LT6 Married To Revised DCT

[John]

While we have heard all the following pieces here and there before , including the following chart showed at the Bash and we put up here last week, we thank GM Authority for putting all of the LT6’s revised DCT info in one place.

Corvette chief engineer Jason Holder confirmed the improved transmission for the 2023 Corvette Z06 during a presentation at the recent National Corvette Museum Bash in Bowling Green, Kentucky. According to Holder, this version of the transmission will feature an upgraded clutch pack for increased torque capacity, along with a strengthened casing to handle larger lateral loads. The bell housing was also redesigned to accommodate a larger oil sump, allowing Chevy to ship the Z06 with track-ready oil levels. On the C8 Corvette Stingray, drivers are advised to add an extra two liters of oil if they plan to take the vehicle on a track to ensure the engine received proper lubrication under high load.

The Corvette Z06’s eight-speed transmission will also feature larger diameter output shaft flanges to support the model’s high-strength half shafts, along with a 5.56:1 final drive ratio, which is about seven percent shorter than the C8 Corvette Stingray’s factory gearing. The Tremec TR9080 eight-speed dual-clutch transmission on the C8 Corvette Stingray is ragged with RPO code M1L, however this improved version for the Z06 has a different RPO code of M1M.

https://gmauthority.com/blog/2022/05...-transmission/

[JB]

Good to kniw the corvette engineers have beefed up the dct for the 670 hp LT 6.

Of course we all knew it would yet its good to know some of the details.

[John]

We heard here the first part of that DCT strengthening way back a day after the reveal in a video with EddieX getting a walk around with Aaron Link and Alex MacDonald.

[Milliwatt Rob]

I hope the DCT has been checked for its ability to endure the flat plane crank vibrations.

[John]

Oh yea of little faith. What do you think the 300,000 street miles, the many race races run including LeMans, and the 24 hour continuous at full speed event on the track was…

[Milliwatt Rob]

Notwithstanding extensive road testing, sometimes things sneak through to early production. 2015 Z06 overheating comes to mind.

Then there was my father's 1978 Oldsmobile diesel.

[Jetdriver]

This isn't your Fathers Oldsmobile!

[P-Tree]

Notwithstanding extensive road testing, sometimes things sneak through to early production. 2015 Z06 overheating comes to mind.

Then there was my father's 1978 Oldsmobile diesel.

https://www.nytimes.com/2008/05/18/a...es/18RUST.html

This is a great article of how GM diesels were bad. Long story short, they took the existing gas V8, tried to convert it to diesel, and failed instead of creating a new diesel offering. But, things like this have a lingering effect.

[Phil1098]

Lots of things pop into ones mind because of what has happened in the past that shouldn't have. I asked about bad vibes because even though it has magnetorheological mounts to hide them from the driver, they are still happening inside the engine. One of the reasons I asked was back in the 90s John Deere had crankshaft issues on the biggest combine they made. After about 5,000 hours the end of the crank would fracture and fall off. It wasn't entirely rare either as I knew two farmers alone that it happened to. It was hard to believe something as big as a crank in a combine could fail, but they did...............

[P-Tree]

I asked about bad vibes because even though it has magnetorheological mounts

It doesn't have MR mounts, confirmed recently.

[Milliwatt Rob]

As the DCT is bolted onto the engine, the kind of mounts attaching the engine/ transaxle to the chassis makes no difference to the engine vibrations transmitted to the transaxle. No?

[P-Tree]

As the DCT is bolted onto the engine, the kind of mounts attaching the engine/ transaxle to the chassis makes no difference to the engine vibrations transmitted to the transaxle. No?

Not a mechanism engineer, so can't say
I've posted up a few threads about FPC info and the like. Think this is another thread where the worries about the vibrations are being blown out of proportion.

[Phil1098]

It doesn't have MR mounts, confirmed recently.

Really?

https://www.midenginecorvetteforum.c...mounts-part-ii

[Phil1098]

Not a mechanism engineer, so can't say
I've posted up a few threads about FPC info and the like. Think this is another thread where the worries about the vibrations are being blown out of proportion.

They are not overblown in the least. The world, for decades, has placed a cap on displacement at 5.0 liters for a V8 with FPC. I'm talking Porsche, Ferrari, etc. Ford pushed it to 5.2 on the VooDoo and have since given up, now the LT6 is 5.5. Maybe GM knows something that no other manufacturer could ever figure out, but to act like it's no big deal or is overblown is just not accurate. Bad vibrations inside an engine can destroy it over time.

[3 Z06ZR1]

They are not overblown in the least. The world, for decades, has placed a cap on displacement at 5.0 liters for a V8 with FPC. I'm talking Porsche, Ferrari, etc. Ford pushed it to 5.2 on the VooDoo and have since given up, now the LT6 is 5.5. Maybe GM knows something that no other manufacturer could ever figure out, but to act like it's no big deal or is overblown is just not accurate. Bad vibrations inside an engine can destroy it over time.

The VooDoo had oiling issues from mag reviews it was a problem. Long term wear from high RPM's used to be issue. Hope none of this happens. Love the Z06 it needs to be a success. I'm sure it will be.