The Great Oil Debate

[keoni1984]

I'm doing the MTG swap as well once I get back from my vacation. Figured I should go ahead and give her the fully synthetic fluid while I'm down there putting in my MGW shifter! I can't wait! This is the first time in my life I've been anxious to go home while on vacay... Love this car! BTW, I've had zero issues with my trans (08/10 build date) with nearly 18k miles on her, but I live in a warm climate...

 

[Rob72]

but I live in a warm climate...

That seems to make all the difference.

 

[JAJ]

The more I drive with MTF-LT2, the more I like it.

Just sayin'

 

[UnleashedBeast]

The more I drive with MTF-LT2, the more I like it.

Just sayin'

Get me some specs on the stuff to evaluate it.

 

[Napoleon85]

The more I drive with MTF-LT2, the more I like it.

Just sayin'

Get me some specs on the stuff to evaluate it.

Fun story ... I started Googling this stuff to see what it was and apparently its BMW OEM MT fluid. I found this thread of E46 owners (which has a Getrag manual trans) talking about how the MTF-LT3 (which there is some debate about on that site) resolved notchiness and rough shifts. Glad to head we aren't the only ones

http://m3forum.net/m3forum/showthread.php?t=281784 (fun starts on page 2 about half way down)

 

[Grabber2012]

Interesting none the less. I wonder how there getrag compares to ours?

 

[Grimace427]

Interesting none the less. I wonder how there getrag compares to ours?

I have a few coworkers who are BMW enthusiasts. I've heard them having issues with WOT 1-2 shifts because of soft motor mounts, mostly M3 owners but also 335i owners. Neither of my coworkers are techs and were not knowledgable about fluids, however.

 

[techcargt]

Fun story ... I started Googling this stuff to see what it was and apparently its BMW OEM MT fluid. I found this thread of E46 owners (which has a Getrag manual trans) talking about how the MTF-LT3 (which there is some debate about on that site) resolved notchiness and rough shifts. Glad to head we aren't the only ones

http://m3forum.net/m3forum/showthread.php?t=281784 (fun starts on page 2 about half way down)

On one of the forums they were trading it out for , wait for it ,,,,,,, Amsoil 75w-90 MTG to get them to shift better .

 

[JAJ]

I'm using the Pentosin version - http://www.crpindustries.com/pentosin/pressreleases/CRP-116_Pento_MTF2_2.pdf

I didn't expect it to work as well as it is, frankly. I've been driving manual transmission BMW's (V8 M5 and V8 M3) for ten years and none of the gearboxes (all came with MTF-LT2) ever shifted well when they were cold. I was actually planning to switch to something else when I saw the Pentosin at my local auto parts store, so I thought "I might as well give it a shot", and bought three liters and swapped it in (now that I've figured out how, it takes about 45 minutes including the time to get the car on and off the lift). Imagine my surprise when the shifting cleaned right up and the noise stopped. I still only have 300 miles or so on it, so its entirely possible that it'll turn to crap after some extended use, but for now, it's working really well.

As for other BMW gear oils, MTF-LT1 is obsolete and MTF-LT3 is even thinner than the LT2 and is not, according to BMW, interchangeable with LT2. BMW Motorsport (the race car division) offers modified factory transmissions for endurance racing (like Ford Racing does) and they call for MTF-LT2 as the service fill for those.

While there's been a lot said about viscosity and base oil selection, my belief is that an equally important parameter in getting a gear oil to work properly is the friction modifier package that the blender uses. The gear oil has to leave enough friction on the table that the synchro's can stop the rotating mass of the input shaft and clutch. If the oil is "too slippery" they don't stop turning quickly enough and you get a rough shift. Redline's website has a good article on it about this.

 

[UnleashedBeast]

^That's why formulators like Amsoil only use the correct amount of friction modifiers.

Example, friction modifiers in the wet clutch system of a motorcycle would destroy the clutch. Amsoil motorcycle lubricants do not contain any friction modifiers.

 

[JAJ]

^That's why formulators like Amsoil only use the correct amount of friction modifiers...

I believe the shape and material composition of the synchro rings and cones (brass, carbon, angles, number of ridges, etc) all play into determining just how much the "right amount" of friction modifier is for a given transmission. The only engineering team that actually knows the exact requirements is the OEM, or someone that the OEM has licensed. In the case of BMW and MTF-LT2, it seems that Pentosin has been granted the right to make fluids to BMW specs and sell them over the counter. However, just because their MTF2 works in BMW Getrag transmissions isn't sufficient reason to believe it would be even close to right for the Ford MT-82. That it seems to be working for me is just good luck, as far as I'm concerned.

That said, if the OEM fluid isn't working very well, then you end up doing what I'm doing: trying one after another until I find one that works.

 

[devildog1679]

WI here, I see temps as low as -10, but mid 20's are the average. My car is notchy for the first 5 minutes. Once it's warm it's smooth. In the first 5 minutes I double clutch the 2-3 shift. Same as the 1-2 shift but I normally start in 2nd.

 

[JAJ]

WI here, I see temps as low as -10, but mid 20's are the average. My car is notchy for the first 5 minutes. Once it's warm it's smooth. In the first 5 minutes I double clutch the 2-3 shift. Same as the 1-2 shift but I normally start in 2nd.

I think "notchy" at any temperature is the same as "not working right" so I'm looking for fluid that's never "notchy".

 

[atistang]

WI here, I see temps as low as -10, but mid 20's are the average. My car is notchy for the first 5 minutes. Once it's warm it's smooth. In the first 5 minutes I double clutch the 2-3 shift. Same as the 1-2 shift but I normally start in 2nd.

Wht not just go 1-3, thats how i roll lol

 

[ZXMustang]

I think "notchy" at any temperature is the same as "not working right" so I'm looking for fluid that's never "notchy".

I agree with the first part of your statement, but you will not find a fluid that will not be notchy in the cold atleast and offer the correct viscosity when the trans is up to temp. If you cant live with the cold notchyness, then you will have to live with a whining trans. No manual trans, with the correct viscosity fluid in it will be butter smooth in cold weather until its up to operating temp PERIOD. There is no magic fluid that will do this. And I hope you understand that if you put a lighter weight fluid in that will shift smooth cold, then you will be compromising the full operating temp performance of the trans with fluid that is too thin. Thats where the extra noise and damage will start. This is really not rocket science. Just baby the car for like 10 minutes max, and it will be ready to rock after that. Not to mention, you will always have the notch feeling between gears when you are driving around normal. That is normal operation. You should not be able to shift super fast when you are just putting around town. Thats not how the trans works.

 

[Wingspan]

All this rough shifting when cold stuff reminds me of the last new Mustang I purchased, a '96 GT. Every morning in the winter it would grind...not shift rough...GRIND if I tried to shift hard into second before it had warmed up. After a few miles it was butter, so I just learned to take it easy for a few miles and the car never gave me a minute of trouble in 5 years and ~75,000 of ownership.

I can't fully endorse the "all manuals do that" because I have owned a few other manual transmission vehicles that didn't shift noticeably different based on temp like my '96 and '12 Mustangs do but I don't think this trait is quite the end of the world either.

FWIW, I've got MTL in my car now. It shifts smoother than the stock fluid but it did not "fix" any of the cold morning stuff or left turn "nibble".

 

[ZXMustang]

All this rough shifting when cold stuff reminds me of the last new Mustang I purchased, a '96 GT. Every morning in the winter it would grind...not shift rough...GRIND if I tried to shift hard into second before it had warmed up. After a few miles it was butter, so I just learned to take it easy for a few miles and the car never gave me a minute of trouble in 5 years and ~75,000 of ownership.

I can't fully endorse the "all manuals do that" because I have owned a few other manual transmission vehicles that didn't shift noticeably different based on temp like my '96 and '12 Mustangs do but I don't think this trait is quite the end of the world either.

FWIW, I've got MTL in my car now. It shifts smoother than the stock fluid but it did not "fix" any of the cold morning stuff or left turn "nibble".

I have had several normal cars (DDs) that did this. And I have also owned an 04GT, 04 cobra, 07 C6 vette, 09 GT500 and now the 11GT and they all Did this. Not to mention all those previous cars mentioned had the Tremecs in some form, and they all had other quirks and shifting issues. The cobra was the worst. That car was almost impossible to speed shift. But the point is that this is not the first car, and wont be the last car with a manual that has quirks and cold shifting issues. My C6 was even worse that the 5.0 for cold weather shifting. That car had the 6060 like the GT500, and they are all plagued with issues too. Worse issues than our cars...... There are threads over at team shelby and SVTP with hundreds of replies about the 11+ GT500 1-2 speed shift lockout going on. Now thats a real issue.

 

[Grabber2012]

I have had several normal cars (DDs) that did this. And I have also owned an 04GT, 04 cobra, 07 C6 vette, 09 GT500 and now the 11GT and they all Did this. Not to mention all those previous cars mentioned had the Tremecs in some form, and they all had other quirks and shifting issues. The cobra was the worst. That car was almost impossible to speed shift. But the point is that this is not the first car, and wont be the last car with a manual that has quirks and cold shifting issues. My C6 was even worse that the 5.0 for cold weather shifting. That car had the 6060 like the GT500, and they are all plagued with issues too. Worse issues than our cars...... There are threads over at team shelby and SVTP with hundreds of replies about the 11+ GT500 1-2 speed shift lockout going on. Now thats a real issue.

The 6060 is a strong tranny and they should've put it in the 5.0s just for strength alone but there has been problems with it since they put it in the 07 gt500s.

 

[UnleashedBeast]

The 6060 is a strong tranny and they should've put it in the 5.0s just for strength alone but there has been problems with it since they put it in the 07 gt500s.

The T6060 problems were not really S197 specific. GM owners using the T6060 has also reported similar 1-2 shift issues at high rpm.

My T6060 was very notchy in cold weather, and seemed to take forever to smooth out when warmed up. The cold 1-2 shift always had a crunching feeling and you could tell it wasn't working well. To solve this issue, I used a true synthetic ATF. Now I'm able to shift the car in near freezing temps without the big 1-2 crunch, and the fluid warms/smooths out much faster. The factory Mercon V fill in the T6060 sucked.

Amsoil ATF

 

[JAJ]

I agree with the first part of your statement, but you will not find a fluid that will not be notchy in the cold atleast and offer the correct viscosity when the trans is up to temp. If you cant live with the cold notchyness, then you will have to live with a whining trans. No manual trans, with the correct viscosity fluid in it will be butter smooth in cold weather until its up to operating temp PERIOD. There is no magic fluid that will do this. And I hope you understand that if you put a lighter weight fluid in that will shift smooth cold, then you will be compromising the full operating temp performance of the trans with fluid that is too thin. Thats where the extra noise and damage will start. This is really not rocket science. Just baby the car for like 10 minutes max, and it will be ready to rock after that. Not to mention, you will always have the notch feeling between gears when you are driving around normal. That is normal operation. You should not be able to shift super fast when you are just putting around town. Thats not how the trans works.

I know you're right, but I'm going to look for one anyway. I'll cycle through a bunch and see which ones do what. Some will be better cold, some will be better hot, some will be good but not great at all temperatures. I'm going to settle for one or maybe two (summer/winter) that work best for my needs. While I'm not a mechanical engineer, I learned to drive a standard transmission over 40 years ago, and along the way I've driven lots, including one summer job driving a dump truck with a non-synchronized gearbox. I've also rebuilt four or five manual gearboxes over the years, so I have a feel for what's going on inside the box from the sensations in the gear shift lever.

One thing that the NHTSA investigation did was to put a bunch of the OEM information that we normally wouldn't see into the public domain. For instance, the specified lube for the MT-82 was the Dual Clutch fluid. Ford only switched to the thicker 75w-90 fluid at the last minute as a "bandaid" for the noise problem. Ford put in writing to the NHTSA that the MT-82 transmission will deliver its full service life with either of the two oils in it, so it's probably true.

Knowing that, my search for the perfect gear oil amounts to finding a fluid with a V100 viscosity over 6.6 cSt and less than 15.6 cSt with a friction package that shifts nice.