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12 Silverado 1500 LTZ
Rocky Ridge package ,,,
Transmission started whining like a power steering pump thats low on fluid then stopped pulling ,,, full of fluid & doesn't smell burnt whatsoever ,,, any ideas on what I'm looking @ for the repair ???
 

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1. You have the 6 speed 6L80e?
2. Just don't have forward gears?
3. Do you have reverse?
4. How many miles?
5. Trans fluid temp when it stopped pulling?

6L80e does not have a forward clutch pack like the 4L60e that will prevent it from getting all forward drive. No brake band to break too.
The 6 speed relies on the TC, 1-2-3-4, 3-5-R and 4-5-6 input clutches and 2-6 holding clutch to get forward gears.
Reverse uses a different set, 3-5-R input clutch and low/reverse holding clutch. If reverse works, TC and pump are good.

So pump fluid pressure is important for the pistons and input clutches to work.
Get it scanned to see if it's electrical and pressure tested if it's mechanical/hydraulic causing your problem.
You can only test the connector for power/ground and CAN hi/lo network signals unlike the 4L60e which is simpler.

But the 6L80e looks like a lot easier to diy in my opinion. I have not rebuilt any yet because my 4L60e still works at 288k miles and 6L80e is fairly new at 30k miles. If it breaks, I'll be too old to diy and won't be able to lift and move it around. LOL
 
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Ahhh crap Bazar, you get a tranny jack and Get R Done! LMAO. seriously though a tranny jack is a must for anyone who is removing a tranny OR a fuel tank, especially one that is full of fuel.

Dude, you know your sh it eh! I'm suprised how different the 6l80E is. I dont know anything about them and really hope I dont ever have to learn anything about them. LMAO.

Al
 
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Al, stick to your 97. Don't buy the new silverados and you'll never have to burn your brain cells learning the 6, 8 or 10 speeds. LOL.
I'm retired, just have nothing else to do to grow more brain cells.

I have a lift, but still will need muscles to handle the tranny.
 
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Al, I think I said it wrong.
I should have said keep your 97, easier to maintain and no AFM and no >4 speed transmission.
 

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NEW gm HAS MANY issues. you should replace the transmission fluid at 40K miles and you must use the correct fluid .. on the 6/8 shifts the GM updated the fluid.
On my 2000 silverado GM said change your fluid at 100K miles .. well I changed it @20k miles.. looked like a mess..
changed the filter and clean up the crap.. I then did it at 40K miles on the truck mileage looks much better .. then when I did the last fluid replacement at 135K miles on the truck looks like new very clean..
 

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J Cat, just to clarify the requirements, the 6 speed uses Drexron VI; however, the 8 speed uses the newer Dexron HP, which has been upgraded to Dexron ULV, which has been upgraded to Dexron LV - HP.

The Dexron VI is backward compatible: however, the fluid for the 8 can only be used in the 8 speeds and the 10 speeds

It is going to be very confussing
 

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I know this is an old thread but I think this is relevant to the original posters issue.
I have observed that my 2018 with the 6L80e is not locking up the torque converter clutch (TCC)as good as the 4L60e.
Whenever I lift the throttle while cruising at say 50-60 mph, as soon as I press the gas, the TCC releases a bit to allow a certain clutch slip which shows as a sudden rpm rise then the TCC completely locks up until you coast again. Then when coasting, I can feel the engine brake whenever it downshifts from 3-2-1 until stopped.
This may be the reason why this transmission do not last as long as the previous 4L transmissions.

The TCC slip contributes to the torque converter clutch lining early failure and the downshifts are too hard on the clutches and planetary gears.

Question:
Anybody knows of a software upgrade or a tuner to remove the TCC slip and the hard downshifts?
 

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Hey Bel, is this something new with your transmission, or something you've noticed from day 1?
I've been driving my 6 speed for 10 years and have not noticed what your describing.
The only time I noticed hard shifting was just before my TPS failed; but I think it was hard up-shifting.
Something in the back of my head makes me think there was a TC change when your generation was built; but I'll need to google to refresh my brain.
Of course there was lots of software changes.
 

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Since new, it's been the same.
It upshifts smooth and has lots of power at 355hp.
The torque converter TCC slip is built into the software and the hard downshifts 3-2-1 bothers me. When it downshifts To 3 rd, the rpm rises and then falls as it slows down then it downshifts again to 2nd and the rpm rises and so forth until stopped.
The 4L60e TCC is locked pretty good while cruising, most of the time when I pass at 70mph, TCC is still locked in 4th gear even when pressing the gas as I don't see the rpm rise as I press the gas and it does not want to downshift unless I really floor it. I think this is a good thing for the TC.
The 4L60e when cruising and you coast, the rpm drops to 1000rpm and does not downshift unless you manually shift to 3rd, 2nd and 1st then you get engine brake.
 

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Hmmmm, mine acts like your description of the 4 speed.
I use to look at the tach while slowing down and think "is this thing ever going to downshift", I'm almost stopped before it downshifts.
If I use the manual downshift I see the RPMs go up, as they should, when I downshift, but no flairs. It must be software.
But sorry, I have no experience with 3rd party tunes.
 

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I think what's happening during the 6L80e downshift engine braking is the Torque converter TCC stays locked from 3-2-1 automatic gear change while slowing down to a stop while shifter is in Drive.

There must be a tuner that will keep the 6L80e TCC unlocked to eliminate the engine braking in Drive. On a steep downhill at Pikes peak in Colorado, to get engine braking, I just manually shift to low gear anyway using the +/- L6 to L1.

But in drive, just coasting to a stop, I don't want the engine braking from 3-2-1 and the TCC locked.
 

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Ok, mine does that, I don't have grade retard; but it will (at least it seems to) keep the TC locked while slowing down. And I don't always have instant power when I give it gas after slowing down; but I always blamed that on the engine torque management.
 

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on my 2016 Toyota truck you have the same issue.. the older vehicles GM on my 2000 silverado I lift the gas pedal and the TCC drops and the engine reduces the speed ..so my brakes work last a long time .. 80K miles pads 60% worn.
my 2016 Toyota you have the same issue .. I have to put it in 4th gear to use engine braking and the brakes on this Toyota looks like 50K miles same wear on my 2000 silverado ...
to get a tuner in today's world probably a hard purchase . Diablo tuner go to the website to change your GM truck PCM software for correct changes you want .
Diablo tuners update on the internet . many like these .
 

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I think I found one tuner that will handle software changes to the 6L80e. HPTuners might be able to do it. I just need to look at what the software can do as far as the 6L80e program is concerned.
 
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I believe the two issues I pointed out with TCC slip where converter will go in and out of lock up even during slight throttle while cruising in 6th gear and engine braking during downshift from 3-2-1 when slowing down to a stop can be addressed by this tuner.
I know the TCC slip and the downshift engine braking will not be good on my 6L80e in the long run so I really need to address this soon.

I plan to get this tuner.
HPTuners.
MPV12, VCM Suite:
Connect > Read > Edit > Write > Drive.

Equipped with enhanced features like Bluetooth®, our Proprietary Expansion Port, and Mobile Device Support, the powerful MPVI2 makes it faster and easier to read, edit, and write your vehicle’s software.

There is a HPTuners Forum on the web too.
 
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