Redline D4 versus MTL in the TR6060

[Camarotobeornottobe]

Mine won't be stored in the winter, but it won't get driven much either. Mostly a warm weather car. But, I would still never run the MTL straight. Mixing it with 2 or 3 parts D4 to one part MTL is what I'm wondering about. Looking at the viscosity chart and considering what that will do at various temperatures, I can't imagine it an issue from a viscosity standpoint.

I guess this comes down to whether the MTL is truly just a thicker version of D4, i.e. they contain roughly the same additives and the MTL is not missing or adding anything that would be of detriment to the TR6060. Both are GL-4 rated . . .

[Camaro Dude]

FWIW, I'm running the Redline D4 in my 1LE's M6 tranny.

I noticed no difference in shifting qualities, or noise reduction for that matter from the oem fluid. If I'm going to stretch my imagination, 1st to 2nd shift is slightly crisper after a cold start.

Here is a question for the OP and other users as well. Do you find that your shifts are not as "crisp and buttery smooth" once the tranny oil gets super hot after a hard run? If that's the case, then a lil MTL added in the mix might be the ticket.

Obviously, the D4 takes into account those driving their rides in the cold.

[Camarotobeornottobe]

Originally Posted by Camaro Dude

FWIW, I'm running the Redline D4 in my 1LE's M6 tranny.

I noticed no difference in shifting qualities, or noise reduction for that matter from the oem fluid. If I'm going to stretch my imagination, 1st to 2nd shift is slightly crisper after a cold start.

Here is a question for the OP and other users as well. Do you find that your shifts are not as "crisp and buttery smooth" once the tranny oil gets super hot after a hard run? If that's the case, then a lil MTL added in the mix might be the ticket.

Obviously, the D4 takes into account those driving their rides in the cold.

Noise.

To explain, I'm actually thinking along the same fashion. My theory is that the ATF is "required" AS A GENERAL RULE because of cold shifting characteristics. However, the tranny might be in a less than ideal state when really hot.

Frankly, the tranny really shifts the same for me, cold or hot, whether with OEM or D4. I noticed a marginal noise reduction with D4 over the OEM, and the tranny continues to quiet as I break it in. I have about 800 miles on the car now.

One thing is clear to me though -- the tranny is louder when the fluid gets hot. Camaro owners might have to put all the windows up and turn the radio down to hear it, but I'm confident they all do it in varying degrees whether you consider it "normal" or not. As stated in another thread, part of me thinks it sounds cool. Camaro Dude, you described it as a chain rolling over sprockets when at low RPMs.

But, I'm confident the reason for increased noise is because the fluid thins out so much. Tremec is okay with it because some "normal" drivetrain noise is better than hard shifts while cold and the ATF does fine for keeping the tranny alive past warranty mileage/dates. You could also argue that they installed a fluid pump that can only handle the ATF and nothing substantially thicker.

A long winded way of beating this to death and again saying I think a mix of MTL, whether 1/4, 1/3, or 1/2, might be the ticket. Could it smooth out when hot while keeping the cold shift problems away if only mixed?

[Camaro Dude]

Originally Posted by Camarotobeornottobe

Noise.

To explain, I'm actually thinking along the same fashion. My theory is that the ATF is "required" AS A GENERAL RULE because of cold shifting characteristics. However, the tranny might be in a less than ideal state when really hot.

Frankly, the tranny really shifts the same for me, cold or hot, whether with OEM or D4. I noticed a marginal noise reduction with D4 over the OEM, and the tranny continues to quiet as I break it in. I have about 800 miles on the car now.

One thing is clear to me though -- the tranny is louder when the fluid gets hot. Camaro owners might have to put all the windows up and turn the radio down to hear it, but I'm confident they all do it in varying degrees whether you consider it "normal" or not. As stated in another thread, part of me thinks it sounds cool. Camaro Dude, you described it as a chain rolling over sprockets when at low RPMs.

But, I'm confident the reason for increased noise is because the fluid thins out so much. Tremec is okay with it because some "normal" drivetrain noise is better than hard shifts while cold and the ATF does fine for keeping the tranny alive past warranty mileage/dates. You could also argue that they installed a fluid pump that can only handle the ATF and nothing substantially thicker.

A long winded way of beating this to death and again saying I think a mix of MTL, whether 1/4, 1/3, or 1/2, might be the ticket. Could it smooth out when hot while keeping the cold shift problems away if only mixed?

I'm right with you on your hypotheses, and the only way forward to a conclusion here, is for some one to go first, and report back observations.

I already did this back in the day, when I lived on the bleeding edge, and tackled the (now infamous) BMW Getrag rattle on the 260 units, head on. I ditched the OEM stuff, even the O.E equivalent, Redline MTL, and I used the thicker MT-90. BINGO we had a winner No more rattle like marbles sound.

Soooooo, coming now to the present, and the Let's Mix a lil MTL, Into The D4, Experiment, who will go first?


NOTE* I think this is an important point to make. In both cases above, it should be noted that I NEVER drove the cars in the winter, meaning pretty much anything below freezing points. Having said that, I would not recommend the above oil types if the car is to be driven daily in the colder climates, where temps could drop to double negative figures.

[Camarotobeornottobe]

I'm still a little afraid to try, LOL. You're on deck as the obviously more seasoned scientist

Any input on the TR6060's "fluid pump?" Would asking it to pump slightly thicker fluid bother it? My theory would be no, since the pump works when the fluid is only 75% warmed up, so thicker fluid at 100% warmed up would be the same. When completely cold, the thicker fluid would be harder on the pump, but it wouldn't be in that condition for long.

[Camarotobeornottobe]

So, I wanted to report back for everyone's benefit.

My conclusion from research:

I concluded that mixing D4 and MTL 50/50 would be okay. I came to this conclusion based on communications with Redline, Tremec, forum members who had used MTL, Corvette TR6060 results, and a few speed shops (including JRE, which HIGHLY recommended going straight MTL). After all, we are only talking about raising the viscosity slightly when doing this mix, with the cold viscosity going from 34 to 44 cSt, and the hot going from 7.5 to about 9.0 cSt. The two are basically the same GL-4 synthetic fluids with one just being slightly thicker. Research also points to the manufacturers "requiring" the thinner ATF in order to minimize effort needed when the tranny is cold. Since my car will rarely be driven in the winter, it was less of an issue. Research also indicated that thickening the fluid would quiet down an otherwise noisy tranny.

Results:

I put it in when the weather was 85 degrees. My first reaction was WOW. The shifts seemed smoother and the tranny quieter. So much so, I almost regretted not going 100% MTL. But, I waited for some more thorough driving.

Now, I have been driving around about a week. At all temperature stages, the tranny is considerably quieter than at the same temperature with straight D4. By that I mean, it still gets louder when the fluid gets hot and thinner, but always quieter than the D4 was at the same temperature. To be clear, by "louder," I'm talking normal TR6060 gear noise, not a mechanical problem.

Importantly, when warm, shifting is noticeably smoother than with D4 alone (which was already an improvement over the OEM fluid). I am confident it is protecting the tranny better at these higher temperatures.

I purposely drove the car at cold start-up without letting it warm up. We have had a couple of 60 degree mornings, though my car was in a non-heated garage that stayed around 70. Shifting was slightly stiffer when cold, but only marginally so and only for the first couple of shifts. Obviously, the real test won't be until the dead of winter. However, while my car won't be officialy stored during the winter, it won't be driven much either. So, any downside to using some MTL should be mitigated.

Bottom line, I recommend doing the mix. Hope this helps others.

[White_SS/RS]

My thoughts on this is the OEM fluid seems thicker than D4. Of course I don't have the viscosity of the OEM fluid to be certain. Anyone have this info? So in my opinion I don't see a problem running straight MTL. Any problems with the pump would be seen as parasitic drag (more power to drive the pump). For racing use I'd go all MTL, don't see a problem in mixing for those in colder weather.

[USMUCL]

As I recall, the OEM is just slightly thinner than the D4.

Reference the MTL, it is probably worth noting it is thicker than OEM and D4 AT THE SAME TEMPERATURES. So, to claim MTL might hurt something (like the pump) would mean that the D4 would be just as harsh on it when the trans is slightly cooler.

[speedygonzales]

Others on the website are using this.

http://www.royalpurpleconsumer.com/p...mission-fluid/


Haven't decided what I will use but since I'm a amsoil guy will probably go with their ATF since I use it in my Z71.

[White_SS/RS]

Found the 40*C cSt viscosity for gm synchromesh to be 38 cSt. This puts the cold viscosity slightly higher than D4 which is 34 cSt. Anyone have or able to find synchromesh viscosity at 100*C.

My Sorce (section 9)~
https://www.servicechamp.com/images/104006msds.pdf

[Camarotobeornottobe]

From another site. Same person recommends that, if you are trying to go higher viscosity, you go MTL rather than Syncromesh. It is from 2003 though, so the characteristics might have been changed slightly (the MTL #s don't quite match perfectly to the #s given on Redline's site today):

http://www.svtperformance.com/forums...esh-v-Red-Line

Let's look at its chemical properties of GM Syncromesh:
cST 40degC: 41.6
cST 100degC: 9.08
Pour point: -50
Flash point: 385degF
Color: amber

Let's look at Red Line D4ATF (typical ATF formulation)
cST 40degC: 34.0
cST 100degC: 7.5
Pour point: -60
Flash point: 437degF
Color: Red

Let's look at Red Line MTL
cST 40degC: 50.8
cST 100degC: 10.2
Pour point: -50
Flash point: 450degF
Color: Red

Let's look at Amsoil ATF
cST 40degC: 36.0
cST 100degC: 7.5
Pour point: -69
Flash point: 432degF
Color: Red
************************************************

[White_SS/RS]

something more current for comparison purposes would be better. Synchromesh today seems a little thicker than D4 but it would be nice to know for sure where it sits for sure.

[Camarotobeornottobe]

Just to be sure -- you're NOT talking about what comes in our cars stock, nor are you talking about Pennzoil Syncromesh, right?

[wakespeak]

AC Delco makes 2 transmission products: synchromesh 88900333 and manual transmission and transfer case fluid 88861800. 88861800 is specified for the tr6060 not synchromesh.

I think for manual transmissions you have to consider 2 things : lubricating the metal parts and having the right friction characteristics for the synchronizers to work well and live a long time. Most atf products are "friction modified" to allow the clutches to engage properly. The tr6060 makes some assumptions like this for the synchronizers.

Redline probably adds friction modifiers to its products but I don't know how compatible those are with the materials Tremec is using for the synchronizers. It may work great, but wear out the synchronizers faster. The reason I am pointing that out is that even within the various atf's friction modifiers vary a lot. Don't go putting Dexron in a Chrysler transmission for instance. Whether the tr6060 is that sensitive to say d4 to a mix with mtl to gm stock fluid just not sure, but I have taken the middle in my mind with a synthetic atf.