Home Forums Gear Hunting Trucks and Four-Wheel Drives 2009 Silverado transmission woes

My brother bought a 2009 Silverado 4x4 a few years back. It had 100k on the odometer, checked the carfax reports and it had been serviced regularly. He runs a construction business so this truck is used as a work truck and not abused beyond what it is spec' d at. A few weeks back he decided to have the transmission fluid changed (approx 140k). He took it to his mechanic who he has known for a while. He dropped the pan, cleaned it out and replaced the filter, when driving home (which is probably 10 miles or so from the mechanic) he noticed the transmission acting up ie ,shifting abruptly, he took it back and the guy added Lucas friction modifier to the fluid. That took care of the issues, although he was concerned that all the old fluid was not replaced.

During Xmas week he took it to the local Chevy Dealer who flushed it , dropped the pan and replaced the filter. Day before yesterday the transmission started slipping on I-95 when he was towing a lightly loaded trailer. Bottomline the transmission is fried and has to be rebuilt. It's on the way to being rebuilt by a local guy and 2500 bucks not cheap . He will not use the local mechanic anymore because he thinks that is what started the ball rolling. I am going to agree with him but not sure if the flushing by the dealer did not contribute as well.

I know of 4 separate Silverado's of that era whose auto trannies were done for at around 100k to 125k. One was privately owned and the other three were fleet vehicles. It's the nature of the beast. IMHO that local mechanic wasn't the cause of your brother's tranny failure.

1500 or 2500?

1500

1500

He said the transmission was perfectly fine before it went to him . That said he didn't even bother confronting either him or the dealer .

The privately owned 1500's tranny had never skipped a beat. One day on the way home from a local shopping trip it started losing gears. Got it home with only third left. The other three 1500's were vehicles my son used at work. Serviced regularly. All three trannies went out in short order. They're not known for being the best. I forgot about a friend who just recently told me her husband had bought a used 1500 Silverado of that era back in April of 2017. Come Sept the trannie was toast. So that makes for five that I personally know of.

Old, high mileage fluid becomes somewhat abrasive with all the fine clutch material particles, and will actually help worn clutches to engage with out slipping. Sooo, what happens to a lot of high mileage transmissions that are serviced for the first time? New fluid, which doesn't have the abrasive particles, does have a fresh additive pack which is more "slippery", results in slippage because the clutches are likely worn and glazed. Not the mechanic's fault. I will not service a transmission in my shop with more than 90k miles on it, if I can't verify previous service at 40-50k miles. I'm not gonna be "that guy".

That makes a lot of sense. I am betting even though the carfax showed regular servicing, betting the transmission was not one of the line items. My brother is not blaming anyone but thinks the first guy put in the wrong fluid even though he only replaced a few quarts. I am guessing it should be good to go for at least 60k or so after the rebuild.

I have a 2017 Tundra my dealer told me to change the transmission fluid at 60k no if's and's or but's.

That's a lot of transmissions failing .

Yes it is.
I have a '96 Cherokee XJ w/~160k miles on it. It has an AW4 auto trans(actually a Toyota trans). It has a drain plug in the pan and no filter per se. There is a wire mesh screen. When the fluid is dirty (changes color) you drain it via the drain plug and add ~4qts.

My old 99 Toyota Avalon had a wire screen as a filter and never one problem...it was tboned at 275K otherwise it would still be running.

Some shops WON'T flush the fluid on a high mileage tranny, just because of this. Additionally, the 4l60E is a known problem. They simply suck, to put it in the nicest words possible.... One of the main reasons I sold my 04 GMC.... You get what you pay for. My best suggestion is to have your brother ask for a heavy duty build. Upgraded servo (corvette), heavy duty clutches (especially the 3-4 clutch pack) and input housing, beast reaction sun shell, plus other options for upgrading. Do your research and make sure your tranny guy knows his chit...

I agree. I had one rebuilt at 111,000 miles by a dealership. That one didn't last long before it was toast as well. They are known problems.

I had our 2010 GMC Acadia transmission fluid changed this last year at 100,000. Then a week later I was listening to one of those car service guru programs on the radio and the guy said not to change it unless it is acting up. It wasn't and it hasn't, but in retrospect I'm wondering if I should have. It wouldn't surprise me to learn that it is the same transmission as the above mentioned Silverado.

No not the same transmission, service manager and I were discussing transmission fluid change on my silverado and he pointed to an Acadia. He said it might be the biggest PITA to replace fluid and change filter ever invented.

I think the guy rebuilding my brothers truck is going to beef it up. He is supposed to be one of the better guys in that area if not state.

I bought a 2004 Silverado used , I had the fluid changed at 60k and before and after that was one of the clunkiest shifting transmissions I have ever owned.

According to this link it sounds like the fluid change in the Arcadia trans (6T75) is done the same way as the AW4 in my Cherokee XJ. At least according to the first 5 posts.

http://www.acadiaforum.net/24-engine-drivetrain/4487-transmission-fluid-change.html

Sounds like how my friend's 03 Silverado's trans was. I've read where you can beef up the 4L80-E to make it a better trans. Hope it works out for your brother. My friend had a Jasper rebuilt trans installed by a certified Jasper dealer and had no more problems. Supposedly Jasper does the upgrades on the rebuilt but not reconditioned 4L80-E trans.

and THIS (the tranny) is the reason I will NEVER buy another GM product... even with following the manufacturers maint recommendations to the T - I replaced EVERY TRANSMISSION of each truck I had at 80-100k until 2000, when I went to TOYOTA.

Strange thing is that my friend traded his 03 Silverado in on a 2014 one. Tried to get him to look at Toyotas and Nissans.