Previously GM trucks required Dexron 6 as approved fluid for their automatic transmissions in gasoline engine equipped vehicles. Due to shudder and failed torque converters in some 2017 Silverados did they change the specification. Its my understanding that the failures were related to the transmission fluid installed at the factory.

 

They almost certainly get their petroleum in huge lots. Perhaps the petroleum distribution company made a mistake.

Years ago f**d was shipping out vehicles, mostly pickups with No gear oil in the axle. Bet that cost them a nice chunk of money.

 

You might be onto something here, I just picked up a 14 and have noticed at a stop in gear I get a odd vibration/shudder.

Maybe I need to get it flushed with the new fluid.

 

Chevy If it were cheaper and give you some peace of mind, then I would do it. Many years ago, I was in the bulk petroleum sales and transportation business, so I know much about how large corporations operate, in particular how a company as large as GM is, with so many vehicles to produce every day, that bulk lots of petroleum would be necessary for smooth operations and brought in by rail-cars full of say, transmission fluid, then transferred into huge tanks located on-site for filling in all those vehicles.

It would be the only logical way to operate such a large corporation, that needs to keep the assembly lines running like clockwork, and make a good profit while putting the proper petroleum products where they belong in each vehicle. In such a large company one would hope they hired the best people to accomplish those tasks.

Most people here don't recommend flushing automatic transmission fluid. There are simply too many horror stories of things going south soon after that is done. Just a simple drop pan and install a new filter, if your vehicle still has the kind of fluid filter that is changed during a normal fluid change along with the transmission fluid should suffice. Since my 2015 Chevy Malibu has an internal filter, it's getting Dex 6 20,000 mile transmission fluid changes. Much cheaper then a rebuild or a new transmission.

 

@Josepj....I found this TSB info that you ought to read. This is for the 8 speed instead of the 6 speed. What was interesting is that they recommended a "different" ATF for problem transmissions. tsb-seems-to-fix-8-speed-automatic-gm-transmission-problems/

 

@hicksvilleshick .....FYI, there'sn easy way to "drain & fill" your transmission since it's the 6 speed GM 6L80 transmission. This transmission still has the "fill tube/ dipstick" under the hood. I just suck the 4-6 qts out of the pan thru this tube & refill with new Dexron VI. Then drive a while, say 500-1000 miles to mix the fluid & clean the transmission & then repeat this procedure. If you're worried about the filter, you can do the messy & time consuming "pan drop". In my opinion, the filter could probably last for "almost" ever. I've removed a filter off our BMW '07 X3 with GM's five & six-speed transmissions and they look very clean after 130k. I'm not sure why everyone wants to change these filters. I personally don't feel they filter the small micron stuff out of the fluid since you see so much of the stuff on the bottom of the pan. Any, that's just my opinion.
1st drain & file will get you at around 40-50% new fluid, the second one makes it about 75% new fluid & so on. onlt takes about 30 mins to an hour & is very simple.

 

Yeah I've heard those stories too, which is why my 220k silverado still has the same fluid in it's trans... But I was meaning more drop the pan and replace fluid vs flush... I used the wrong term.


This sounds like a solid plan I'll prolly do. I have access to a shop and can talk my buddy into hooking me up. As for why everyone wants to change the filters, well thats the old school line of thought. We were always taught that you need to do that and it's just carried over to the newer transmissions, even though it may no longer be necessary. I think I want to do this anyhow because the dealer I just got my truck from (not a gm dealer) did the cooler lines and who knows what fluid they put in.

 

@hicksvilleshick .....I use a simple vacuum pump that I made up that uses compressed air to create a vacuum & I use clear tubing so I can watch the fluid coming out. I pull the tube up when my container gets full; then switch containers (qt. jars). That way I can measure the amount I extract to know how much to put back in. FYI, you can buy 1 gal containers of AC Delco Dexron VI from Amazon at a very good price. The 1st 2 gals I bought were $13.52 each, which is only $3.38/qt. I went back the next day & it was up to $17.50/gal, but still not bad.

 

Niiice. Thanks! I figure if nothing else it won't hurt to run newer fluid in it. I mean I have no issues with the trans at this point, outside of the shudder when stopped, but I've only had it a couple of weeks.

 

Okay folks, here it is right from GM Authority on the new transmission fluid specs:

TSB Seems To Fix 8-Speed Automatic GM Transmission Problems

https://gmauthority.com/blog/2019/08...sion-problems/