Ongoing G8 GT Trans Issues -- Looking for a GM Dealer!

[NAiLs00]

I've got an '08 G8 GT with just over 20,000 miles on the clock, and I've been having issues with my trans since I bought her at 153 miles. I've had it to the dealer at least 6 times, if not several more, for the same issue, but they claim they can't find the problem. They performed a service bulletin for some seals in regards to a flare shift, but that didn't fix it. I even had to convince them there was a bulletin in regards to the flare shift... They also claimed to have updated the computer (or at least checked it) on just about every visit.

The extent of my problem:

Harsh shift from 1-2
Flare shift from 2-3

These only happen when the trans is cool. It is best noticed in Sport Mode, but it can happen in regular drive mode. I have noticed oddities if I use manual select, too.

I'm taking it back to the dealer on Monday to let it sit for 5-6 hours, then come back and take it for a short spin while she's cooled off.


I'm kinda pissed because even after getting the owner of the rather large dealership involved, they still can't seem to help me. They've done other service work on my car just fine, so I'm slightly hesitant to find another GM dealer.... but that's why I seek out someone here who may know, or works at a dealer as a mechanic and wouldn't mind checking out a fellow member's car.

Your help is appreciated!

-Brian

[NAiLs00]

I must be retarded and can't find the edit button... lol

I live in north eastern Milwaukee. I figured this might be helpful.

[Holeshot]

Find someone with HP Tuners buy them the credit for your car and let them tune it correctly. WestBend Dyno. Tom does great miracles with HP

[NAiLs00]

I've wanted to do a tune, but the way the trans acts I almost want to fix that before the tune... Basically for warranty purposes. I know a tune will help a lot all around and may even rid of the problem entirely. I've got other mods that I'd like to do too, so that's why I'd hold off on the tune also. But in all seriousness, thank you for a nearby reference. I'm going to keep West Bend in mind. :)

[Yooformula]

sorry but what does "flare shifting" mean? if you think tuning will solve it, why not tune it now then retune later after more mods? beats having to deal with an improperly shifting car imo.

[NAiLs00]

When I mention flare shifting, it's what an auto trans isn't supposed to do... which is bumping the RPM's up like 300 extra RPM's during the shift. It's pretty bad. I got it to happen twice with the dealers 10+ year trans tech in the car, but he wasn't paying attention the first time, and the second time he claimed I lifted off the gas.

I can't say for certain if any tuning will help permanently, though I think it may only mask the problem for a small amount of time. The harsh shifting started more recently, so it's signs there is more wrong with this trans.

I honestly don't have a lot of cash to pay for a busted trans if I mod it, that's why I'm relying on warranty. Paying for my wedding is truly draining my funds. LoL

[GTO RLY?]

Warranty? The thing can't be more than 2 years old...

[BAD LS1]

Sounds alot like tm intervention to me with the flare. These things don't shift the hottest stock and always error to the soft side than a solid thud into gear. I don't know shit about the guts that could cause the hard shift out the blue.

[NAiLs00]

Warranty? The thing can't be more than 2 years old...

I'm just referencing warranty because you mod it and you can say good bye to the powertrain warranty. :( GM has been requiring dealers to send a snapshot of the computers and they can quickly tell if it was toyed with. I can't afford to pay for a new trans if it breaks, at this time. She isn't even 2 years old yet.



Sounds alot like tm intervention to me with the flare. These things don't shift the hottest stock and always error to the soft side than a solid thud into gear. I don't know shit about the guts that could cause the hard shift out the blue.

I heard about the obnoxious amount of TM in these things. I honestly can't wait to get it tuned down the road to open it up. I'm pretty scared of that harsh shift though. Today it felt like it was gonna blow because it shifted so hard.

[NAiLs00]

I'm going to see if I can capture some video this morning on my way to the dealer. I don't know if it's going to turn out, though. I have only used the video function of my DSLR a few times. I'm hoping when I go back to them early this afternoon, that it flares and shifts hard again. I'm still looking for a dealership if someone knows of one or works for one.

-Brian

[BAD LS1]

By chance do you have an intake on it or an drop in oiled A/F?

Not a clear example of your situation, but if you alter airflow via a intake with a shitty maf location or oil covers the maf cross hairs, you may open up oppurtunity for odd shifting behavior due to the torque calculations being off by alot which dicks with line pressure. Even if you have none of the above, something stands to reason something in this area might be to blame, id look at LTF's with a scanner to see if they are jacked for some reason too like a loose intake coupler, it will affect it the same way.

You may also notice some flare at cruise too due to the AFM engaging/disengaging because the PCM blips the throttle to make the switch more seamless, which looks and feels like trans slip at times, just throwing that out there too.

http://www.hptuners.com/forum/showthread.php?t=22377&highlight=g8+maf

[NAiLs00]

That is something to look at for sure. It is definitely something that didn't come to mind, so I'll have to search the boards for someone with a scanner. I do have a Vararam intake, though my flare shifting started from almost day 1 and the harsh shifting started this winter. I've had the intake on sine Vararam came out with their intakes for the G8. Could this still be the case? I shall check all connections when I get the car back to make sure I don't have a leak, though the intake tubing is only like 6 inches so there isn't too much room for error. Also, would it only happen when the trans is cool and not warm if this were the case? I'm thinking it's plausible because maybe as the motor warms up, what if it is making that better seal with the intake?

I also got a video of it shifting hard, but didn't catch the flare. Of course the second I put the camera down it happened. LoL. Now I have to figure out how to compress it since 46 seconds came to over 80MB.

[BAD LS1]

Tell ya whats the easiest thing to do is... Remove the vararam and isntall the stock intake, but use rubbing alc on a q-tip and lightly clean the maf cross hairs and place it back in the system, secure all clamps and remove any fuse from the engine bay fuse block that says it has anything to do with the PCM including TCM fuse for 5 min, install them and test it for your trans issues. This resets any of the fuzzy logic adaptive memory. The flare im pretty sure is just the calibration, harshness i feel might be caused by the intake. Ive tuned 1 G8 with a vararam and the trims were + 12 at cruise, which indicates lean by 12% and that means the MAF calibration is OFF because thats the only thing you changed was airflow through it.

[GTO RLY?]

If all you have is a Vararam, it won't void the warranty. If they're fags about it, throw the stocker back on and tell them to STFU. And no, they can't tell if you've modded the car by just scanning it with a Tech2, unless you've flashed in something different.

[NAiLs00]

Tell ya whats the easiest thing to do is... Remove the vararam and isntall the stock intake, but use rubbing alc on a q-tip and lightly clean the maf cross hairs and place it back in the system, secure all clamps and remove any fuse from the engine bay fuse block that says it has anything to do with the PCM including TCM fuse for 5 min, install them and test it for your trans issues. This resets any of the fuzzy logic adaptive memory. The flare im pretty sure is just the calibration, harshness i feel might be caused by the intake. Ive tuned 1 G8 with a vararam and the trims were + 12 at cruise, which indicates lean by 12% and that means the MAF calibration is OFF because thats the only thing you changed was airflow through it.

That's quite interesting. When I find a little time and am up at my parents house in Sheboygan, I'll give this a shot. My question though, is why would it be fine for like 4 or 5 months, then suddenly start happening? Did the computer take that long to realize it? I too agree the flare is all in the tune and I wish GM would step up to it. I had a service bulletin done that replaced some seals, but that didn't fix the flares.




If all you have is a Vararam, it won't void the warranty. If they're fags about it, throw the stocker back on and tell them to STFU. And no, they can't tell if you've modded the car by just scanning it with a Tech2, unless you've flashed in something different.

Nah, they're not sticklers for my intake an exhaust. They even complimented my car many times. One dude heard it start up from a little ways away and thought it was a Corvette... HA... I wish.

I was just mentioning the PCM / TCM would void the warranty. It'll stick out like a sore thumb if it has been touched.




I figured I would upload my video to YouTube, since that seemed to be the easiest way to compress it. The 3rd acceleration, right at the end, is where it shifts hard. Click it to view the 720p version since I don't think links on the board will let you.


EXdIwFhxnJA

[BAD LS1]

Yeah im not sayimng thats the answer to the issue, but it can certainly play a role. The reason it may have taken some time is the 5 o clock shadow of filter oil had to develop on the maf crosshairs to finally push it over the edge. Its worth a shot before a dealer blames the intake or discovers this very thing as the root cause to say, this visit is NOT on us.

[NAiLs00]

Alright... I'm finally back from my adventures today. I had to get my tires replaced since they wore down in 18000 miles. Argh!

Anyway, I took a test drive with the service manager, and I got the problem to happen twice with him in the car. I'm not very pleased with what he said, and I am not sure what direction to take it after I do my MAF testing.

He first off said I accelerated pretty hard. Well... I can't say 2000-2500 RPM's is hard by any means, especially when you gotta turn into traffic on a daily basis. If I want to grandpa it and keep it under 1500 RPM's, it's going to take a couple blocks to get up to speed.... not gonna happen.

Then I finally convinced him that his answer was stupid, so he then said there is absolutely nothing that he can do since the trans is computer controlled, and if there really was a problem, the computer would have thrown a code and stored it. Well... I call BS that there isn't a problem since the problem happened right in his face.

Finally when I went to finish up and drop him off back at the service garage, I brought up his aforementioned case again. I also mentioned that yesterday it shifted so hard that it felt like the trans was going to blow up. His answer, "Maybe that would actually be a good thing..."

What happened to preventative maintenance? I DON'T want this to happen. I DON'T want to be stranded on the side of some road b/c my trans blew up. Ugh!!!

The last thing he told me, was he would write up a report and send it off to GM to see what they think. I really hope something comes of it because this is beyond dumb.


I shall still test the MAF thing. I'll even try to take a close-up pic of the MAF crosshairs and make sure there really isn't oil on it. I know it can happen, and I'm doubting it in my mind b/c I hope that isn't the issue. I would definitely be flabbergasted if it was. LOL.

I'm still lookin' for any dealer suggestions, though. I don't know if this particular dealer will be able to help me, even when getting the owner cracking the whips.

[wrath]

The 6L80e behaves differently than your normal 4 speed. There is no sprag/overrunning clutch so there is no "lurch" when shifting into 3rd gear for example. It's all clutchpack to clutchpack shifting so it behaves a bit different. It has adaptive shifting that tracks driving behavior and other things like transmission fluid temperature. The transmission will preserve itself. There is a team of engineers that tune these transmissions.

If you lift when it shifts it has difficulties doing the calculations to do RPM matching that it always does in an attempt to be a seamless shift. The same is true if you accelerate when it's about to shift.

The harsh shift doesn't surprise me when in sport mode, it's not trying to preserve comfort and you're talking a serious RPM difference for the vehicle speed. The flare does surprise me a little bit but I suspect you'd find want you're feeling in all G8GTs but not in the GXPs. I'll ask someone I know about it.

[BAD LS1]

Yeah someone should have called tech assistance at the dealer to ask if there is any other recourse or reported encounters. I mean if you have the infamous vibration in a G8 you gotta replaced like 20 things first in order to get one of the "specially balanced" drive shafts lol. Cant say im surprised by the dealers responce, most are not driveability experts which should be a big part of their on going training IMHO.

^^^The 6l80E shifts like dog shit stock because its calibrated twoards comfort and smoothness, not everyone is interested in a snappy performing auto so it has to appeal to the masses. Ive had good success with that 6l equipped G8 and a L99 camaro, but they are a huge learning curve. I was able to get it to provide a nice bump into each gear, rips the tires loose into 2nd at WOT and the tapshift feature much quicker to respond.

[NAiLs00]

Well, the last word I got from the dealer was that they were going to write up something to GM. To this day, I still haven't heard anything. I suppose I'll have to call later this week to find out.

I also haven't had a chance to look at the MAF, but I am going up by my parents place tomorrow, so I'll have a little garage time to do that.

I'll keep ya updated.

[NAiLs00]

Alright. I was able to snap some pics of the MAF crosshairs... and see the results below:


Click Image for Larger View!!


http://www.gameagon.com/images/G8/m-cs.jpg (http://www.gameagon.com/images/G8/m-c.jpg)

[BAD LS1]

If those are untouched, they look perfect. No five o clock shadow there. Id still toss the stock box back on and try it... those vararams play hell in tuning and maf turbulence im sure u have read in the past... just the process of elimination.

[NAiLs00]

Yea, the only thing I did was sharpen them and make them clearer. I had a hell of a time focusing on something so tiny not using a tripod. I didn't have time to try slapping in the stock box, though.

[Slow Joe]

He first off said I accelerated pretty hard.


With a comment like that if I were you I'd hope that the report he's writing to GM isn't telling them that you're an abusive driver, and asking that they blacklist your vin from warranty claims.



I DON'T want to be stranded on the side of some road b/c my trans blew up.

It's called GM Roadside Assistance, good for the duration of your bumper to bumper warranty. You get a free loaner too... :durr