Early build 2019 trans fluid

[madconcept]

I have a 2019 Sierra 5.3 8 speed.

Build date dec 2018.

I’m pretty sure I have the shitty hygroscopic fluid in my transmission.  I’ve experienced a few issues like clunking while coming to a stop and delay then clunk going from reverse to drive.  I also feel at times that truck seems to be slipping in the transmission during a normal to slightly faster than normal acceleration.

The slipping may not be slipping at all and just a normal characteristic of the truck to make it “smoother” perhaps.

 

My truck is going to the dealer bodyshop next week for an unfortunate incident with someone hitting it with their car.  Nothing major but the front bumper needs to be re-painted and left front wheel refinished(small chip).  I’ll have it go to the service dept while it’s there too for an oil change, recalls and the few warranty concerns I have.  I talked to the service advisor for awhile regarding the issues I’m having about the truck.  He looked at TSB’s and said the clunking while coming to a stop has to do with fuel in the tank sloshing around???

My truck also doesn’t fall under the trans fluid flush TSB???WTF? Thought it would?

 

Anyone know what I can do or say to get the fluid flush done under warranty?  Hoping to get the new and improved fluid installed and get that hygroscopic shit out!!

[Jay P]

March 1st 2019 is the cutoff date for the factory fill with new fluid.

MC-10163241-9999.pdf

[Black02Silverado]

It was my understanding that the new fluid was  available Jan of 2019 to all the dealers.  

[wizard4878]

On 3/13/2020 at 7:40 PM, Jay P said:

March 1st 2019 is the cutoff date for the factory fill with new fluid.

MC-10163241-9999.pdf 531.48 kB · 11 downloads

so did the mexico built trucks already have the "good" fluid?

[madconcept]

How do I convince the dealer to flush out the “bad fluid” under warranty?

[Jay P]

2 hours ago, wizard4878 said:

so did the mexico built trucks already have the "good" fluid?

The TSB doesn't say anything about where the truck is assembled only where they are sold. As far as I know the 8L90 is only produced in Toledo, Ohio.

[wizard4878]

44 minutes ago, Jay P said:

The TSB doesn't say anything about where the truck is assembled only where they are sold. As far as I know the 8L90 is only produced in Toledo, Ohio.

just read it again,  my bad,  thought it only applies to trucks built in the US and Canada,  but it says only trucks sold in US and Canada

[Maven]

4 hours ago, madconcept said:

How do I convince the dealer to flush out the “bad fluid” under warranty?

There shouldn't be any convincing required. The current version of the TSB states that no further diagnosis beyond a customer complaint of torque converter shudder is required for vehicles built from start of production until March 1st, 2019.  The issue might be that the dealer is restricted from performing this repair by GM.  If your current dealer wont do it, just ask them what store they suggest you take your service business to.   If they are just trying to blow you off, this will likely get their attention. If they are on restriction, they'll likely recommend a sister store, or another dealer who isn't.

[mbfireboat]

I didn't even have to say anything to my dealer, they did the flush as part of the delivery prep when I bought it last June. Mine was built December 2018 also.

How long has your problem persisted? My transmission acted up suddenly right at 4k miles with the shudder and hard downshift for about three days, and it has not happened again since.

[TBHiker]

Does this apply to the 6 speed as well?

[Garth Hubbard]

I have a 2019 trailboss custom with 5.3 and 6 speed occasionally a violent downshift and approaching a stop how do I know what fluid is in my rear end

[Black02Silverado]

28 minutes ago, Garth Hubbard said:

I have a 2019 trailboss custom with 5.3 and 6 speed occasionally a violent downshift and approaching a stop how do I know what fluid is in my rear end

You would have to look it up by your VIN.

[Garth Hubbard]

where would I be able to look up such information I have my vin handy

[Maven]

This doesn't apply to the 6speed. The 6L80 uses DexVI, not HP.

 

The differentials use 75w85, but 2 different versions.  If you've got GM axles its 19368514 (GM Chassis Group axles have a GM Chiclet logo near the opinion flange or on the bottom of housing )  if you've got AAM axles they use 19300457.

 

axle lube is really unlikely to be causing shift concerns.  

[TBHiker]

11 hours ago, Maven said:

This doesn't apply to the 6speed. The 6L80 uses DexVI, not HP.

 

The differentials use 75w85, but 2 different versions.  If you've got GM axles its 19368514 (GM Chassis Group axles have a GM Chiclet logo near the opinion flange or on the bottom of housing )  if you've got AAM axles they use 19300457.

 

axle lube is really unlikely to be causing shift concerns.  

Thanks for the info on Dex fluid. I'm only at 5k miles so I will monitor awhile longer. Its a slight shuddering over 30mph under very slow acceleration. It might be from switching to 4 cylinders. Not sure.