2 6l90's toast close to the same mileage?

[supton]

Originally Posted by dave1251
Originally Posted by ls1mike
The beauty is they have a drain plug and the pan is easy to drop.

If you drain the pan you get about 6.5 quarts out. The complete 6L90E system holds 12.4 quarts.
You can do a pan drop and filter swap every 10,000 miles and never have dirty fluid.
Easy Peasy.

I hate to say it, you murdered them.


Mike I have to disagree there was no murder committed. 200K miles is a lifetime for any automatic transmission. Just because it's common for a transmission to go beyond this does not equal it's a expectation.

If a drain and fill is required during every oil change for any transmission this means GM makes dung and does not deserve anyone's business and should close up now.

I'm not sure he's saying that it's needed every other oil change--just that, if one wanted the easy way out, just change half the fluid that often, and it'll simply never be in there long enough to get dirty.

Or one could elect to run to the end of the fluid's lifespan, and then have to do a full oil exchange, which likely is more work (pulling cooler lines, pumping fluid through, etc). More work than a simple pan drop (and still requires a pan drop at that).

 

[nascarnation]

Put some Allison spec TES-295 in your rebuilts and you won't have to worry about any more maintenance.

 

[K20FA5]

Originally Posted by 4WD
Here is my ‘17 6L80e mag at 31k (added plug)


How much of a PITA is that cross pipe to deal with when removing the pan? That's the one thing I'm dreading!

 

[dave1251]

Originally Posted by nascarnation
Put some Allison spec TES-295 in your rebuilts and you won't have to worry about any more maintenance.

That is quite honestly bad advice.

 

[dave1251]

I hope you are correct a drain and fill every 40K should be more than sufficient.

 

[clinebarger]

Originally Posted by Newman88
Originally Posted by spasm3
PM member clinebarger .


Why? Did he have a problem as well or is he going to chew me on the maintenance lol..


The most common issue on the late model 6L80E/6L90E is the TCC clutch lining wears down to the point in goes "Metal to Metal", This metal gets circulated throughout the unit clogging the filter causing reduction in line pressure......The first clutch pack to let go is the 4-5-6 clutch. Delayed engagement, And hard shifts are also symptoms of this failure.

I highly recommend tuning the TCM to eliminate the PWM apply of the Torque Converter Clutch in heavy duty applications, After many hours of data logging these.....The programming allows the TCC to slip on a constant basis. Sure, 17-30 RPM isn't much differential slip but accumulated over 200,000 miles can result in a worn TCC clutch lining!

Interesting fact.....The TCC clutch lining on the 80E & 90E is smaller in diameter than the lowly 300mm 4L60E & quite a bit smaller than a 4L80E.

Here's some pictures of a 6L80E out of a 2015 Silverado 1500 2wd with 150,000 miles that never towed heavy......Not many usable parts were left! Though I was able to save the TCM/Solenoid pack with a good cleaning (Thank you GM for installing filters/screens between the Valve Body & TCM/Solenoids!)
The owner found a 2017 4wd 6L80E on "Offer-up" for $800 & I converted it to 2wd using the old output shaft & extension housing.


1 & 2.....Bottom of the pan....Yikes!!
3...........The Thermostatic Cooler Bypass Valve guts, Yep......The cooler is full of metal!!
4...........Valve Body, More metal.....No sense in opening it up.
5...........Post autopsy corpse.
6...........Burnt 4-5-6 Clutch.....Look at the top of that filter!

 

[Newman88]

Originally Posted by clinebarger
Originally Posted by Newman88
Originally Posted by spasm3
PM member clinebarger .


Why? Did he have a problem as well or is he going to chew me on the maintenance lol..


The most common issue on the late model 6L80E/6L90E is the TCC clutch lining wears down to the point in goes "Metal to Metal", This metal gets circulated throughout the unit clogging the filter causing reduction in line pressure......The first clutch pack to let go is the 4-5-6 clutch. Delayed engagement, And hard shifts are also symptoms of this failure.

I highly recommend tuning the TCM to eliminate the PWM apply of the Torque Converter Clutch in heavy duty applications, After many hours of data logging these.....The programming allows the TCC to slip on a constant basis. Sure, 17-30 RPM isn't much differential slip but accumulated over 200,000 miles can result in a worn TCC clutch lining!

Interesting fact.....The TCC clutch lining on the 80E & 90E is smaller in diameter than the lowly 300mm 4L60E & quite a bit smaller than a 4L80E.

Here's some pictures of a 6L80E out of a 2015 Silverado 1500 2wd with 150,000 miles that never towed heavy......Not many usable parts were left! Though I was able to save the TCM/Solenoid pack with a good cleaning (Thank you GM for installing filters/screens between the Valve Body & TCM/Solenoids!)
The owner found a 2017 4wd 6L80E on "Offer-up" for $800 & I converted it to 2wd using the old output shaft & extension housing.


1 & 2.....Bottom of the pan....Yikes!!
3...........The Thermostatic Cooler Bypass Valve guts, Yep......The cooler is full of metal!!
4...........Valve Body, More metal.....No sense in opening it up.
5...........Post autopsy corpse.
6...........Burnt 4-5-6 Clutch.....Look at the top of that filter!

Thank you sir, this explains and answers alot of my questions.

So in your opinion do you think doing 100k complete trans OCI had contributed in this as well?

 

[clinebarger]

100K is a little long on a unit under commercial use! Though you did a complete exchange which is more than most do.

The unit above had 2 complete fluid exchanges with Delco Dexron VI (50,000 mile intervals) & it still failed. Though the owner (My best friend) drives like crap! Not pedal to the metal hot-rodding.....But on & off the gas constantly. Lot's of in-town driving, Lot's of idle time, Probably similar to what your trucks see from hired hands?

Most of the failures I see are from commercial use, The Isuzu NPR-HD with it's high GVW will chew through them pretty fast.

 

[dave1251]

IYO what can be done to prevent this maintenance wise? I ask this question because I have a 6L80E and it is driven all over the southwest at around a 45K mile clip in 120F heat, up, down, around, mountains, below freezing, fortunately not a lot of idle time and I started fluid changed at around 25K miles and around 47K miles a little more than 100% of the fluid has been changed. My plan was to continue to change the ATF about 4 quarts at a time every 30-40K miles from now on.

 

[BlakeB]

Originally Posted by clinebarger
Originally Posted by Newman88
Originally Posted by spasm3
PM member clinebarger .


Why? Did he have a problem as well or is he going to chew me on the maintenance lol..


The most common issue on the late model 6L80E/6L90E is the TCC clutch lining wears down to the point in goes "Metal to Metal", This metal gets circulated throughout the unit clogging the filter causing reduction in line pressure......The first clutch pack to let go is the 4-5-6 clutch. Delayed engagement, And hard shifts are also symptoms of this failure.

I highly recommend tuning the TCM to eliminate the PWM apply of the Torque Converter Clutch in heavy duty applications, After many hours of data logging these.....The programming allows the TCC to slip on a constant basis. Sure, 17-30 RPM isn't much differential slip but accumulated over 200,000 miles can result in a worn TCC clutch lining!

Interesting fact.....The TCC clutch lining on the 80E & 90E is smaller in diameter than the lowly 300mm 4L60E & quite a bit smaller than a 4L80E.

Here's some pictures of a 6L80E out of a 2015 Silverado 1500 2wd with 150,000 miles that never towed heavy......Not many usable parts were left! Though I was able to save the TCM/Solenoid pack with a good cleaning (Thank you GM for installing filters/screens between the Valve Body & TCM/Solenoids!)
The owner found a 2017 4wd 6L80E on "Offer-up" for $800 & I converted it to 2wd using the old output shaft & extension housing.


1 & 2.....Bottom of the pan....Yikes!!
3...........The Thermostatic Cooler Bypass Valve guts, Yep......The cooler is full of metal!!
4...........Valve Body, More metal.....No sense in opening it up.
5...........Post autopsy corpse.
6...........Burnt 4-5-6 Clutch.....Look at the top of that filter!

Would swapping in an upgraded (triple disc) or at least a new oem replacement torque converter before issues surfaced have saved this trans? If you were aiming to keep one of these units long term, would it be a good idea to throw a new converter in around every 100k miles(assuming you stay with the factory TCM tuning? Did you choose to flush the radiator cooler or replace the radiator on your friends truck? How hot do these units typically run? My Duramax has a thermostat on the trans cooler lines and typically doesn't run much over 140° unless I'm towing heavy, even then it typically stays under 200°F.

 

[Snagglefoot]

Similar situation to Dave1251, except mine is a 6L90 in a 2008 3/4 ton. I'm at 200,000 miles and pull out 3 quarts once per year. Would a preemptive torque converter replacement make sense? Thanks.

 

[clinebarger]

Originally Posted by dave1251
IYO what can be done to prevent this maintenance wise? I ask this question because I have a 6L80E and it is driven all over the southwest at around a 45K mile clip in 120F heat, up, down, around, mountains, below freezing, fortunately not a lot of idle time and I started fluid changed at around 25K miles and around 47K miles a little more than 100% of the fluid has been changed. My plan was to continue to change the ATF about 4 quarts at a time every 30-40K miles from now on.


Originally Posted by BlakeB

Would swapping in an upgraded (triple disc) or at least a new oem replacement torque converter before issues surfaced have saved this trans? If you were aiming to keep one of these units long term, would it be a good idea to throw a new converter in around every 100k miles(assuming you stay with the factory TCM tuning? Did you choose to flush the radiator cooler or replace the radiator on your friends truck? How hot do these units typically run? My Duramax has a thermostat on the trans cooler lines and typically doesn't run much over 140° unless I'm towing heavy, even then it typically stays under 200°F.


Originally Posted by Snagglefoot
Similar situation to Dave1251, except mine is a 6L90 in a 2008 3/4 ton. I'm at 200,000 miles and pull out 3 quarts once per year. Would a preemptive torque converter replacement make sense? Thanks.

BlakeB.......I'm not aware of a Multiple Disc converter that's below 2,200rpm stall for 6L90/6L80 units, I believe the largest billet cover is for a 265mm core. For a heavy duty converter.....You need at least 278mm if not a stock 300mm to get the stall speed right.
The market just isn't there, Stock truck owners & certainly not frugal business owners are ready to drop over a grand. Your welcome to call Circle D in Houston Texas & see if they will build a custom converter!
I replaced the Condenser & Radiator because they were far too contaminated to flush!

Swapping the converter before failure is a good idea! And about the only thing you can do besides tuning the TCM. Of course driving habits greatly influence TCC life span!

Just so I'm clear......You CANNOT eliminate PWM apply/Constant slip function & still keep the AFM active, I've tried it & causes some strange vibrations/power pulses in 4 cylinder mode.

The good thing is.....Low mileage units are still abundant! 2014 & later units can be swapped into earlier vehicles by using the correct Valve Body & Techem(TCM).

Anything over 150,000 & I recommend replacing the Frictions & Steels along with new Checkballs in the valve body as they are plastic & do wear.

 

[dave1251]

Interesting sounds like another GM dud. Well I'll just continue with changing out about 25% of the fluid every 20K miles which is a little less than 6 months for me.

 

[BlakeB]

Originally Posted by clinebarger
Originally Posted by dave1251
IYO what can be done to prevent this maintenance wise? I ask this question because I have a 6L80E and it is driven all over the southwest at around a 45K mile clip in 120F heat, up, down, around, mountains, below freezing, fortunately not a lot of idle time and I started fluid changed at around 25K miles and around 47K miles a little more than 100% of the fluid has been changed. My plan was to continue to change the ATF about 4 quarts at a time every 30-40K miles from now on.


Originally Posted by BlakeB

Would swapping in an upgraded (triple disc) or at least a new oem replacement torque converter before issues surfaced have saved this trans? If you were aiming to keep one of these units long term, would it be a good idea to throw a new converter in around every 100k miles(assuming you stay with the factory TCM tuning? Did you choose to flush the radiator cooler or replace the radiator on your friends truck? How hot do these units typically run? My Duramax has a thermostat on the trans cooler lines and typically doesn't run much over 140° unless I'm towing heavy, even then it typically stays under 200°F.


Originally Posted by Snagglefoot
Similar situation to Dave1251, except mine is a 6L90 in a 2008 3/4 ton. I'm at 200,000 miles and pull out 3 quarts once per year. Would a preemptive torque converter replacement make sense? Thanks.

BlakeB.......I'm not aware of a Multiple Disc converter that's below 2,200rpm stall for 6L90/6L80 units, I believe the largest billet cover is for a 265mm core. For a heavy duty converter.....You need at least 278mm if not a stock 300mm to get the stall speed right.
The market just isn't there, Stock truck owners & certainly not frugal business owners are ready to drop over a grand. Your welcome to call Circle D in Houston Texas & see if they will build a custom converter!
I replaced the Condenser & Radiator because they were far too contaminated to flush!

Swapping the converter before failure is a good idea! And about the only thing you can do besides tuning the TCM. Of course driving habits greatly influence TCC life span!

Just so I'm clear......You CANNOT eliminate PWM apply/Constant slip function & still keep the AFM active, I've tried it & causes some strange vibrations/power pulses in 4 cylinder mode.

The good thing is.....Low mileage units are still abundant! 2014 & later units can be swapped into earlier vehicles by using the correct Valve Body & Techem(TCM).

Anything over 150,000 & I recommend replacing the Frictions & Steels along with new Checkballs in the valve body as they are plastic & do wear.

I just thought of something that my uncle told me several years ago. He was an EMT at the time and said that they had stopped using Chevy Ambulances with the Duramax because they kept losing transmissions in them. I wanna say that those had a 6L90 instead of the Allison. I wonder now if this is the issue that they kept having.

 

[cpayne5]

Originally Posted by BlakeB

I just thought of something that my uncle told me several years ago. He was an EMT at the time and said that they had stopped using Chevy Ambulances with the Duramax because they kept losing transmissions in them. I wanna say that those had a 6L90 instead of the Allison. I wonder now if this is the issue that they kept having.


I don't believe GM backed the Duramaxes with Allisons in the van chassis due to limited space. So, if the ambulances were van body/chassis, then you're probably correct in your assumption.

 

[clinebarger]

Depends on the year, Earlier Duramax vans had a 4L80E which had a issue with blowing through the Direct Clutch. I was one of the first to "Dual Feed" the Direct Clutch during a warranty repair.
The later 6L90E versions would blow though converters & the 4-5-6 clutch

While the Duramax in vans are derated....The torque rise is still quite impressive & hard on transmissions.

 

[Pyrotechnic]

clinebarger,

Do you think that this application would benefit from a spin-on hydraulic filter installed within the cooler circuit? Similar to Allison transmissions that use an external spin-on filter.

 

[clinebarger]

The 6L80E/6L90E's run very clean 'til something comes apart & contaminates the unit. I don't see how auxillary filters would help.

The Allison 1000/2000 spin on filter & magnet protects the Valve Body from debris hence it's name "Control Main Filter", It's not tied to the cooler circuit whatsoever. A transmission has to be designed from the start for this type of arrangement.

Chrysler 545RFE, 68RFE, & related units have a Cooler Circuit spin-on filter from the factory, So.....I really can't dismiss the use of one!

 

[Pyrotechnic]

Originally Posted by clinebarger
The 6L80E/6L90E's run very clean 'til something comes apart & contaminates the unit. I don't see how auxillary filters would help.

The Allison 1000/2000 spin on filter & magnet protects the Valve Body from debris hence it's name "Control Main Filter", It's not tied to the cooler circuit whatsoever. A transmission has to be designed from the start for this type of arrangement.

Chrysler 545RFE, 68RFE, & related units have a Cooler Circuit spin-on filter from the factory, So.....I really can't dismiss the use of one!


One of my friends uses a 6L90E equipped truck for work. Drives around empty most of the time, just tons of mixed city and highway miles every day. Occasionally hauls a heavy load or trailer. What fluid change interval would you recommend?

 

[clinebarger]

50,000 to 60,000