Looking for OEM motor and transmission oil viscosities.

Also, wondering whether you guys think that going to MT-90 will clear up my felt concern that the stock fluid degrades too easily. Up to around 5k after swapping to fresh transmission fluid OEM it feels great...starts to slide downhill rather quickly after that and plateau at a level which...feels chunkier than when fresh. After that, any further impairment on shift feel is much more gradual and subtle.

- Matt

 

Not good when NAM doesn't even know...bah!

- Matt

 

as am I, but I haven't seen much other than subjective banter. Nor have I seen any analysis like what's been done on engine oil....

Matt

 

No joke. I searched through over 300 threads worth of info over at Bobistheoilguy and came up with nil. Closest it got was people recommending 50/50 mixes of MTL and MT-90...no objective statements as to their base ester groups, kinematic viscosities, etc. And I'm having trouble sourcing such information from the manufacturer's themselves.

I'd really like to know whether the stock stuff is a Group III/IV-V blend, or straight synthetic (Group IV & V). Might possibly explain the degradation, although with modern oils even this conclusion is circumspect.

- Matt

 

Good morning. having changed out the oem trans fluid for Redline MT90
at 15k and again at 25k i find that shifting seemed to be alot smoother
from my stand point. and it's one of those maint. items that won't cost
alot do and for myself gives me piece of mind.being here in Socal the weather can get a little warm in the summer time so thats why i went with
the slightly thicker MT90 over MTL. hope this helps.

 

Like Dr. O mentioned above (and I agree), there's a lot of subjective analysis of this, but I am looking for more solid info on the composition of the fluids.

- Matt

 

I too am interested.

 

you might try the Redline web site

 

Pull a sample and have it tested. 30 bucks and you will have the results.

 

Yeah, I was hoping to avoid the $20-25 cost for each thing to be tested, thinking someone might have the answer here. Additionally, I don't run the Mini oil anymore...would hate to have to run out and buy a quart just to get a sample.

- Matt

 

chances are that the manufactor who designed and built the tranny did lost of testing when choosing the correct fluid.

 

Oh, no doubt that it's functional, but like most design decisions cost is a limiting factor. At some point the marginal benefit, to them, doesn't outweigh the marginal cost. I'm chasing the extra %, and don't really care about the price...the extra minor cost to me is obviously quite a bit different than the massive extra cost Mini would have incurred going to fully synthetic, higher quality fluids.

- Matt

 

well i never had an issue with the stuff that came from the factory lol

have 188000 miles on mine it be well over 200,000 now if i didnt store it for the winters bouht it with 4 miles on it, autocross and dragon it regularly drive hard and never changed the fluid still running on the same stuff, shifts like a dream still and the trany is still lock tight and makes no noises, still origanal clutch to boot, but i may want to change the fluid here this coming spring when i change my clutch to a little more agressive one, figure it wouldent hurt !

 

I use the MTL Redline in the tranny every 20K, use the Redline 5/30 every 4500-5000 intervals in engine. Might be switching to Royal Purple as dyno show another 2HP with use. Live in Midwest and use the basics for the lowest and extrme temps. Use this stuff religiously in my 03S and Land Rovers.

 

If we all just accepted the mantra "the manufacturer knows best," the drivetrain modification forum wouldn't exist.

 

From reading a previous thread you started on this subject, you already know the viscosity and group rating etc. for the transmission fluid; you also are familiar with my position on its use. For the rest of the readership here’s my take. MTF-94 is fully synthetic with a very robust and expensive additive package (no cost cutting in the mix). I had a 14,000 mile interval analyzed and the results were outstanding. The analyst, Terry Dyson, was familiar with the original Texaco product and had high praise for the formulation. He commented the fluid as tested could be used indefinitely.

When I installed a Quaife ATB, I tried Silkolene SYN5 for a while but found shifting action slowed. The Silkolene product is top quality but that didn’t mean my gear box would perform well with it. Since I don’t have any problems with my transmission using MTF-94, and the alternative I used did create an issue, and when I disassembled the transaxle case the synchros were hunky dory, and I know MTF-94 is a high grade formulation, and it’s easy for me to get; I have a great deal of confidence in the OEM fluid. If MTL is what you can obtain easily, then go for it, but there is nothing to fear from MTF-94.

 

I agree. I too use the "better" fluids in all of my motors. My reply was because you said you "thought" the old fluid broke down quickly. The manufactor tested it so unless you have tested OEM fluid then it would be a guess.

Redline MTL or Amsoil Sychromesh is the 2 products I would research for use. You could also try the Ford SVT focus forums since they use the same tranny.

 

k,

Are you referencing the stock fluid when you say MTF-94?

 

Yes he is.

I was hoping to get the exact kinematic viscosities. I know their weights in general, additives, etc...but we all know how it's very well possible to have a heavy 75 act like a light 80, and so forth (I know there's a firm dividing line, but the extra .1/.2 could be considered negligible). I'm curious as to whether the stock fluids, while exceptional in their additive's, and of a lower general viscosity than a comparable transmission fluid by an aftermarket vendor. I.E. is the cold viscosity of MTL, a 75W, higher or lower...and by how much...than the cold 75W viscosity value of OEM fluid...same question applies when warm. That was my primary goal in starting this thread. I will go off your analyst's recommendation in lieu of any firm viscosity numbers.

Was also wondering the same about the OEM motor oil, to see what viscosities (not weights) Mini seems to think is best...I have a general feeling that the 5W-30 they recommend is of a "heavier" sort but a blend instead of a full synthetic as well. More guesswork on my part, but that's why I started the thread.

- Matt

 

Here's what I have on cold & hot; MTF-94 viscosity after 14,921 miles.
(40C) 39.7 - 75W
(100C) 7.4 - low side of 80W

 

k,

what change intervals would you suggest for the oem fluid?

 

Think I finally found MTL and MT-90 viscosities as well...buried in a small-text linked PDF :

http://www.redlineoil.com/pdf/6.pdf

MTL (70W80)
@40oC: 56.2
@100oC: 10.6

MT-90 (75W90)
@40oC: 90.0
@100oC: 15.6

Definitely answers some questions there. Mini's stock fluid is damn light as far as a 75W80 goes. Lies about the bottom of the spectrum for both the cold as well as hot weights. In light of this and the few figures posted, it would seem Mini's fluid is a good call...I would imagine that going heavier would just add more weight to the shift feel, take longer to warm up, and make synchro engagement slower (choppier). Unless I've been misinformed/misread the effects that heavier transmission fluid would have on a transmission.

Now I need to dig up the OEM motor oil viscosity.

Thanks a bunch for the reference point, Keith.

-Matt

 

ScottinBend, I don’t have a recommendation for an interval other than around 50,000 miles. Maybe after another 100,000 miles of analysis I will know what is right for my operational environment and the Quaife.

No matter the viscosity of whatever engine oil you choose to run, there will be the problem of fuel dilution with the R53. Yes it is true a heavier weight will maintain its minimum viscosity longer, but it will hinder performance through fictional drag for most of the service life.