. If not then that may be your issue there...

[elnevio]

Or, drive down a straight road at about 20-30 mph, and (ensuring it's safe to do so of course!) slalom from side to side quite quickly - that should get the green bars lighting up.

[Davezj]

Who?!

sorry nev


my bad!

[viniu88]

done what u guys said abt AYC ... nothing but going sharp in the corners u can feel that rear gives more power - gets u of the corners - so it sims like working but not showing it on dash ...

but another thing when it comes to wobly wheels - when turning right - and steering wheel is at 45 deg vibrations are much less ... sims like front bearing is gone ... gonna change both of them - just in case

also want to change transfer box/diff oil so hope that would sort rear noise

[HPRULZ]

have galant vr4. there is a drone from the rear

I had this too so now I let the wife sit in the front!

Kev