I just filled 3 quarts of Redline Racing ATF in my 3G TL as recommended by some knowledgeable members of the 3G forum (thank you I Hate Cars and Inaccurate for the research on this). I plan to do a 1x3 on my 4G as well today.

I will be draining 3 quarts of the DW-1 ATF and filling back 1 quart of Redline Lightweight Racing ATF and 2 quarts of Redline Racing ATF. I will report back on the results.

Based on my experience with the 3G, after filling with Racing ATF, the tranny shifts slightly quicker, there is no longer any "popping" that used to occur between 2nd and 3rd gear, and shifting is slightly smoother (possibly because it is also slightly quicker).

Here's the thread from the 3G forum: https://acurazine.com/forums/perform...ng-atf-764322/

 

What millage are you at on your 4G and 3G?

How soon does the ATF need to be changed?

I just picked up a 2012 with 15k miles and I am wondering if I can squeeze a bit more performance out of the AT with better fluid.

 

My 3G is at 96k miles and my 4G is at 72k. I plan to do an ATF flush i.e. 3x3 every 20k or roughly every 3rd oil change.

More so than anything, I went with Racing ATF because of the reduction in clutch wear. The theory is that if there are less friction modifiers in the ATF, then the clutches will slip less and that would mean less friction and clutch wear. The other benefit of this being quicker shifts.
Racing ATF has ZERO friction modifiers so basically I am reducing the FMs in my tranny by about 1/3rd.

Anyways, something came up yesterday and I wasn't able to add the racing ATF. I will have to do it on Monday at the earliest.

 

RedLine makes great product! I typically use RedLine, Royal Purple, or Amsoil.

 

I view all of this sort of discussion with scepticism. Nothing personal, no offence.
Do you guys know how an automatic actually works?
Have you ever seen one taken apart and all the pieces laid out on the bench?
E.g. do you know that when the transmission shifts, it goes from locking up one gear set to locking up another? When you are in, say, second gear, the other gears are essentially in neutral.
When you shift from second to third, the gear for third has to lock up.
The engineers set this up so that there is a very slight overlap before second gear is "released". That's why you feel a slight difference in the power transmission, the trans is essentially in two gears at once for a very split second. The alternative would be to release (in this case) second gear a bit before third is engaged. This would put the trans in neutral for a very short time instead, but you would have a slight flare up of engine revs. The shifting "mechanism" is all controlled by switches or valves (same thing) that are controlled by the powertrain computer. The ATF has very little bearing (not a pun!) on how the trans shifts except in a very indirect way over time. If a trans is in good shape, working properly, I would be hard pressed to believe that anyone could detect any differences in shift quality when going from one quality oil to another. It is generally not "friction" that causes clutches to wear, it's heat caused by abuse. The heat deteriorates the adhesive that holds the clutch friction material on the steel plates. The best thing you can do for your auto trans is get an ATF cooler and don't abuse it.

 

Honda's Z-1 fluid used a LOT of friction modifiers that help smooth out shifts but that would lead to heat related failures. This came up on the 2G TL and 3G TL to a lesser extent. Folks have swapped fluid and reported a vast difference in shifting quality. After all the fluid is what holds the power in the torque converter!

 

Same scepticism here. Long time ago I have learned my lesson with a 98 v6 accord auto tranny not to mess with the tranny oil from other brands... very costly lesson too.

BTW, tranny oil is flammable when hot so careful what you all doing.

 

I drained and filled my stock ATF with 4 qts Royal Purple Max ATF after 31k miles yesterday. I am noticing an improvement in shift speed.

 

I am not trying to be argumentative!


After all the fluid is what holds the power in the torque converter!


This is a non-sequitur in this discussion. The torque converter transmits power (torque) to the transmission from the engine. Any old fluid will perform the torqueing function between the impeller and the turbine. (But it might not be compatible with he lockup clutches in the TC!) Yikes.

The TC is not involved in shifting gears per se. The TC is actually external to the transmission. The shifting of gears occurs inside the transmission as clutches engage and disengage. The fluid has to be compatible with the clutch materials. Unless you know that Brand X fluid has been tested and approved for Acura transmissions you are taking some risk by using it. But go ahead, it's your car! And good luck!

 

jim_c I understand your skepticism. I was just like you before I changed the ATF on my 3G. But as I said before, the improvement in shifts on my 3G is really noticeable! And keep in mind that I went straight from brand new DW1 in my tranny to a mixture of DW1 and 35% racing fluid. I didn't have any of the old garbage Z1.

As far as transmission shifts go, you almost got it spot on in your explanation. Except, since the 3G TL, acura has programmed the ECU to cut throttle on gear shifts (again for a split second). This eliminates flares and wear on the clutches.

The benefit of racing ATF that has no FMs is related to how the clutches engage. Less FMs mean the clutches grab quicker, spin less until they reach static friction, and as a result generate a lot less heat in the process. The friction material lasts longer and the tranny runs cooler. This topic has been discussed to great extend in the 3G thread I linked above. Take a look if you're interested. There are some really knowledgeable people who contributed to this discussion.

Anyways, now to the fun part. I was able to do a 3x1 yesterday and fill up with 1 quart lightweight racing ATF and 2 quarts racing ATF. I have only driven the car 15-20 miles since the fill and am happy to report that shifts are a little bit quicker and decisive. There is no flaring at all. The improvement in shifts does not feel as drastic as the improvement I experience on my 3G but it is definitely noticeable. If anyone is interested in this I can report back again in a couple of days when I do more clicks.

 

Yup, safety always first.

 

Thanks for the followup.
As I have said before, most of my experience comes from earlier work on cars that did not have sophisticated electronics. I was actually wondering if the manufacturer could do what you suggest, i.e. program the engine to power down slightly during shifts. So I was thinking someone might correct me! I still feel though that my comments about heat being the enemy is really still true. Carry on........

 

I had Z1 in my 2004 TL as factory fill and did the 60K change and every 30K after. At 100K trans failed and I got a refub filled with DW1 fluid.

Throttle closes on the TL during shifts, it has since 2004 models to help save transmissions but they still are failing. Acura's transmissions don't like to coast very much and apply engine braking quite often, a contributor to heat that breaks down OEM fluids.

There's a huge discussion about all the internals on the 3G section if you are inclined to look.

 

Good to see some discussion around the ATF fluid on the 4G forum! I am a former 3G owner and have recently bought a 4G after I was rear ended and my 3G was totaled out.

I am going to put Redline D6 in my 2012 TL this coming week. Rather that do a 3x3, I like to do a full exchange by unhooking the ATF lines (going to the cooler) and let is suck in new fluid (from a jug) while pumping out the old fluid (into a bucket).

Can someone please tell me the direction of fluid flow in the ATF cooler lines? I need to know which line on the transmission is the 'output' and which is the 'input'. There are 2 fittings coming off the 6AT - one points towards the driver's side tire (connected to the filter) and one points towards the radiator. Can someone please tell me (with certainty) which one is the input & output?

 

Forgive my ignorance, but in an automatic transmission, what clutches are there? In a manual transmission, the clutch is what connects the engine to the wheels. In the case of an automatic transmission, this is now replaced with the torque converter, utilizing the transmission fluid as a means of producing power. The only other clutches I could think of would be the synchromeshes for each gear to bring the two mating gears to the same speed.

So by switching to a fluid with less friction modifiers, we're effectively speeding up the rate at which the two active gears mate, which would give the feel of increased shift speeds, correct? Or conversely, if we're running with OEM fluid which has a lot of friction modifiers, or if we're using old broken down OEM fluid (which raises another question of what exactly is breaking down in the fluid over time to cause all of these issues on the 4G 5/6AT and why?), the gears are now mating at a much slower speed, giving off that jerky feel between shifts, because the engine speed hasn't fully matched the transmission speed yet.

Feel free to correct any of my rambling, as it is all purely theory at this point. I've never torn down an engine/transmission before to analyze the components, but would absolutely love to.

 

In AT all gear sets stay engaged at all times and stacked clutch plates open and close to select the gears. Lots more clutch plates on an AT than the single large plate in a MT.

 

What happened to your transmission that was a result of using a non-OEM fluid?

Thanks for the explanation. I did some research on clutch packs and understand a lot more now.

 

one guy bought atf from online and it turned out to have jelly like beads in the fluid that messed up the trans! I'd highly recommend you run any aftermarket fluid through a strainer in the funnel.

DW1 is pretty decent fluid.

 

How did this work out? Were you able to DIY flush?

I want to change the diff and tranny fluid in my TL.

Since my post above in 2014 I have been rocking Redline fluids in my E46 BMW and I am in love. The price is a bit boutique but the performance is worth it. Transmission and engine oil, and power steering fluid in that car and everything is slick and smooth.

No need to run this liquid gold "through a strainer" to get out jelly.

 

It worked out well. It did not 'suck' and in the intake hose so I just let it pump out about 1 gallon, then refilled a gallon, then let it pump out another gallon, and refilled. It started running clean at the end, so I probably exchanged about 95% of the fluid.
My shifts are better, but I am sill getting the bounce after the first 2 shifts. I used 6 qts of D6 and 2 of Racing - I wish I had gone with straight Racing Type F.
You can see my pics in this post:
https://acurazine.com/forums/fourth-...shifts-940501/

 

Seeing that there is some interest from owners here to use 3rd party ATFs, I will just chime in to report on my experience. I've been running a mix of Redline Lightweight Racing and Redline Racing ATF in my 09 TL since late 2014. There have been no issues with my transmission. I am also convinced that the performance is better (ie. slightly quicker and more decisive shifts). I already did an ATF change after nearly 30k and I wish I had waited longer because the fluid that came out looked decent.

Since I first started using Redline, I've driven about 60k km.