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      10-10-2012, 10:41 AM   #1
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Intermittent slow DCT shifting?

At a track day this past weekend, I noticed that my DCT was shifting flawlessly during the first few laps, had a slight delay during the middle lap or two (on upshifts), and then acted perfectly fine for the final couple laps. has anyone ever experienced this?

i had the traction control off, and the shifting intensity was set all the way up to 6.
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      10-10-2012, 11:08 AM   #2
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Got that only once on a very hot day. I guess it is the tranny overheating. Other folks that run in hotter climates have had the issue.

a little and you'll find some more info on the topic.
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      10-10-2012, 02:04 PM   #3
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I've had overheating problems every time I went to the track with temperatures in the mid-90s and up. I've had both engine oil overheating and DCT overheating issues.

Symptoms of the DCT overheating are:
* slower than usual shifting
* not shifting at all
* shifting by itself to higher gears
* loss of lower gears

By the time you get the above symptoms (except slow shifting), you would typically get an overheating warning message.
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      10-11-2012, 07:37 AM   #4
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Unless you've been running something longer than a 20 minute DE session your DCT shouldn't overheat. How many shifts are you doing per lap? I've never had a heat issue in 100 degree temps but you do have to manage the car. You can't keep the tach pinned at the redline the entire time.
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      10-11-2012, 10:18 PM   #5
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Quote:
Originally Posted by bigjae1976 View Post
Unless you've been running something longer than a 20 minute DE session your DCT shouldn't overheat. How many shifts are you doing per lap? I've never had a heat issue in 100 degree temps but you do have to manage the car. You can't keep the tach pinned at the redline the entire time.
Damn...that's the most fun pinned! Only had it once in 101 temps at ORP- which has lots of shifting due to 17 turns and many elevation changes. Otherwise, this DCT has been flawless. This driver melts before the gearbox after 25min sessions...
All should be ok. Just pull up for a few laps or wait till next session. When it gets really hot you get the warning light in advance as was mentioned.
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      10-12-2012, 07:12 AM   #6
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Quote:
Originally Posted by NRBRNG View Post
Damn...that's the most fun pinned! Only had it once in 101 temps at ORP- which has lots of shifting due to 17 turns and many elevation changes. Otherwise, this DCT has been flawless. This driver melts before the gearbox after 25min sessions...
All should be ok. Just pull up for a few laps or wait till next session. When it gets really hot you get the warning light in advance as was mentioned.
There are a couple of corners on the tracks here in TX that are kind of long, slow corners where you can drop down into 2nd but you're near the redline for awhile. That will cause the engine oil and subsequently the DCT to get really hot.

I could down shift into 2nd later into the turn but not sure if I'm comfortable with that. But I haven't had a ton of seat time in my E90 to really build a lot of comfort. I am comfortable mid-corner shifting with my 6SP 330 because I'm in control.
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      10-12-2012, 01:44 PM   #7
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Quote:
Originally Posted by bigjae1976 View Post
Unless you've been running something longer than a 20 minute DE session your DCT shouldn't overheat. How many shifts are you doing per lap? I've never had a heat issue in 100 degree temps but you do have to manage the car. You can't keep the tach pinned at the redline the entire time.
I agree that the car should not overheat if you're running short sessions. I'm fighting the overheating issue right now. I even installed an upgraded oil cooler and DCT cooler in my car with no significant difference. I'm thinking something is wrong with my car and trying to pin point the root issue. I'm obviously not cruising on track at 3K RPM but I'm not very long at red line either... short time on long straights while accelerating and shifting to next gear and short time coming out of corners, that's it. I don't even use 2nd gear on track. I'm pretty much always in 3rd and 4th with short time in 5th on long straight.

I checked my videos from a few weeks back in mid-90s temperature, it took 8 laps (~13min including 1 warm-up lap) for the car to overheat at which point I pulled back. And this was with upgraded cooling. Oil temperature needle was almost touching the 300F and I got warning that only higher gears were available.

If nobody else is having this problem than my only conclusion is that something is wrong with my car...
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      10-12-2012, 03:47 PM   #8
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Would going from S6 to S4 allow your DCT to run cooler?

Quote:
Originally Posted by Ti-Jean View Post
I agree that the car should not overheat if you're running short sessions. I'm fighting the overheating issue right now. I even installed an upgraded oil cooler and DCT cooler in my car with no significant difference. I'm thinking something is wrong with my car and trying to pin point the root issue. I'm obviously not cruising on track at 3K RPM but I'm not very long at red line either... short time on long straights while accelerating and shifting to next gear and short time coming out of corners, that's it. I don't even use 2nd gear on track. I'm pretty much always in 3rd and 4th with short time in 5th on long straight.

I checked my videos from a few weeks back in mid-90s temperature, it took 8 laps (~13min including 1 warm-up lap) for the car to overheat at which point I pulled back. And this was with upgraded cooling. Oil temperature needle was almost touching the 300F and I got warning that only higher gears were available.

If nobody else is having this problem than my only conclusion is that something is wrong with my car...
Odd. I can run 20 minutes at a reasonable pace and no limp mode. I'd get your car checked.
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      10-12-2012, 04:37 PM   #9
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Quote:
Originally Posted by bigjae1976 View Post
Would going from S6 to S4 allow your DCT to run cooler?
I'm not that good yet to run without DSC in S6... I run MDM on (euro) in S4 mode already.

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Originally Posted by bigjae1976 View Post
Odd. I can run 20 minutes at a reasonable pace and no limp mode. I'd get your car checked.
Yeah, that's the conclusion I'm converging to... something is wrong and I need to find what it is.
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      10-12-2012, 07:51 PM   #10
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Quote:
Originally Posted by Ti-Jean View Post
I'm not that good yet to run without DSC in S6... I run MDM on (euro) in S4 mode already.



Yeah, that's the conclusion I'm converging to... something is wrong and I need to find what it is.
MDM sure ain't helping your brakes. I'd run with DSC off at the track and M Mode on. Might be some mysterious thing that helps with the overheating.
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