First the Corvette C7 or C8 dash 1LT, 2LT or 3LT is not a tanned animal skin. The ONLY real leather on a C8 is the GT-2 seat (perhaps the 3LT Drive Mode Wrist Rest!) The other material is either GM's coined name Mulan, which like Chrysler's "Corinthian Leather" was a name created by their ad agency for faux leather.

For the C7 it was accepted by most the 3LT Dash was Mulan and had some issues. The 1LT and 2LT dash also looked like leather as well, as the embossing rolls made it look like "leather." It was leaked that it was bonded leather which was for the C7 Vinyl with 10 to 20% finely ground real leather mixed with the vinyl reason as a filler.

The C7 interior designer talked about the "soft touch" interior materials being real Napa Leather, Mulan or Vinyl. So by deduction since the 1 and 2LT dash had no reported issues (or every view) it was assumed it was Vinyl. If you check the furniture Industry, Bonded Leather is commonly used and each manufacture has their ouwn name. It is wanded not to place Bonded Leather chairs in direct run or near floow heat registers. In fact Vinyl proaply streahces no shriks with heat.

For the C8 it's possible the #LT dash in Mulan (whatever faux leather it is) an the 1LT and 2LT Vinyl. It's GM's coind name and can be whatever!

The C8 is the 1st time where they defined the bolsters even on the GT2 seats are NOT Napa tanned animal hideNapa leather reather then are Mulan. Don't say what the bolsters' are on the GT1 seat only the seating serfice is Mulan but Mulan.

 

When I see pictures of deboned dashes on other cars a majority of them look like the leather has shrunk and pulled away from the base. On the C7 the leather would pull away from the defroster vents and HUD opening and you wouldn't be able to pull it back in place. Having adhesive hold up under these conditions is a tough job even without thermal cycling.

The pictures of the C8 3LT debonded dashes look like the leather is floppy and bubled but like it isn't under a lot of tension. This may be a different problem than the traditional problem of dashes failing.

 

^^^^
The ones I have seen, as you note, do not look like the C7 3LT. The C7 fit more what the furniture industry warns about bonded leather, i.e. keep away from floor heat vents and direct heat because it can dry out and shrink. The C8 looks like the glue failed.

 

if the furniture industry warns against its use, why then, would a company or vendor put the material "bonded leather" if that's what it is, on a dash that is one of the few places that gets this type of heat and has multiple vents adjacent for both hot and cold temps?

 

One would think, the adhesive manufacturers have conducted a multitude of testing in the performance of their upholstery adhesives, including testing in a wide range of temperatures, rate of change in temperature and material used to adhere. If an adhesive failed on a dash sitting in the showroom, then it would fail in the testing.

My speculation is the adhesive failed due to one or combination of the following: poor surface preparation, lack of product application, defective batch of adhesive in the manufacturing or loss of adhesiveness due to expired shelf life.

The bottom line is quality control, no matter what auto manufacturer we are discussing about.

 

I know a leather dash is supposed to be "upscale" but I honestly can't see the reason for it other than a larger profit margin? Of the five Corvettes I've owned I never once looked at a 2LT dash and thought "Wow that looks like crap!". To me a simple solution would be to install a 2LT dashboard in all 2 and 3LT interiors. They could color the stitching if desired during the manufacturing process. No more delamination problems. If my 3LT dash were to delaminate I'd request a 2LT replacement. Whether or not they'd do it I don't know.

 

The 3LT "leather" does have a nicer look that the TPO material used in the 1LT/2LTs (at least to me). But there are high quality synthetic materials that look and feel as good as the "leather" used in the 3LT. It's probably just that many people wouldn't want to pay more for a higher quality synthetic vs leather. I'd be fine with a 3LT with high quality synthetic leather.

 

It smells better than Vinyl and may feel somewhat better. But I agree if the 1LT and 2LT don't have an issue why would they not use it beit Vinyl or Polyurethane fabric also like GMs coined name Mulan and Chryslers Corinthian faux leather. All refereed to as "leather" even thought it's faux leather.
BTW, the "Ultraleather" I selected for my street rod is a very high end, Polyurethane faux leather. In my case quoted the same price as real leather but it's as soft as the best Moroccan woman's glove leather. The compony prides themselves as no dead animals used to produce.

Had 3LT, C6 and 3LT 2014 C7 but GM got cheap in 2016 and made the 3LT look like a patchwork quilt, IMO. So bought a 2LT but did like the seat colored upper dash pad above the steering wheel. I was on the 3LT. So bought and installed. i could not tell the difference my Vinyl dash. Felt soft, no doubt due to the backing on the Vinyl.

So I don't know why GM does not used the same material for the dash in all 3!

ALL 3 interiors below are 3LT. GM got cheap in 2016 so I bought a 2LT 2017 Grand Sport. Unlike my 2014 3LT had to get a special model after 2016 that came with Spice Red to get what I had in 2014.

I decided to add the Upper Dash Pad to match the seats in my 2LT Grand Sport. So bought a 3LT Red Upper Dash Pad


The Faux leather 3LT Red Upper Dash Pad and 2LT Black Dash looked the same. Can be made to look however specified with proper embossing rolls in manufacture.

 

I agree, they should put some effort into solving the problem. This is America's sports car.

 

My customary contribution to the “3LT dash problem…”

Four points:

1. “Delamination” is a misnomer. The correct term for this type of issue is adhesive failure because that is what causes the problem.

2. Any car with a leather dash can suffer this problem. It’s not exclusive to 3LT Corvettes.

3. Heat doesn’t cause adhesive failure. I realize this is counterintuitive, but heat on a leather dash causes different problems.Cracking, shrinkage, or fading. Sometimes all three.

4. If you are going to suffer adhesive failure with a 3LT, it will likely happen very early into ownership.

I have a 3LT for going on two years and my dash looks like new. I had a 2019 Stingray with a 3LT dash for almost two years and no issue, other than shrinkage around the HUD area caused by heat and fixed under warranty.

As someone mentioned in the thread already, the vast majority of 3LT owners never have this problem. Of course, it sucks when it happens to anyone. When you spend $70k to $100k plus for any car with a leather dash, you expect it not to experience adhesive failure.

 

 

i would ask to see the old parts when you bring it in. We didnt do that so Im not sure what they are doing, but pretty sure its thee same as the original

 

Shame. Looks like the glue could not deal with the cold. Different than the C7 that was mostly shrinkage. The C8 appears to be that type failure. That part is a separate piece so expect they will replace,

 

Jerry, temperature (cold or heat) didn't cause this problem. Adhesive failure isn't caused by temperature cycles. The material is not the problem (yes, I know you are saying that, but this is the erroneous conclusion a lot of people come to). The adhesive is what failed, as you point out.

 

Either the adhesive or the adhesive application process itself...Per GM these pieces are to be replaced not repaired...

 

Any Corvette that I have looked at for purchase had to be a 2LT. Saved a few dollars and headaches.

 

Hmm, adhesives are all different and have various temp ranges. Looked into that when I added lights in my C8 engine compartment.. Checked temps in my engine compartment. The 3M Dual Lock I used is good to 220F.

Some don't do well in cooler temps, quoting:
"Most water-based glues like cross-linking PVAs have a minimum-use temperature (some as high as 60°F)"

Have no idea if it was temp, bad application or like the "Loctite" type product GM used on the side drain plug on my 2017 Grand Sport that required a pipe wrench with pipe extension to remove. Whatever cheap overseas source they used sent some bad product.

Prepared to change the oil at 500 miles on my 2017 Grand Sport. Thought will bring the same 6 sided socket and 1/2 inch drive breaker bar, just in case. The oil cooler is longer in the Grand Sport and very close to the side drain plug. Can't fit a socket and wrench. Tried wrenches in a 12 point box wrench. It was rounding the sides of the soft steel hex! Had the proper metric flare wrench. Still rounding the hex! Fit the 6 point socket on the hex and used a pipe wrench to grip the sides. Worked! Recommend folks but an somewhat unusual 6 sided box wrench. Snap-On sells for ~$40. I found on net cheaper! Drain plug had a brown residue on the treads. Perhaps a cheap "Loctite type" material gone bad or a bad batch bought from the low cost overseas supplier! Crap Happens!

 

@JerryU
I spoke specifically about a leather dash that "bubbles" up or detaches from the dashboard surface, as typically depicted when users complain about (or worry about) the 3LT.

An adhesive failure doesn't require heat or cold to cause a failure. If the adhesive is adequate and doing its job, it won't cause the material to separate and bubble or detach from the dash. I will not argue this point since it has often been discussed here. In this thread alone, an example of an adhesive failure in 42-degree weather was posted. 3LT dashes have experienced adhesive failure in dealership showroom floors and people's garages. This is ample proof that temperature cycling has little to do with adhesive failure.

 

So GM is using the same glue they used on headliners in the 1980s?

 

Interestingly enough the headliner came off in my 2015 C7 coupe but was covered under warranty. Instead of applying some adhesive and reinstalling it they replaced the headliner that comes with the adhesive preinstalled. There wasn't a procedure in the service manual for applying adhesive nor an adhesive specified. This was a relatively common problem as I remember.