RedLine MTL - BIG improvement!!!!

What I want to know is, if I can mix the 75w90 NS with the MTL.

 

Yes, I had checked with Redline, all their transaxle fluids can be blended. I have found the MT 90 to best for my car, the MTL did shift well but just a smidegen of notchiness compared with the MT90. The 75w90 ns was ok, but on the margin of having the second gear balkiness when near freezing cold before the gearbox warmed up. But these are all very subtle differences. Never had any lsd chatter, if one did, adding half a quart 75w90 non NS would be the blend.

 

One DOWN side re MTL in my 328

Although the shifting in all forward gears on my 328 is dramatically improved as I stated earlier, I have found that shifting into reverse is noticeably more difficult now. Previously, with the Motul, shifting into reverse wasn't a noticeable problem - I just shifted into reverse. With the MTL it will grind every time unless I shift into 1st gear and THEN into reverse. In that case, it goes easily into reverse. I have read that that grinding into reverse is fairly common and the "fix" is to shift into 1st first. but I had not experienced it with the Motul. That being said, even if I had to shift into reverse before starting the engine, I would happily do so for the improvement MTL made in the overall shifting.

 

+1 I experienced the same when switching from the NS. No biggie. Had to do the same on my Alfa even with a brand new tranny.

 

Weird. Mine had exactly this transformation (and same 1st->reverse cure) after going to MTL. I just thought it was my car being snarky. I haven't tried going "solo reverse" in a while to see if it still grinds w/out hitting 1st, first... so don't know if it clears up after awhile

 

I was wondering, with the 75w90 NS in my gearbox now, I can shift 1st to 2nd And reverse from start up (cold) SO, with your experience with the MTL, I’m assuming I will have the same experience when I switch to MTL, and this is why I’m wondering if I can mix the NS and the MTL and what would be the outcome.

 

Lots of threads back in the day (8-10 years ago) about mixing MTL and NS. 4 bottles of MTL and then the rest with NS. So a partial bottle of NS in with the MTL

 

Speaking of Redline.

 

I was impressed with the video because NOT ONCE did he recommend using Red line products. It is seldom you see such an objective presentation by a representative of a company that sells things!

Excellent info for anyone with some of the typical lube questions.

 

Very interesting. Thank you for posting.

- Confirms that GL-4 (MTL) is the right stuff.
- Interesting comments on leakage after conversion to synthetic engine oil.
- Interesting comments regarding Top Tier fuel.
- I guess I need to start watching oil temp.

 

Very informative video, who says your to old to learn
Just posted it across the pond on CS site for others to be educated

 

Re oil temp - on the gauge in my 328, the oil temp in normal driving stays around the 210 mark or slightly under that. ASSUMING the gauge is at least in the ballpark, that would indicate that the oil running at its spec weight. As he pointed out in the video, track use would probably likely that temp considerably, and a grade heavier would be better for that purpose.

However, that method (temp) is not what we used to decide on oil weight...

We always selected oil viscosity based on oil pressure at operating temp. I have to say that to me, looking at temp to decide viscosity is sort of "back-dooring" the question. If the oil pressure is sufficient throughout the rev range in the conditions appropriate (track, street, whatever), than the lowest weight that produces that pressure is correct; anything heavier is just wasting HP. Obviously, temp is important in the sense that if it goes high enough, any oil can break down but that level of heat is extremely unlikely, especially with synthetic oils. Also, cars are more likely to have an oil pressure gauge than an oil temperature gauge so it seems to me that checking pressure is easier as well. Since what you are worried about at all times is that there is sufficient oil pressure in the system to do the job, looking at the oil pressure in the situation is the direct "answer" to the question of whether the viscosity is sufficient for the application. To me temperature is an indirect way and might even produce an unnecessary change. If the pressure is OK with, say 40 wt at 240F, there's no reason to put 50 wt in.

I think I will send a message asking his views on the point, above. I would be interested to hear his view on why pressure was not considered. There could be something here that I need to learn!

 

The oil pressure gauge will not give you a good indication if you are using a to heavy oil, the oil pressure is regulated. But as he says in the video, the temp characteristics could.

 

I thinks beside oil pressure, volume is just as important in fact maybe more important than pressure.

 

Well, this probably doesn’t apply for the gearbox but does apply for the crankcase.

 

It's not really necessary to know anything about the volume. The manufacturer of the engine determines what the pressure should be to provide proper lubrication based on the system and the engine clearances. The "volume" of oil per second (or minute, whatever) it takes to do that is automatically "correct" if the pressure is within spec. Therefore, pressure is all you really need to know; if the pressure is satisfactory, the volume of oil is also satisfactory by definition. If the standard oil pump in good condition cannot supply sufficient pressure, the engine needs to be rebuilt because the clearances are excessive.

OTOH, competition engine often use a high volume oil pump because they frequently have large internal clearances compared to production cars. In those cases a high volume pump can supply sufficient pressure when an OEM pump may not be able to do so.

FWIW, the standard 10 PSI per 1000 RPM under load has been a standard for a LOOONG time and it is still pretty much the common application. The Red Line guy, however, made an excellent point that I had never thought about - the fact that many modern engines that use variable cam timing (He specifically mentioned BMW) need oil of a certain weight to operate that system properly. So, in that case, viscosity may be dictated by that system, not the "rest" of the engine. Interesting stuff.

 

Well, pressure X isn't the true goal. Proper rate of flow is the goal.

 

That can't be right. The pressure is regulated and the flow will depend on viscosity.

 

Yes, the volume of oil IS the goal but the pressure determines the flow (volume) based on the clearances in the engine and oil passages in the system. The engine manufacturer has (hopefully) determined the pressure needed to provide that volume and given a pressure spec for that - like Ferrari's 85 PSI at 6500 RPM. So you don't need to know what volume the Ferrari engine needs - Ferrari already figured that out and publishes a pressure spec to achieve it.

Yes the volume delivered DOES change with temperature and viscosity BUT, again, as per above, the manufacturer of the engine determines and publishes the spec that automatically ensures the volume is adequate if the pressure is adequate. IOW, any difference that actually occurs with flow (volume) based on temp/viscosity doesn't matter - it still falls within the range that provides adequate engine protection.

That's not to say there can't be a problem if, as noted earlier, oil that is too heavy is used. In that case,I suppose it IS possible that insufficient oil could be moved through the necessary areas even though pressure is OK. Seems to me that would require oil that was much heavier than what the manufacturer recommended but I guess it could happen, especially with a cold engine using straight-weight oil.

I got a nice response a few minutes ago from Red Line; I did not ask Dave if it was OK to post his response here so, to paraphrase, he suggests that temp and pressure are both important and that if oil pressure is too low, a higher viscosity oil can help. He points out that if higher viscosity oil is used it will also operate warmer and that many times the higher viscosity oil is a band aid for other issues. He restated his point in the video that if say, 40 wt is spec and you go with 30 because pressure was still OK, it "might not provide the protection expected.":

 

Mike996,

In your new role as our ad hoc ambassador with RedLine , would you be willing to ask another question?

I am curious about what RedLine says about oil change frequency for our cars. In the video, he alludes to the much higher stability of synthetic oils compared to conventional oils but only in the context of high stress applications (such as racing). Are they also more stable in the sense that they can sit unused in an oil pan for longer periods of time? Asked another way, how frequently should they be changed on a calendar basis?

As is typical of many of us, I only put about 2,000 miles on my car per year and yet change the engine oil annually. Like the "every 3,000 miles" rule the "at least once per year" rule may be antiquated.

Personally, I use synthetic (in my case Mobil1 0W40) and living in California, the oil probably doesn't get a whole lot of moisture in it over the year. The only issue would be evaporation of additives over the 12 month period.

I can ask this question myself but would hate to see the poor guy inundated with email. I am thinking it might be better if you ask.

 

It's ironic, I have never in my life used a Redline Product until I bought MTL (per RifleDriver) a week ago! But I'll see what I can do with my new friend Dave at Redline. I'll also ask if he's ok with me posting his response(s) as direct quotes.

 

Response from David is that even with modern synthetics, Including Redline products, the oil should be changed annually because the oil's additive package deteriorates over time and gets further used up holding contaminants in suspension. This is not related to engine operation (mileage) just time.

 

Thank you, Mr. Ambassador. A nice unambiguous answer.

 

Some say just replace the oil filter, before you knew it, the dirty old oil will be clean again as it will all be filtered again, hmm!

 

Just a FWIW note that probably everyone already knows as far as using GL4 (like Redline MTL): the data plate in the engine compartment (at least on my '89 328) specifically states to use GL5; the owners manual lists AGIP Rotra SX as appropriate which is also a GL 5. I'm sure the 5 is specified to ensure the differential does not chatter in a tight turn but I've not yet heard any chattering from my 328 since I changed to MTL.