Grinding sound

[Mpowerrob]

Hi all, newbie hear.

I've had my car e53 X5 for 3 years now and had no problems until recently I stated getting the 4x4 light on and occasionally 4x4 and traction light together, I changed the cog in the transfer case hoping this would solve it but it didn't to be fair the original cog was not worn, I've stated getting a grinding sound coming from the font of the car especially when turning more so when turning to the left.

If I diconect the transfer case electrical plug and go for a drive the grinding sound disappears?

Any ideas would be greatly appreciated 

[X5Sport]

Sounds possibly like a front diff issue if it disappears when the fuse is removed from the AWD transfer case.  That would change the loading on the system meaning the sound might vanish.

Have you changed anything else....like the tyres?  Do you have a large tread depth variation front/rear?

It may not be your issue, but could be a source and needs eliminating, but do you have the identical make of tyre on all corners and are they one of the BMW ‘*’ marked (and therefore meet BMW Specs) variants?  Broken diffs caused by incorrect tyre use in the past and/or by previous owners is something showing up more frequently now these cars are aging.  These cars are intolerant of both large depth difference and certain tyre choices, especially on ‘staggered’ wheel sets.

kkx5 is the best one to answer transmission queries with these diffs and transfer cases.

[Silverfox58]

Hi this might  not be the  answer  but this happened  to my car and it was dry drive shafts,I put new gaters and filled  with grease  and it's gone , now I'm not saying this is the same as yours but it's a thought.

[Mpowerrob]

Anyone?

[Alan Gunn]

[quote="Mpowerrob"]
Anyone?
[/quote]
As asked before what tyres and tread depth's are on them.
Are they all the same brand and size.

[Mpowerrob]

Hi guys thank you very much for your replays so far

The tyres are the same all round make is Nokian they look like winter style tyres sizes are 255/50/19 front and 285/45/19 rear treads are similar front and back with the fronts starting to wear on the outside edges.

The car has also started to shunt very slightly when coming to a stop in traffic.

[Horizon]

My X3 was doing the shunting bit when coming to a stop,  on the way back from picking her up, you could actually feel the tyre slip a little as it was raining . I had pre ordered tyres for mine, as I've read all the horror stories over in correct tyres.
I'd noticed on my inspection/ testdrive that it had 3 different makes of tyres on her, so whilst they were Servicing MOTing it that week I ordered new tyres.
As soon as I fitted the new tyres all the noises and shunting and slipping went away
I read up quite a bit on rolling circumferences of tyres and all manufactures have a data sheet with sizes / profiles revolutions per mile.
After looking at these I could see the massive difference in how many revolutions  per mile say a 255/50/19 and a 285/45/19 are in the same make of tyre.
Don't be fouled into thinking  the same make on a staggered setup is anywhere near the same rolling circumference
As my X3 rims were only 1/2 difference in widths front to rear on my staggered setup, I  checked the industries standard wheel to tyre width chart and found my 255/40 /19 rear size was also compatable to fit on my front rims too, so I have 255/40/19 all round, identical tyres.
Unfortunately E53 X5 has too much a difference in width front to rear to allow this.

[X5Sport]

One of our members had this on a front diff which was also jerky on full lock at walking pace.  If you have the same then you may need a new front diff if the damage has gone too far.

Tyres may be a contributory factor as they aren’t ‘*’ rated, or on BMW’s Approved list. 

If the overall circumference is now more than 1.5% different (measure with a piece of string) front to rear then that can upset the diff too.

Several members on here have previously reported grinding noises which only went away once the tyres were replaced with the approve types.  These cars do not like certain tyre brands.

[Mpowerrob]

Any ideas why it only makes the grinding noise when turning left?

It's definitely from the front drivetrain as when I disconnect the plug to the transfer case, so only rear wheels are being driven, the grinding and shunting is completely gone, should I leave it disconnected to stop further damage?

Can you guys recommend a good tyre to buy without breaking the bank?

[henrym3]

It would be interesting if you had the time and a nice flat level surface to put a chalk mark on all four tyres at floor level, mark the floor as well, move the vehicle forward a wheel rotation then mark the floor again, then measure the distance between chalk marks.

[X5Sport]

The noise will depend upon the drive load and as it’s now effectively freewheeling the drive load is off.

Tyre wise, you are looking at between £850 and £1,200 for a set of the right tyre type - a little less for non-RFT.

Fitted tyres are Bridgestone, Dunlop, Continental, Pirelli and Michelin.  You will need the versions with the ‘*’ marking on the sidewall. 

To avoid transmission failures unfortunately you need to stay with one of those makes as the versions are made for BMW cars (Audi and Merc also have their own now).  More than a few of us have discovered that these cars are expensive ladies to run.

You don’t need to stick with RFTs though and there are ‘*’ marked versions of non-RFT available.

You might to also get the front propshaft checked for excessive play.

[henrym3]

I just stuck those sizes of tyres into a online calculator and it shows that the rear tyres will do 2 revolutions less per mile than the front ones. Don't know now significant that is on an E70. As X5Sport says even that will load up the diff somewhat.

[Mpowerrob]

Bit confused so what tyre sizes should I go with as going to get new tyres this week are the 255/50/19 & 285/45/19 the wrong size and one of the reasons for the cause of my problems?

[X5Sport]

The correct tyre sizes for BMW rims are shown on the B-pillar tyre pressure sticker.  It lists all of the Approved front and rear wheel sizes, tyre sizes and Load Index ratings for your car type.  As long as you have BMW rims then you shouldn’t go wrong.

The sizes you list are both correct if you have a staggered wheel set up (the E53 with 19” is staggered) BUT if not using ‘*’ marked tyres then the overall tyre diameter could be different and therefore the circumference of the rear tyres could be as much as 32mm different.  With ‘*’ marked tyres the diameters (and therefore circumferences) are tweaked to be matched to less than 1.5% resulting in no transmission wind up occurring.

What you may have is different circumferences leading to transmission wind up leading to overstressed differentials or transfer boxes.  This really matters on xDrive equipped cars with staggered setups.

You rear 19” rims should be wider than your front hence using the wider tyre tread (285mm) but lower height to width ratio (45%) to match the circumferences front to rear.  ‘*’ marked tyres when new are made to ensure the match is correct.

If you have the same size/width rims front and back then all four corners should have identical sized tyres

[Mpowerrob]

Ok thought I’d update, so I’ve changed the wheels and tyres to original 17” with bmw stared tyres and the ride is so much smoother however I still have the grinding, have taken it to a transmission specialist and they’ve had the car for 2 weeks investigating! Trying to find the problem they’ve now taken the transfer case of as codes were saying transfer case, they’ve changed the transfer case clutch pack? as it was worn they’ve said the grinding has now gone, but the 4x4 is still on and they reckon they’ve got a code for the abs system ?? :cry1: :cry1:

Any one shed any info as im starting to throw money at a car that’s not worth that much. Help please