SRT8 Transmission Questions! (Moved)

[srt8man]

I bought a 2008 300C SRT8 last November, and overall I have been very happy with it. The only thing I'm not happy with is the transmission. It is very inconsistent. I would like to know if anyone else has had these problems I'm experiencing and if the dealer should be able to fix them.

The biggest problem for me is the 1-2 upshift. There is never any hesitation, but sometimes it shifts way before redline during WOT, even as low as around 5500 RPM. I thought that using autostick was supposed to make it hold gears until redline, but this doesn't work either. For a while, I thought it was, but that doesn't work consistently. For example, when I slap it into first using autostick and mash the throttle, it still shifts way before redline sometimes, regardless of whether or not there is any wheelspin at the time. Sometimes the 1-2 shift occurs at or near redline during WOT, but I want it to always shift at or near redline. The 2-3 and 3-4 upshifts always occur very, very close to redline during WOT, so there is no problem with those shift points, just the 1-2 shift.

Another problem is the downshifts. I understand that the SRT8 has an adaptive transmission, but it seems that it lacks consistency. Sometimes I get downshifts when I expect them, and sometimes I don't. I can start driving it really hard for some time, and not get the downshift when I want it while at other times I can cruise around town slowly for a while in traffic and get the downshift later when I want it. On the bright side, at least the autostick can be used to get the downshift, but I don't like having to do that all the time.

Has anyone else experienced these problems with the SRT8 transmission? Can the dealer fix the problems? I hope the problems can be fixed without an aftermarket programmer. I've heard about the Diablo Predator, but I want to get it working right without tinkering with an aftermarket programmer. Please, please, please tell me the SRT engineers didn't make my car like this "on purpose".

[acw]

Apparently 2007+ vehicles have updated software (that 2005-2006 vehicles need a flash to get) which is supposed to provide better shifting in D and "perfect" shifting in AS, meaning it will auto shift for you at the "optimum" RPM so you don't over-rev the engine. This means no gear holding and is the reason some 2005-2006 owners don't get the TSB flash (irreversable) done.

See post #2 in the following thread: Update on SRT8 shifting before 6200 in 1st in AutoStick

=shift+5500


Link for the 2005-2006 trans. flash TSB:
Free Flash: The Official SRT8 1-2 delayed shift solution has arrived

BTW, I got the flash done and the shifting in D seems to have improved quite a bit. There were a few stumbles yesterday but I think that was because of ESP activating due to my heavy foot. Try a pull of fuse 11 and test out the shift consistency then.

[srt8man]

Please, somebody bump this topic so I can get some advice. So far it appears that only one person on this forum is experiencing my problem. Even if you are not experiencing the problem, just let me know. I am VERY DISATISTISFIED with the SRT8 transmission and it is really pissing me off! I want consistent 1-2 shifts!

I read through that first thread, and that guy seems to be having the same problem I have, but I cannot find anyone else having the problem where it shifts way before redline (recently it seems like it short-shifts about 50% of the time). I have an 08 so it has the upgraded flash for the transmission, but does not work the way it is described in the TSB thread.

I read through the first 10 pages of the TSB thread, and it sounds like nobody there is having the problem I'm having. (I really don't want to read all 20+ pages of that thread.) Everyone there seems to be reporting that it holds gears until redline when using autostick, which is definitely not the case with my car. In addition, the transmission behaves in the same inconsistent manner in Drive mode at WOT on the 1-2 upshift. It NEVER short-shifts on the 2-3 or 3-4 upshift, regardless of if I'm in Drive or Autostick mode, so why does it short-shift on the 1-2 upshift? I know this is hurting my performance because I can feel it pulling real hard and then BAM, it shifts too soon and the RPMS drop far lower than they should due to the early shift.

The dealer better be able to fix this problem because I'm getting really frustrated at this point! If they can't fix this problem, I may never buy another Chrysler product, sad to say.

Originally Posted by acw

Apparently 2007+ vehicles have updated software (that 2005-2006 vehicles need a flash to get) which is supposed to provide better shifting in D and "perfect" shifting in AS, meaning it will auto shift for you at the "optimum" RPM so you don't over-rev the engine. This means no gear holding and is the reason some 2005-2006 owners don't get the TSB flash (irreversable) done.

See post #2 in the following thread: Update on SRT8 shifting before 6200 in 1st in AutoStick

=shift+5500


Link for the 2005-2006 trans. flash TSB:
Free Flash: The Official SRT8 1-2 delayed shift solution has arrived

BTW, I got the flash done and the shifting in D seems to have improved quite a bit. There were a few stumbles yesterday but I think that was because of ESP activating due to my heavy foot. Try a pull of fuse 11 and test out the shift consistency then.

[Rambit]

Ken, I think the problem here is that there's not a lot of owners of 2008 SRT8's to compare with yet. I never did get the flash for the reason I want to be able to hold a gear. That TSB eliminated it permanently. Many swear by it, but there are a few like me who don't want it. The problem as I understand it is that the tach lags slightly behind. You now upshift at a lower rpm before it bounces off the engine limiter, which is where the 1-2 hesitation came from.

I think the only thing you'll be looking at is the Predator if you want to see any improvement.

Bernie

[barry barco]

Originally Posted by srt8man

I bought a 2008 300C SRT8 last November, and overall I have been very happy with it. The only thing I'm not happy with is the transmission. It is very inconsistent. I would like to know if anyone else has had these problems I'm experiencing and if the dealer should be able to fix them.

The biggest problem for me is the 1-2 upshift. There is never any hesitation, but sometimes it shifts way before redline during WOT, even as low as around 5500 RPM. I thought that using autostick was supposed to make it hold gears until redline, but this doesn't work either. For a while, I thought it was, but that doesn't work consistently. For example, when I slap it into first using autostick and mash the throttle, it still shifts way before redline sometimes, regardless of whether or not there is any wheelspin at the time. Sometimes the 1-2 shift occurs at or near redline during WOT, but I want it to always shift at or near redline. The 2-3 and 3-4 upshifts always occur very, very close to redline during WOT, so there is no problem with those shift points, just the 1-2 shift.

Another problem is the downshifts. I understand that the SRT8 has an adaptive transmission, but it seems that it lacks consistency. Sometimes I get downshifts when I expect them, and sometimes I don't. I can start driving it really hard for some time, and not get the downshift when I want it while at other times I can cruise around town slowly for a while in traffic and get the downshift later when I want it. On the bright side, at least the autostick can be used to get the downshift, but I don't like having to do that all the time.

Has anyone else experienced these problems with the SRT8 transmission? Can the dealer fix the problems? I hope the problems can be fixed without an aftermarket programmer. I've heard about the Diablo Predator, but I want to get it working right without tinkering with an aftermarket programmer. Please, please, please tell me the SRT engineers didn't make my car like this "on purpose".

As for inconsistent down shifts I know you have to back off to a neutral throttle position before it will let you have a lower gear in auto stick mode. Quite inconvenient with the 25 MPH kickdown limit in drive. Alot of times a slower car will kick my ass if i don't get into first gear before running from a 26 MPH+ punch. Trick is to get the thing into gear early so you are not too low in the power band. My old 95 lincoln town car ( 210 HP )will beat my SRT 8 from a 26 MPH punch (in drive) for a few seconds. As for your list of problems I've seen my SRT 8 do alot of weird things that don't make me too happy.

[EricG]

Ken,
I'm afraid that's the nature of the beast with our adaptive transmission. A few WOTs in a row shift it at redline, the predator completely solves it I've heard, and pulling fuse 11 solves the problem right away too. I'm hopefully picking up my Predator and getting a CMR tune today. I've read but cannot verify that the '08 fuse boxes are a little different, so the pulling fuse 11 trick may not be so simple for you, I read there's another way that's as easy on the '08s but you'll have to search for it. Good luck,

Eric

[Rambit]

Originally Posted by EricG

Ken,
I'm afraid that's the nature of the beast with our adaptive transmission. A few WOTs in a row shift it at redline, the predator completely solves it I've heard, and pulling fuse 11 solves the problem right away too. I'm hopefully picking up my Predator and getting a CMR tune today. I've read but cannot verify that the '08 fuse boxes are a little different, so the pulling fuse 11 trick may not be so simple for you, I read there's another way that's as easy on the '08s but you'll have to search for it. Good luck,

Eric

Eric, it's now fuse #2 for the 2008's. I agree though, pulling it from time to time will help. These cars are fast learners!

Bernie

[2007BlackSRT8]

The best way to fix these issues is to get the Diablo Predator tuner. The Diablo tuner raises the shift points to 6400rpm in every gear and raises the kickdown point in first gear to about 35mph. These changes alone made a huge difference in driving around town. By the way, if you don't want to install the tune that comes with the diablo tuner, you can still use it to modify just your shift points on your stock tune.

[srt8man]

Thanks for all of your advice guys. I really appreciate you taking the time to respond to my questions. I guess I have a few choices, Predator, fuse, and possibly a dealer repair/reprogram.

The downshift in Drive isn't that bad because I can always use autostick to downshift. The random premature 1-2 shift during WOT in autostick (and Drive) is what really bothers me, and I'm certain it's not the analog tach readout just lagging behind the actual engine revs. I know when it's time to shift based on the way the engine sounds and the way the car is pulling, and it definitely is not shifting at the right time on some runs. It's still making more power prior to the shift and the worst part is that I have absolutely no control over the shift. (Rambit, you made the right decision not getting the TSB - if it ain't broke, don't "fix" it).

I've been looking through some of the information at 300cforums.com about the Predator, and may get one. This would probably be my last resort though. The thought of reprogramming factory settings using an aftermarket tuner is a little bit scary to me. I don't like tinkering with stuff anymore, and learned many a lesson (including some expensive ones) modding a Mustang Cobra several years ago. I've read lots of posts about different programmers used on different vehicles with different mods and it is all a little bit confusing. Some people have had problems with different programmers, while others have not. For the most part, It sounds like people have been happy with the Predator, but I'm a bit scared to do anthing like that yet.

I just don't understand how the SRT engineers could create transmission programming with such a major problem, if this problem is in fact widespread, can't be repaired by the dealer, and is not limited to just my car. The original programming was causing some (again, the consistency problem) SRT8s to bump the rev limiter, which in my opinion is an unacceptable problem in a high-performance car. Then the engineers came out with a TSB that seems to resolve that shift hesitation problem on the older models, but their solution takes away the ability to hold gears at redline. Although it isn't the optimal solution, I could live with it not holding the gear IF it shifted at redline as they advertise. I would rather be able to control it myself than have it shift prematurely for me.

Maybe I will try pulling fuse #2 as some have suggested helps for the 2008 models. I wonder if I would have to pull the fuse on a regular basis, like everytime I'm caught in traffic and can't drive it the way it was meant to be driven. It would be very inconvenient to have to pull the fuse every day.

Oh well...I will go to the dealer and see if there is anything they can do. If they can't fix it, maybe I'll try using the Predator or pulling the fuse.

Thanks for listening.

Edit: Dumb question: Can fuse 2 just be removed permanently or does it need to be pulled and then put back before I can drive? I guess I have more research to do, but I'm lazy. ha haa!

[Rambit]

Yeah Ken, these cars learn fast and can adapt to a more economy minded mode, which includes shifting BTW. Pulling fuse 2 in your case for 15 seconds clears the adaptive memory. What you have to do right after that is drive with "spirit" afterwards. The problem is it starts relearning all over again, so whenever you feel it's going back to the granny mode just pull it again.

I also think if you did this as soon as possible you're probably going to notice a big difference from what you're experiencing now.

EDIT: Just saw YOUR edit...haha. No, you gotta put it back!!!

Bernie