Newbie with 4.6IS questions!

[Sniffer]

Hi Guys,

As someone who has acquired an E53 4.6IS X5 in the last couple of months I have been lurking on here a few times since

The vehicle in question is a two previous owner 2002 model in Estoril Blue - I`ve always wanted one and as it ticked all the boxes (AWD for the harsh Canadian winters, Winter tyres on smaller 18" wheels of the same style, desirable model, good colour, good history - previous owner took good care) I took the plunge

I now have some questions:

I find the ride "harsh" - now I know that the 4.6IS was breathed on by Alpina to make it more sporty but the ride is not comfortable IMO - I definitely expected better considering it has air suspension, my buddy had a Range Rover Sport with standard air suspension and the ride was amazing - is this something X5 owners simply have to deal with or is something wrong?

I find their to be a steady "drone" or "whine" (which increases with speed - noticeable from 60KM/H up) which I initially attributed to the standard 20" tyres being almost worn out but after fitting the smaller 18" with the softer snow tyres the noise is still there - is this normal or should I be thinking gearbox (which shifts just fine)/driveshafts/wheel bearings?

The vehicle has lost a little coolant (is this normal - I`ve NEVER had to do this to any vehicle Ive owned before) and I`m about to top it up - can I use this antifreeze? Clicky Ive heard horror stories about using the wrong type and the effect it can have on certain types of metal, I also remember someone saying that mixing two different types (specifically colours) can neutralise the antifreeze effect - is this true or am I worrying unnecessarily?

What the general consensus for service intervals on these vehicles? Ive always looked after my stuff and this vehicle will be no different

Thanks in advance!

[Ricky Bobby]

To answer your questions


1) 4.6iS only has rear air susp. Not sure what you call harsh, but I have 2-axle air susp on my '03, with factory staggered 20" wheels/tires, and find the ride wonderful. Granted, its not cushy like a Cadillac, but sporty. Maybe you have some excessively worn parts on the suspension needing replacing?

2) If you had bad wheel bearings you'd know it, its not a whine, its like the drone of a WWII bomber jet above 40 mph. If it were me, I'd be replacing fluids in the diffs front and rear as well as the Transfer case given the age of the vehicle, to rule out any excessive drivetrain whine. Are you sure you're not low on P/S fluid and hearing steering whine from the rack? I don't have nor have driven a 4.6 to know if the engine has a characteristic whine or not. Also check oil level as that will make the engine louder if it is low. Hows your alternator doing ? (OBC test 9)

3) Only use BMW coolant, it comes in a gallon but needs to be diluted 1:1 with distilled water. So technically, one gallon of BMW coolant makes 2 gallons of ready to use coolant.


Tell us what you have serviced before on the X after purchasing, the current odometer reading on your X, and any service it had/receipts the previous owner gave you before selling it to you, would give us a fair perspective of what you need to do maintenance wise and preventatively to avoid failures down the road.

[TwinTurboGTR]

I concur with what RB is saying. You need to be a bit more specific on "harsh" Some say a harsh ride is driving a Porsche 911 C4 and some say it is elegant in its own right.

As for the whine... is that relative to vehicle speed or the noise is constant?

Coolant wise... stick with BMW coolant. Dealers change $20 to $25 for the liquid, but it gives you two gallons which is roughly $10 a gallon. Prestone is what $18.99 at AAP and AZ? Just spend the little extra and get the right stuff.

As for you losing coolant... you will need to do some searching. Obviously check for leaks around the expansion tank and hoses... If there is nothing you can see leaking, get under it and look by the transmission bellhousing. If you see greenish/blue crust... you very well may have a valley pan gasket leak down the middle of your motor. Which in that case, will progressively get worse as you continue to drive. If you look in the "articles" section, I made a DIY on the Valley pan gasket replacement...

Also, please put your X's info in your signature such as I and RB has. It will make it easier for people on the forum to I'd your problem better.

[racingbmwm3]

4.6iS is designed for better handling. It's the unofficial //M version of the X5. The X5 already being designed for handling well on paved roads, giving up any notion of off-roading. Thus, the SAV moniker and not SUV. So, the ride will be a little harsher than most cars and SUV's. But, my Mini with stock suspension rides harsher than our 4.6.
Before trying to decide that something is wrong with the suspension, do you have receipts of all the repairs/upgrades done by the PO? It's possible the suspension has been 'upgraded' to something with even better handling than stock, which would definitely make a harsh ride.
If not, then worn suspension will make it uncomfortable. You haven't mentioned how many miles you have.

A noise that increases with speed will have to be something between the transmission and wheels. Ricky Bobby is correct, if the fluids haven't been changed in the last couple years, all the diff fluids should be done now, or at least checked. May need to get the vehicle onto a lift with someone in the car to 'drive' the vehicle and someone underneath to listen for the sound. DSC will need to be turned off...

11 years old, if cooling system components haven't been replaced yet, it is time. Could be: radiator, expansion tank, valley pan, waterpump, transmission cooler-radiator sealing rings, or radiator hoses. And typically, if you replace any of these parts, others will start leaking soon (either immediately or within weeks), so its a good idea to do it all. Then you'll get another 10 years of coolant reliability.
Yes, use BMW coolant. In the end, its about the same price as the 'cheap' stuff at the parts store because those are premixed so you have to buy twice as many. You'll need at least 2 gallons for most major cooling system repairs.

I would only expect to need to add maybe a cup or two of coolant at an oil change (5-7k miles). More than that is less time means a problem. Same deal with oil.