e46 sludge issues... 330 followed BMW service intervals...

[SharkmanBMW]

I have had it for a year and done 3 changes, but I dream at night about the sludge and skank that may be in my engine.

I know Bill R or Winfred posted pics of this issue a long while ago (- that I can no longer find here)

My question is:

If for 50k miles my 330 5 speed was serviced as per BMW specs ( )
Then I started using Motul synthetic for 3 changes, now have 65k.

What is the likelihood I have a sludge issue in there?
Is there any way to check?
Is there any additive or something to loosen that **** up before an oil change?

OR, is removal and manual cleaning the only way.

My car shows no signs of problems, but before I do another change, is there anything that can be done to help?

I was told to use oil with as many "cleaning" additives... is this going to help? My Motul has none, great lubrication, but not made with "cleaning" additives.


Suggestions?
Thank you!

[Bill R.]

Auto Rx is frequently used on toyota's with the sludging problem but i don't think yours is that bad. I'd just use mobil one synthetic like i've always said.

Here's part of a service bulletin from Saturn regarding stuck engine rings on the 4 cylinder motors. Notice that they also recommend mobil one to help clean it up. I'd just switch and change your oil more often than the bmw interval

I have had it for a year and done 3 changes, but I dream at night about the sludge and skank that may be in my engine.

I know Bill R or Winfred posted pics of this issue a long while ago (- that I can no longer find here)

My question is:

If for 50k miles my 330 5 speed was serviced as per BMW specs ( )
Then I started using Motul synthetic for 3 changes, now have 65k.

What is the likelihood I have a sludge issue in there?
Is there any way to check?
Is there any additive or something to loosen that **** up before an oil change?

OR, is removal and manual cleaning the only way.

My car shows no signs of problems, but before I do another change, is there anything that can be done to help?

I was told to use oil with as many "cleaning" additives... is this going to help? My Motul has none, great lubrication, but not made with "cleaning" additives.


Suggestions?
Thank you!

[DanDombrowski]

You have about the same service that my 330 3.0 engine has had - got the car at 48k with assumed bmw spec service and I've done 2 oil changes @ 7k miles (Im at 60k now). So far, I haven't done anything but pull the dipstick on this car yet, but it seems to look fine.

Honestly, I'm not worried about it. Think about it this way - how do people usually find out they have sludge? The oil pump light comes on or they get valve clatter. If you don't have that, and you're using a good synthetic on shorter intervals, it has nowhere to go but up, right?

I like all of my engines to be perfect, but if the engines running fine and its only going to get cleaner with good synthetics, you've gotta draw the line somewhere. I wouldn't worry about it.

I need to pull the VC and replace the gasket in the not too distant future. I'll let you know how it looks.

[SharkmanBMW]

Thanks guys,
I will track down M1 here somewhere and get it done every 5k miles after that.

I also need a brake flush, rad flush, full brakes and Rear Lower Control arm on the driver's side plus both bushings!
Any other suggestions? or brands to get or avoid ?

[BillionPa]

actually the M1 you buy now is not the same as before, the base stock formulation has changed to the same that BMW and castrol use in their oils.

for a clean engine you want low SAPS high TBN PAO or ester oil, Mobil1 0W40 would be the easiest to find.

ARX is indeed the best solution to sludge buildup, but you need a dino rinse oil. i used Mobil Clean 5000 with valvoline synpower oil treatment, did a good job.

[winfred]

i wouldn't run any cleaner through it just m1 and let whatever build up there may be slowly disolved

[SharkmanBMW]

Good stuff guys...
M1 it is, which exact model tho?

there are a few choices...
http://www.mobiloil.com/USA-English/...Oils/Oils.aspx

Should I use their "clean" Mobil Clean 7500 or 5000 versions?
Or should I stick with regular M1 ?

Please advise your choice of oil and grade - I fully appreciate your input - your experience is worth a lot, THANKS!

Gracias!

[winfred]

regular old m1 synthetic and fairly thin, 10/30 5/40 whatever blows your skirt up

[BillionPa]

the "clean" ones are not synthetic, but group 2 base.

M1 5W30 and 10W30 are now supposedly fake synthetics like castrol syntec and pennzoil platinum. that doesnt make them bad.... but they charge like, a lot more than pennzoil does for the same thing!!

however it does mean that the cleaning properties of the oil have changed.

my "current" recommendation for sludge removal is a 50/50 mix of M1 0W40 and Redline 5W30, with AutoRX.

of course you would want to first find out if you actually have sludge.

2 places to check for sludge. pull the oil pan. the bottom end should be free, clean crankshaft and rods. also pull the valve cover and take a look at the camshafts.

[winfred]

a little build up of sludge in and of itself is not totally a bad thing, it's not hurting anything where it is on the non wear surfaces, but when you go halfassedly scraping it off you can stir it up and it can clog up the oil pump or other things