too funny man

 

no way . no way . no way . i'm p!ssed if i burn a quart in 5000 miles .

 

Yes - it did turn into a "geek exercise", that's for sure. But MrCooperS' post about adding a quart of oil every 1,000 miles got me wondering if there might not be some benefit to periodically draining/replacing only a portion of the car's oil, rather than the conventional method of draining/replacing it all at once.

I originally used a huge Excel spreadsheet to generate those figures for the average age of the oil in his crankcase over 50,000 miles, as well as the breakdown of how much oil in his car was 1,000 miles old, how much was 2,000 miles old, etcetera.

Then, I recognized the pattern and was able to come up with a formula rather than having to use the spreadsheet. Basically, over tens of thousands of miles, if you drain/replace one quart every 1,000 miles, the average age of the oil in the car will stabilize at 3,500 miles, which is well within the usable lifespan of the oil. Of course, you're using as much oil as if you were doing a full change every 4,500 miles, which might be considered excessive.

So, I changed it to adding one quart every 2,000 miles, which is equivalent to doing a full change every 9,000 miles. With this schedule, over time the average age of the oil in the car will stabilize at 7,000 miles. The average will be lower immediately after adding a quart of fresh oil, but it will never go higher than 7,000.

So the question is whether it's better to use the conventional method where you sometimes have all fresh oil and sometimes have all old oil, or to periodically drain/replace a fraction of the oil so it always stays at about the same average age. Of course, doing a partial oil replacement is only going to be feasible if you have an oil extractor or a Fumoto drain valve. Plus, it's going to be much less convenient to be messing with the oil every 1-2k miles.

In short, I don't think the exercise yielded anything earth-shattering, but it was fun to play with.

 

k, so i changed my oil today, at the dealer using there lifts and my stuff.

so when i went to take the bolt off the oil pan i was torquing the wrong way, yea im that dumb. anyways i broke some threads on the bolt, changed the oil and filter, put 2 drops of blue locktite on the bolt, i could get the bolt into the oil pan and torque it a little bit and then it would spin. it's also holding all the oil just fine for right now but monday im going to fix it.

So my question is what size is a 2005 R53 bolt for the oil pan? because im going to get a larger bolt and re-thread the space and have a bmw tech re-thread the bolt for me.

Finally i've already bought the oil extractor from harbor freight so i no longer need to jack up the car and damage/remove the oil pan bolt. good investment.

 

The drain bolt is 14mm with a 1.5mm thread pitch (M14 X 1.5).

 

thanks man.

 

My mini has 53,000 miles on it. I changed my oil about 2500 miles ago and my dipstick is reading about 3/4 full. Is that fine or is it burning oil? I'm running Amsoil Synthetic 5w-30. When I do my oil change next time I will have to check what the oil level is at so I know where it should be at.

 

get the fumoto drain plug!!!!

 

I don't think it's normal for Mini's to burn or use oil unless something wasn't broken in properly or there's a problem. My MCS and another guy's MCS at work don't use more than a couple oz's between oil changes. A bunch of guys on the forums have had similar results too.

FWIW, I used to run Mobil 1 but switched to Amsoil 5w-40 Euro formula for the last couple years with excellent wear readings when I had the oil analyzed (and generally quieter engine for longer). Even with mucho race track use. It's good stuff. This year I decided to try some Renewable Lubricants Inc. HD Biosyn oil in the MCS & another track car after seeing the excellent results a few others obtained from it.

 

I seem to be having similar issues

I was hearing what sounded like a "tractor Noise" / Diesel engine tick that would come and go -- -loudest at cold start and then would go away

It also sounded like a there may have been an isse with exhaust

I took it to the dealer and they could not fing anything -- i insisted they keep it and keep trying ---- nothing happened

I took the car back and sure enough it came back with a vengeance --- at one point the Oil Light came on and I immediately pulled into a station and checked the oil - showed very low - i put in a quart and it quieted down immediately

Back to the dealer and they claim no damage done and that it is normal to burm 1 quart per 750 miles --- they said "keep an eye on it and fill oil as needed" -- they did change the tension belt

Now 2,970 miles later -- the noise is back ---- it seems insane that a 2007 R56 can burn this much oil in 2,970 mile -- i DO NOT drive it hard and it's almost exclusively around town miles -- no visible signs of leaks etc

I'm concerened that seroius damage was done last time and continues to be done -- I hope I don't get past warranty and then have a real issue

Any suggestions will be greatly appreciated

Thanks

 

BHozier,
Your path is clear........
If you in fact do have a latent defect/failure just waiting to mature into some type of caastrophic failure, then your mission is to mature that defect into a full manifestation of the failure while it is still in warranty.

So, drive it like you stole it. Keep the oil level proper, but drive the hell out of it. If it fails, let the dealership fix it, if it lives, then you really know that it is really OK.

 

Thanks for the reply

Do i just adding oil no matter what -- or can i really make an argumet that this is not normal?

It just seems crazy that I have to keep adding oil every 750 miles

 

Definitely keep the oil level proper, but if the oil consumption is 'technically' within spec, then the dealership can and will do nothing. If you can somehow convince them the consumption is say 1qt in 500mi then you have an argument for action on their part.

Good Luck.......

 

I'm having the same problem recently - went to check oil level in May and it wasn't even registering on the dip stick. Because of the long oil change interval I'm not in the habit of checking regularly (my bad) so it could have been like that for months. I did an oil change after I noticed and in the intervening 6 weeks I'm down by ~1/8 of the hatched section on the dip stick. I don't know how far down the level had got when I noticed in May, but now I'm hearing a roughness between 3k and 4k RPM, especially when cold, that makes me wonder if the crank was starved. All of this literally weeks after the warantee expired . Where I would appreciate any feedback is re: possible root causes. There are no obvious external leaks anywhere so I have to assume that I'm burning the oil. I'm also not sure whether there is any point in taking the car in - if there is no way to diagnose the issue then is it worth it? If the worst case happens and the engine does blow, then any advice re: replacement (i.e. new vs. engine from a scrappy)?