Hi Lad's,
As part of my Fathers Day wish, I asked that I be spared from visiting my inlaws yesterday(why didn't I think of this sooner!),so I spent the afternoon doing a little servicing to my truck.I've been listening to a lot of banter on this forumabout which oil is best and what weight to use,so I thought I would come up with my own blend for the heck of it. Here is what I came up with for the "Ultimate Discovery IIOil Service".5 litres Amsoil 10w30 full synthetic,1 litre Royal Purple 10w40 full synthetic,K&N HP2004 oil filter,1 LR OEM drain plugcrush washer and one can of Krown T40 spray lube for the hinges,latches and locks.I'm running a K&N air filter,so Ididn't have todo anything with that yet.6 litres will bring you just a tad over the "full" mark after you run the engine,but that's where I like to keep my oil level.I call this "tad"margin the drip zone.Myengine runs as quiet as a mouse and as smooth as silk. The parts and material cost was about $75cdn.

 

I wouldn't have mixed viscosities of the the oils...

 

No reason to mix viscosities. I don't think that it's to big a deal though using 10-30, 10-40. You'll wanna dump the K&N air filter though. It will kill your MAF sensor.

 

I really don't think its going to make any difference whatsoever considering the 10w40 was basicly used as a topper,but as a rule you're right.

 

I hear that quite a lot about the K&N air filter,but I've had it in the Discovery for almost three years now without a problem.I asked the K&N rep. about that concern and was told;(quote)"if any Oem sensor failure is attributed to the use of one of our filters,we will refund the purchase price of that filter and reimburse you for parts and labour".I figure I'm covered if something were to happen. Take a look at the K&Nwebsite,they have lots of information in their FAQ'S section about this concern.It's really quite interesting to read.

 

Interesting.

 

Well, don't say that RP killed your engine if something happens...Different viscosities will work against each other, breaking down the oil. You are just wasting oil. You said you had a case in the garage, why not just run full RP and save the Amsoil for winter? Topper or not, it is still 1/6 of your total oil. I would not do it.

Good Luck.

PS, I have seen (not heard of) 2 MAF's blown by a K&N. If you have a good relationship with your rep, you should be ok. As long as they are going to pay for your new one.

 

Just what could happen by adding 1 litre of 10w40 to 5 litres of 10w30? Is the engine going to blow up? I don't understand.How the heck can the two oils work against each other after they have mixed together? I've basicly just raised the viscosity of the Amsoil by a point or two thats all. I didn't mix 5w50 with 15w40 or mix a cocktail of different weights.The two weights I used are basicly the same and both synthetic.Why are you trying to cast doubt or convince me that I've done something horrible here? As for the K&N urban myth? poppycock! I've never had an issue with K&N in any of my vehicles ever.If you have seen a MAF sensor contaminated by oil,its not from the K&N filter.Chances are its blow by from the engine itself thats killing the MAF or just a plain faulty MAF.It's impossible for the K&N to let any spotting though its filtration system. Do yourself a favor(and me too),go to the K&N website and do some reading.Pay attention to the FAQ's page and read up on the tests that disprove the urban myth.You seem like a reasonable guy to me,so listen to what K&N has to say.

 

First off, I have been to the K&N website to see what they had to say. My truck came with a K&N when I bought it. I took it off, used a paper filter, and saw no drop in anything. I am not sure how you could get blowby on the MAF, unless you mean an engine leaking so bad externally that it was sucked into the intake. There is nothing before it. Filter, MAF, Throttle body.....The PCV is behind the MAF.

I didn't mean to scare you with what I said. I just didn't want people to read your post and think it was ok to mix viscosities. I called the plant in TX and asked the engineers if it was ok to mix even slightly different viscosities. They are not the same, so they do not mix. Multiviscosity oils are blended through a refining process. They don't just take 10W and mix it with 40W to make 10W40. I am sure you know that. I am not a petroleum engineer, and I can not tell you why it is bad. I don't really care about it that much. You can mix whatever you want to.

It sounds like you got upset, that was not my intention at all. I figure the reason people post on here is to help others based on their personal experiences. I have been told all of my life not to mix viscosities. I have never wanted to try it, not sure why you would. I have seen 2 friends with bad MAFS on disco's that worked fine for 40k and 90K and they both died within 3K of putting the K&N on. DiscoMike worked for Rover, to me he is a rep and the guru on here. That is enough for me not to run one. Seeing my friends lose MAFs for no other reason is enough for me to pull them off their trucks.

FYI, I took my old K&M out to the driveway. I poured some used oil I had on the filter and it leaked right through. You can tell me it is impossible for oil to get through, but I will never believe you.

Again, no miscontent meant here. Just voicing my opinion.

 

Of coarse oil will pour through a K&N,thats not what I meant.I was talking about the impregnated oil that is applied to the K&N filter itself getting sucked through the filter and into the MAF sensor...its impossible.As for the mixing oil issue,yes you're correct,mixing oils is not a good practice,but in my case no harm will ever come of it.As I said,I used the Purple as a topper.There is enough Amsoil in there to protect the engine from the damage caused by the RP!(touche'!) I've contacted K&N and asked if they would have one of their people drop by our forum for a Q&A.Hopefully after that we can put the matter to rest.I believe in K&N just like you believe in Royal Purple.