[edycol]

Originally Posted by chris719

No, I understand perfectly how it works. My S54 engine came filled with Castrol TWS 10W-60. You could do a UOA and tell. BMW did not fill it with a secret Castrol product and sell TWS only to retail.

There is zero chance that BMW or Porsche has paid Pentosin to develop an exclusive lifetime fill DCT fluid that is NOT the same fluid that they sell to dealers which is also an exclusive lifetime fill DCT fluid. It would be the height of stupidity.

Assumption is mother of all screwups!
Only thing you can say is: there is zero chance.

S54 was a niche product and 10W60 was a band aid. It was a uniqe issue.
Every component requires its own solution.
You can believe whatever you want, but your first fill in DCT will be Group III product that is compromise between limited oxidation and performance.

Aftermarket products, INCLUDING Pentosin that is sold as. PENTOSIN is different story.
You are constantly comparing apples and oranges.
Now, whether Refline is better than Motul that is better than Pentosin, or other way around, is in the eye of beholder.

[chris719]

Originally Posted by edycol

Assumption is mother of all screwups!
Only thing you can say is: there is zero chance.

S54 was a niche product and 10W60 was a band aid. It was a uniqe issue.
Every component requires its own solution.
You can believe whatever you want, but your first fill in DCT will be Group III product that is compromise between limited oxidation and performance.

Aftermarket products, INCLUDING Pentosin that is sold as. PENTOSIN is different story.
You are constantly comparing apples and oranges.
Now, whether Refline is better than Motul that is better than Pentosin, or other way around, is in the eye of beholder.

We'll agree to disagree.

I just clicked a Walmart listing for Pentosin FFL-4:

Offers lifetime performance

The only one speculating here is you, who are speculating that Pentosin can't meet lifetime fill specs with any amount of Group IV. The problem is, you have no idea if that's actually true because you aren't a chemical engineer that works for Pentosin. If the fluid couldn't be safely used for lifetime fill, the dealers would have to be told this. Instead, the retail bottle says it is a lifetime fill. Say whatever you want, I would bet all my money that the factory fill and retail product is the same for these DCT fluids.

[edycol]

Originally Posted by chris719

We'll agree to disagree.

I just clicked a Walmart listing for Pentosin FFL-4:

Offers lifetime performance

The only one speculating here is you, who are speculating that Pentosin can't meet lifetime fill specs with any amount of Group IV. The problem is, you have no idea if that's actually true because you aren't a chemical engineer that works for Pentosin. If the fluid couldn't be safely used for lifetime fill, the dealers would have to be told this. Instead, the retail bottle says it is a lifetime fill. Say whatever you want, I would bet all my money that the factory fill and retail product is the same for these DCT fluids.

What is lifetime?
Only people who know what is lifetime fluid are:
1. Engineers in BMW (and accountants).
2. People who determined exactly what mileage is lifetime.

To offer lifetime fluid that might be majority GrIV, is good marketing.
But it is nit lifetime. Liqui Moly also claims that German cars require German oil, but no German manufacturer uses their products. But they can vlaim whatever they want.

Also, BMW fluid is really not lifetime, bcs. ZF would strongly disagree with it, and they do.

[chris719]

Originally Posted by edycol

What is lifetime?
Only people who know what is lifetime fluid are:
1. Engineers in BMW (and accountants).
2. People who determined exactly what mileage is lifetime.

To offer lifetime fluid that might be majority GrIV, is good marketing.
But it is nit lifetime. Liqui Moly also claims that German cars require German oil, but no German manufacturer uses their products. But they can vlaim whatever they want.

Also, BMW fluid is really not lifetime, bcs. ZF would strongly disagree with it, and they do.

Fair, and I think we all know lifetime isn't what a customer would consider lifetime, but just a couple points.

First, the SDS is vague on the exact amount of Group IV. It could be as low as 25% based on how it's written. Second, all M-DCT and PDK from ZF are "lifetime fill". It is quite hard to believe that ZF disagrees too much with this since both Porsche and BMW agree. I'm sure ZF, as the vendor, communicates the MTBF and it met both of their targets. Especially if Porsche is signing on to lifetime fill, I would feel pretty good about that.

Porsche claims PDK is lifetime fill for most of their cars except the GT3 which the manual shows 96k miles or 12 years. It also shows 60k for some generations. I'd guess it's a pretty good fluid if Porsche will let you go 60k+ miles in a GT3.

[edycol]

Originally Posted by chris719

Fair, and I think we all know lifetime isn't what a customer would consider lifetime, but just a couple points.

First, the SDS is vague on the exact amount of Group IV. It could be as low as 25% based on how it's written. Second, all M-DCT and PDK from ZF are "lifetime fill". It is quite hard to believe that ZF disagrees too much with this since both Porsche and BMW agree. I'm sure ZF, as the vendor, communicates the MTBF and it met both of their targets. Especially if Porsche is signing on to lifetime fill, I would feel pretty good about that.

Porsche claims PDK is lifetime fill for most of their cars except the GT3 which the manual shows 96k miles or 12 years. It also shows 60k for some generations. I'd guess it's a pretty good fluid if Porsche will let you go 60k+ miles in a GT3.

PDK is made by ZF. Porsche also claims lifetime for ZF8 they use. Same as BMW does.
But, ZF has different opinion:
https://aftermarket.zf.com/sea/en/af...on-oil-change/

Now, if both are true, then either BMW and Porsche use unique fluid or ZF knows something that BMW and Porsche don’t know?

Or, third option, “lifetime” means warranty and potentially CPO warranty.

[chris719]

Originally Posted by edycol

PDK is made by ZF. Porsche also claims lifetime for ZF8 they use. Same as BMW does.
But, ZF has different opinion:
https://aftermarket.zf.com/sea/en/af...on-oil-change/

Now, if both are true, then either BMW and Porsche use unique fluid or ZF knows something that BMW and Porsche don’t know?

Or, third option, “lifetime” means warranty and potentially CPO warranty.

Sure, it's never infinite. That page is fairly generic though and surely doesn't apply to every type or model of transmission.

I found a screenshot from a manual and Porsche recommends 96k miles for that PDK fluid in a GT3. That is a car designed for a hard life, to say the least, and Porsche does not usually BS you on GT cars. I would change it sooner but it must be robust.

[edycol]

Originally Posted by chris719

Sure, it's never infinite. That page is fairly generic though and surely doesn't apply to every type or model of transmission.

I found a screenshot from a manual and Porsche recommends 96k miles for that PDK fluid in a GT3. That is a car designed for a hard life, to say the least, and Porsche does not usually BS you on GT cars. I would change it sooner but it must be robust.

No one here claimed Pentosin is not robust. They make best steering fluid, they supply brake fluid to half a Euro manufacturers.
But, I personally wouldn’t say that is most robust product from performance aspect. On the street, it doesn’t really matter.

[chris719]

Originally Posted by chris719

I did come across the Motul High Torque DCTF, but I am not sure if this is appropriate for the 6MT. The datasheet doesn't show any MT applications unlike the Multi DCTF. It does reference FFL-3 but not MTF-LT-5. I reached out to Motul to get their thoughts and will let you know what they say.

Motul’s technical support manager got back to me and said that:

The fact that we did not list some of the manual transmission specifications we could have for the High Torque DCTF is related with product segmentation and with a future non-friction-modified fluid we will have available in the near future.

While we wrap-up the launch of that product, you can use High Torque DCTF in applications calling for SAE 75W API GL-4 profiles, such as the BMW MTF-LT-5 spec you mentioned in your email.

So, looks like that’s a good option if someone wants a fluid at around 6.5 cSt vs 8 of the Red Line.

[David.m]

I now use Redline DCTF & won't go back to oem.

I bought car new and from early in it's life had an intermittent issue of selecting 1st when stationary (eg waiting at a red light in neutral, solution was either select 2nd then back to 1st or release/re-engage clutch). 20yrs ago this wouldn't have been a big issue but these days impatient people behind hit their horn probably thinking I'm on my phone rather than focussed on driving! No other shifting issues & I've had other manual cars with a similar intermittent issue selecting 1st so never bothered seeking a warranty fix.

At 66K km I changed oil with the oem MTF-LT-5, shifting was noticeably smoother but the intermittent issue selecting 1st persisted.
At 85K km (while doing CDV delete) I changed trans oil again, this time to Redline DCTF as there was no stock of the oem in Australia (& wouldn't be for 2+months said BMW AU). I can't say I noticed any real change to shifting, after all the oem oil was only 20K km old, but the selecting 1st issue ceased completely, literally has not occurred again.
At 109K km I changed again using Redline DCTF, no change to shifting and selecting 1st has again never been a problem, currently at 112K km.

[DriftKr6l]

Originally Posted by David.m

I now use Redline DCTF & won't go back to oem.

I bought car new and from early in it's life had an intermittent issue of selecting 1st when stationary (eg waiting at a red light in neutral, solution was either select 2nd then back to 1st or release/re-engage clutch). 20yrs ago this wouldn't have been a big issue but these days impatient people behind hit their horn probably thinking I'm on my phone rather than focussed on driving! No other shifting issues & I've had other manual cars with a similar intermittent issue selecting 1st so never bothered seeking a warranty fix.

At 66K km I changed oil with the oem MTF-LT-5, shifting was noticeably smoother but the intermittent issue selecting 1st persisted.
At 85K km (while doing CDV delete) I changed trans oil again, this time to Redline DCTF as there was no stock of the oem in Australia (& wouldn't be for 2+months said BMW AU). I can't say I noticed any real change to shifting, after all the oem oil was only 20K km old, but the selecting 1st issue ceased completely, literally has not occurred again.
At 109K km I changed again using Redline DCTF, no change to shifting and selecting 1st has again never been a problem, currently at 112K km.

Good info👍

[edycol]

Originally Posted by chris719

Motul’s technical support manager got back to me and said that:

The fact that we did not list some of the manual transmission specifications we could have for the High Torque DCTF is related with product segmentation and with a future non-friction-modified fluid we will have available in the near future.

While we wrap-up the launch of that product, you can use High Torque DCTF in applications calling for SAE 75W API GL-4 profiles, such as the BMW MTF-LT-5 spec you mentioned in your email.

So, looks like that’s a good option if someone wants a fluid at around 6.5 cSt vs 8 of the Red Line.

That is OK, but more important is how fluid holds.
Higher CST means potentially more shearing. I say potentially as that depends on base stocks and VII.

[n8dgr84]

Originally Posted by David.m

I now use Redline DCTF & won't go back to oem.

I bought car new and from early in it's life had an intermittent issue of selecting 1st when stationary (eg waiting at a red light in neutral, solution was either select 2nd then back to 1st or release/re-engage clutch). 20yrs ago this wouldn't have been a big issue but these days impatient people behind hit their horn probably thinking I'm on my phone rather than focussed on driving! No other shifting issues & I've had other manual cars with a similar intermittent issue selecting 1st so never bothered seeking a warranty fix.

At 66K km I changed oil with the oem MTF-LT-5, shifting was noticeably smoother but the intermittent issue selecting 1st persisted.
At 85K km (while doing CDV delete) I changed trans oil again, this time to Redline DCTF as there was no stock of the oem in Australia (& wouldn't be for 2+months said BMW AU). I can't say I noticed any real change to shifting, after all the oem oil was only 20K km old, but the selecting 1st issue ceased completely, literally has not occurred again.
At 109K km I changed again using Redline DCTF, no change to shifting and selecting 1st has again never been a problem, currently at 112K km.

I've had this same issue and when I let the clutch out to just before the engagement point, the shifter "slips" into gear.
Have you ever experienced that?
What are the odds that the CDV delete is a factor? Seems unlikely, I suppose, since it's a mechanical engagement.
Nice to know that some fluid could help solve this completely!

[David.m]

Originally Posted by n8dgr84

I've had this same issue and when I let the clutch out to just before the engagement point, the shifter "slips" into gear.
Have you ever experienced that?
What are the odds that the CDV delete is a factor? Seems unlikely, I suppose, since it's a mechanical engagement.
Nice to know that some fluid could help solve this completely!

Never tried easing the clutch out to see if it would 'slip' into gear (assume you mean maintaining pressure against the 1st gear gate when releasing the clutch?) I wouldn't do it personally, I'm either in neutral or fully into a gear before I release the clutch.

I'm sure the CDV delete has no influence, it's likely an issue with the 1st gear synchro. I did read a comment on the forum very recently that someone thought their habit of not downshifting through to 2nd when coming to a stop then affected selecting 1st. It's a habit I've had forever for normal commute driving ie approaching red light etc I'll just go into neutral from whatever gear, release clutch and coast to a stop. I never considered that practise may contribute to the 1st gear issue, could be why it was intermittent (dependent on which gear I went to neutral from).

Any case I'm happy the Redline fluid has fixed the issue, downshifting to 2nd every time I'm coming to a stop in normal traffic doesn't interest me, I save that for the fun/spirited drives

[n8dgr84]

Originally Posted by David.m

Never tried easing the clutch out to see if it would 'slip' into gear (assume you mean maintaining pressure against the 1st gear gate when releasing the clutch?) I wouldn't do it personally, I'm either in neutral or fully into a gear before I release the clutch.

I'm sure the CDV delete has no influence, it's likely an issue with the 1st gear synchro. I did read a comment on the forum very recently that someone thought their habit of not downshifting through to 2nd when coming to a stop then affected selecting 1st. It's a habit I've had forever for normal commute driving ie approaching red light etc I'll just go into neutral from whatever gear, release clutch and coast to a stop. I never considered that practise may contribute to the 1st gear issue, could be why it was intermittent (dependent on which gear I went to neutral from).

Any case I'm happy the Redline fluid has fixed the issue, downshifting to 2nd every time I'm coming to a stop in normal traffic doesn't interest me, I save that for the fun/spirited drives

I don't put any pressure to "force" the shifter into gear while letting clutch out from being "half-cocked" - it seems to just slip in by itself (that's what she said)

[David.m]

Originally Posted by n8dgr84

I don't put any pressure to "force" the shifter into gear while letting clutch out from being "half-cocked" - it seems to just slip in by itself (that's what she said)

Force maybe the wrong word, but if it's not in gear and you let go of the shift knob it will return to neutral between 3-4 gears...maybe you're saying it's half way into 1st & then releasing the clutch fully engages when the teeth mesh

[n8dgr84]

Originally Posted by David.m

Force maybe the wrong word, but if it's not in gear and you let go of the shift knob it will return to neutral between 3-4 gears...maybe you're saying it's half way into 1st & then releasing the clutch fully engages when the teeth mesh

Correct - it is partially engaged into 1st and the synchro pulls it into gear with the engagement of the clutch.

[chris719]

Originally Posted by n8dgr84

Correct - it is partially engaged into 1st and the synchro pulls it into gear with the engagement of the clutch.

Hmm, that doesn't sound great. My Z4M did something like that with second but it would spit it out instead. I'm not saying it's a defective transmission but I don't like it at all. With first it's probably more forgivable since most MTs are a bit fickle going into first occasionally. It's never happened to me FWIW but I have under 10k miles.

[F87source]

I also wanted to update that I'm going to be getting redline dctf this summer (found a vendor near me selling it at $27 CAD a quart, quite good compared to the US pricing at $24USD a quart and it's cheaper than the bmw stuff which was like $35 a liter). So I'll be able to report back about how the redline dctf feels vs. new stock fluid. I hope it offers better feel, and longer life. But idk.

[hlm2c]

Originally Posted by F87source

I also wanted to update that I'm going to be getting redline dctf this summer (found a vendor near me selling it at $27 CAD a quart, quite good compared to the US pricing at $24USD a quart and it's cheaper than the bmw stuff which was like $35 a liter). So I'll be able to report back about how the redline dctf feels vs. new stock fluid. I hope it offers better feel, and longer life. But idk.

Looking forward to hearing your feedback on it. Thanks for volunteering to being a second guinea pig for us . Your reviews hold a lot of weight and are much appreciated.

[chris719]

Originally Posted by F87source

I also wanted to update that I'm going to be getting redline dctf this summer (found a vendor near me selling it at $27 CAD a quart, quite good compared to the US pricing at $24USD a quart and it's cheaper than the bmw stuff which was like $35 a liter). So I'll be able to report back about how the redline dctf feels vs. new stock fluid. I hope it offers better feel, and longer life. But idk.

I'm probably going to try the Motul High Torque DCTF. The reason being that the Redline is thicker, if only a bit, than OEM fluid, and I've never seen an instance where a thicker fluid improved synchro behavior. Doesn't mean it can't happen, though.

[F87source]

Originally Posted by chris719

I'm probably going to try the Motul High Torque DCTF. The reason being that the Redline is thicker, if only a bit, than OEM fluid, and I've never seen an instance where a thicker fluid improved synchro behavior. Doesn't mean it can't happen, though.

Ok sounds good! It'll be good to have more usage experiences.

My take on fluid swapping is to try and improve longevity, because in my experience the OEM fluid seems to deteriorate too quickly. In terms of improvements towards synchro behavior alot of m2 guys have said it's improved their shifting into first gear and any knotchiness which is already a good sign.


I'll know if it's any good if my 1-2 shifts stay smooth (mine just felt like it was resisting me slightly, no grinding or any weird popping out of gears) and the knotchiness stays away.

[edycol]

Originally Posted by chris719

I'm probably going to try the Motul High Torque DCTF. The reason being that the Redline is thicker, if only a bit, than OEM fluid, and I've never seen an instance where a thicker fluid improved synchro behavior. Doesn't mean it can't happen, though.

It depends on additives and how they react with base stocks.
I would not put too much attention on thickness as on chemistry when it comes to improvement.