Fluid alternatives for notchy shifting?

[phdibart]

I have a '23 4BW with the 6M. It's my understanding that these Tremec TR6060 transmissions are known for notchy 1-2 shifts, especially when cold. There's an older post here at ************** about the same shifting issue in an ATS-V.

I've noticed the transmission can also be a little notchy with low speed shifts. When I'm nailing it, there's no notchiness at all, but driving around town in traffic it can be a little bit.

Do you all have similar shifting in your BWs? Has anyone tried a different fluid like Redline D4 ATF, which is Dexron III rated? Or Tremec's HP-MTF? If so, which fluid and did it improve shifting? Will using a non-GM Dexron III fluid void the powertrain warranty?

 

[Tall Steve]

I never had any problems with the A10 in my 4BW... #10speed #shiftingisnotallitscrackeduptobe
Me:

Just kidding guy!

There is a few threads talking about this, but I can say that the 6 speed in my 5BW is like butter......

 

[rubberduck]

There is a few threads talking about this, but I can say that the 6 speed in my 5BW is like butter......

 

[Tall Steve]

View attachment 22480

 

[daviddi92]

I also have a 23' 4BW that I bought in May. Now that the temps in the Chicagoland area are starting to drop, I notice the second gear notchiness. Have been paying close attention to make sure there are no grinds and have considered changing the fluid to something else. Watching trans temp, once I see it hits about 95+ degrees, it gets considerably smooth and no issues.

When it's cold, I always think about the second gear shift which gets annoying.

 

[minn19]

I had the same problem with my 6MT ZL1 1LE. I used Redline oil and it helped a bit. Not night and day, but better when cold.

 

[phdibart]

I had the same problem with my 6MT ZL1 1LE. I used Redline oil and it helped a bit. Not night and day, but better when cold.

Do you recall which Redline oil you used?

 

[phdibart]

When it's cold, I always think about the second gear shift which gets annoying.

Exactly.

 

[SynisterAZ]

Coming off an SS with that stupid ass 1 -> 4 emissions shift when driving normally, the 2nd gear in this car could never come close to that.

 

[phdibart]

Coming off an SS with that stupid ass 1 -> 4 emissions shift when driving normally, the 2nd gear in this car could never come close to that.

Ha, yeah. I've only heard about that monstrosity of an idea. That must have been absolutely awful.

 

[minn19]

Do you recall which Redline oil you used?

This came up when I searched for the CT5-V BW. I’m pretty sure it’s the same as what I used in ZLE.

D4 ATF

Our most versatile ATF, use where Dexron III®, Dexron II®, Mercon® and Mercon V® fluids are recommended, provides a GL-4 level of gear protection

www.redlineoil.com

 

[MatthewAMEL]

HP-MTF is what I switched to in the Camaro. Not many days of cold shifts in Orlando.

I already have HP-MTF to put in the Blackwing during the xmas/new year break of HPDE/AutoX.

 

[phdibart]

HP-MTF is what I switched to in the Camaro. Not many days of cold shifts in Orlando.

I already have HP-MTF to put in the Blackwing during the xmas/new year break of HPDE/AutoX.

Did you notice improved shifting after switching to HP-MTF?

 

[MatthewAMEL]

Did you notice improved shifting after switching to HP-MTF?

Yes(?) I say it that way because I didn't really have any issues before the switch. During street driving an occasional hitch between 2-3 went away after the switch.

Kinda like the guys who will switch to Stainless brake lines and then swear their pedal is 'more firm'. It's really not, it's either placebo effect or because you just put in fresh brake fluid with a bleed.

Honestly, I originally did the switch after calling TREMEC and talking to them about my use case (lots of track/AutoX) and transmission longevity. The HP-MTF isn't ATF (like the GM Dexron) so it behaves differently in the transmission and gets rid of some of the cons of using ATF in a manual (fluid expansion).

 

[Andi]

There is not a problem to solve; what y'all are describing is a natural quirk of the car. It's a heavy car with a lot of power and torque, and has an appropriately heavy-duty transmission.

 

[Mcard23]

I tried redline in my 6MT Camaro SS and was not a fan. Ended up running Driven AT3 and was a big improvement over OEM or the redline IMO. (Buttery smooth while daily driving in Michigan winters as well as warm summer track days)

 

[phdibart]

I tried redline in my 6MT Camaro SS and was not a fan. Ended up running Driven AT3 and was a big improvement over OEM or the redline IMO. (Buttery smooth while daily driving in Michigan winters as well as warm summer track days)

It's kinda funny you should say that. I've read Vette, Challenger, and Blackwing forum posts on the Tremec 6060, and it's all over the place. Some swear by Royal Purple Synchromax, others Redline D4, and yet others Tremec's own HP-MTF.

Like @Andi said, this may just be the way these trannys work. And I'm kinda leaning that way after giving this probably too much thought. I mean, the BWs are a road legal track car, so should we expect it to drive like regular manual transmission car? My Saab 9-3 was smooth as butter in every shift, but it also didn't have 445 lb-ft of torque.

To that point, in my short time with this thing, I've noticed it doesn't like (1) low RPM shifts or (2) slow shifts (up or down, but mostly down). And this makes complete sense. It's not bad at low RPM or when shifting slow, it's just not at it's best, is how I would characterize it.

My best buddy who was a Cadillac tech back in the Northstar days said when I mentioned this to him, "You have a track car. It won't drive like a normal car. Use what GM recommends, don't change a thing, and relish every shift." He had a Honda CB600RR bike for reference, which he said was awful to drive around town, partially because it would wind out to 88mph in first. That bike wasn't made for the road. And neither were the Blackwings.

 

[BimmerFan]

Watching trans temp, once I see it hits about 95+ degrees, it gets considerably smooth and no issues.

How do you see trans temp?

Coming off an SS with that stupid ass 1 -> 4 emissions shift when driving normally, the 2nd gear in this car could never come close to that.

OMG, my Corvettes had that. What a pain. Fortunately, easily rectified with a bypass resistor.

Kinda like the guys who will switch to Stainless brake lines and then swear their pedal is 'more firm'. It's really not, it's either placebo effect or because you just put in fresh brake fluid with a bleed.

LOL, thank you for that. I concur.

So, anyway... many years ago, I bought an old BMW with destroyed synchros in most of the gears, and my mechanic suggested adding Ford limited slip additive. I did, and after a couple thousand miles, it really did start to improve. I'm not suggesting it here other than as food for thought. If it messes up your car, it ain't my fault.

The issues that many of us have with the notchiness and even grinding is the synchros not, um, synchronizing properly, either d/t temperature, wear, speed of the shift, speed of the input shaft and/or what day of the month it is. Every transmission that I've ever had in my 50-something cars that was put into a high performance car (i.e. not a Honda) had some kind of notchiness associated with it. As @phdibart suggested, these are not normal cars and you shouldn't expect it to act like a normal car.

 

[Mcard23]

It's kinda funny you should say that. I've read Vette, Challenger, and Blackwing forum posts on the Tremec 6060, and it's all over the place. Some swear by Royal Purple Synchromax, others Redline D4, and yet others Tremec's own HP-MTF.

Like @Andi said, this may just be the way these trannys work. And I'm kinda leaning that way after giving this probably too much thought. I mean, the BWs are a road legal track car, so should we expect it to drive like regular manual transmission car? My Saab 9-3 was smooth as butter in every shift, but it also didn't have 445 lb-ft of torque.

To that point, in my short time with this thing, I've noticed it doesn't like (1) low RPM shifts or (2) slow shifts (up or down, but mostly down). And this makes complete sense. It's not bad at low RPM or when shifting slow, it's just not at it's best, is how I would characterize it.

My best buddy who was a Cadillac tech back in the Northstar days said when I mentioned this to him, "You have a track car. It won't drive like a normal car. Use what GM recommends, don't change a thing, and relish every shift." He had a Honda CB600RR bike for reference, which he said was awful to drive around town, partially because it would wind out to 88mph in first. That bike wasn't made for the road. And neither were the Blackwings.

You are right, it's always funny how many different people swear by different brands etc. they are loyal to when talking fluids. Just sharing my personal un-emotional experience - I stick with OE for diff and oil. The trans definitely liked the AT3 better than OE in cold weather (and was recommended by a GM engineer who also tracked his 1LE)...my Camaro saw 30+ track days and 62k miles (many of which were daily driver duty on Michigan roads) under my ownership so it saw some abuse and I think it's a pretty good benchmark. The only time I ever had a trans issue was on track and when Redline was in the car that was only ~6 months old. Fresh fluid and 3 weeks later beat the hell out of that car at Mid Ohio for two full days and never had another issue. I'm not running to switch the fluid in my 5BW by any means but will likely try the AT3 next year when I do all my pre track season fluid swaps. Thankfully I've only every driven manual performance cars so I wouldn't know anything else in regards to "how should it feel" lol

 

[mfbmike]

I've come to expect it in cars after a cold start. It's been the case with numerous cars - Porsches, BMW's, this one, etc. with numerous attempts at changing fluids to get rid of it.

Fluid changes have done little to nothing to change it and any less notchiness in the cold 1-2 shift when cold is usually either placebo or inconsistent.

Once it's warmed up, 1-2 is fine. It's not even awful when cold but I do know what OP is referring to.