2010 Tahoe with 6L80, tune for longevity and towing

[TGMachine]

I have a 2010 Tahoe 5.3 (LMG) with the HD trailering package (8200lb rating) and occasionally tow a 7500lb trailer. It has 170k miles and is currently running and shifting well. I recently purchased an MPVI3 for this vehicle and want to do the following:
-Disable AFM
-Disable flex fuel. I only use regular gas, but I had a problem in the past where the fuel alcohol level got very high for an unknown reason and caused the truck to run rough and required a fuel alcohol reset.
-Make changes to the transmission calibration for longevity. I understand the torque converter is the weak point on these transmission so I've heard many will disable the TCC in gears 1-4 to prevent wear.

When I tow I use the tow/haul mode button. I understand that this will keep the trans out of 6th gear in an effort prevent the torque converter from going in and out of lockup.

My questions:
-Is disabling the TCC lockup in gears 1-4 a good idea for heavy towing? How about disabling slip completely in 5-6 gears?
-Since I use tow/haul mode, does this mean that I'll also need to make the changes to disable TCC lockup in Pattern A?
-Are there any other transmission calibration changes I can make in an effort to get the most life out of my transmission?
-Are there any other good or commonly used changes to the engine calibration that would help in general or with towing and/or longevity?

[Guy With A Chevy]

I blocked the pwm piston in my 4l70e and It seems like that the converter is always free to take an rpm kick but somehow achieves lockup in 4th idk im stumped on that one. I do have a 6l80e tuning out the lockup 1-4 this might be worth buying some more credits

[TransGo Robert]

Can't offer you any help on the tuning side, but would like to warn you to be carreful there. With that much mileage and towing on top of it, the unit is on serious borrowed time. The PR valve has to be worn down to a pencil shape by now. Do not do anything in there while tuning to boost power. Those fuel flex engines do get crazy at time thinking it has high alcohol content, not sure why but a reset always fix them for a long time. Disabling AFM is always a good thing if you don't mind a minor drop in mpg. Disabling lock-up in 1-2-3-4 is indeed very popular, I personally think it does nothing to help the converter last longer, but it does give it a better feel when driving it. When the transmission gives up, be sure to have whoever rebuitlds it put our 6L80E-TOW&PRO in it, it really makes those work sweet for towing and make them last much longer.

[TGMachine]

Can't offer you any help on the tuning side, but would like to warn you to be carreful there. With that much mileage and towing on top of it, the unit is on serious borrowed time. The PR valve has to be worn down to a pencil shape by now. Do not do anything in there while tuning to boost power. Those fuel flex engines do get crazy at time thinking it has high alcohol content, not sure why but a reset always fix them for a long time. Disabling AFM is always a good thing if you don't mind a minor drop in mpg. Disabling lock-up in 1-2-3-4 is indeed very popular, I personally think it does nothing to help the converter last longer, but it does give it a better feel when driving it. When the transmission gives up, be sure to have whoever rebuitlds it put our 6L80E-TOW&PRO in it, it really makes those work sweet for towing and make them last much longer.

Thanks for the info Robert. I'm amazed at the mileage and condition of the transmission and understand it won't last forever... For the first 160k or so miles the truck did not tow anything which has probably helped with the transmission life. I did a filter/fluid change a few months ago and the old fluid was a little dark, but no signs of metal in the pan. I will do another fluid change this summer to help get more of the old fluid out since I'm just dropping the pan and doing about 6 qts at a time.

If none of these trans calibration changes are detrimental to towing I will do them (disable lockup in 1-4, change slip to zero in 5-6). I do not plan on changing any pressures or doing anything to increase power.

When this transmission eventually goes I plan to have it rebuilt with either your tow&pro kit or the zip kit. Not too sure on the differences yet as I've just begun learning about these. Just trying to extend it's life as long as possible before inevitable rebuild.

[Alvin]

I've got 240K on a personal vehicle that I just retired from towing duty. Its held up.

I'd focus on reducing shift times. You can make a big difference just setting target shift times to something reasonable. .35 - .20 second for a upshift is a good range. .35-.15 for a downshift is ok

I'd also avoid letting the TCC slip during cruise.

[TransGo Robert]

Thanks for the info Robert. I'm amazed at the mileage and condition of the transmission and understand it won't last forever... For the first 160k or so miles the truck did not tow anything which has probably helped with the transmission life. I did a filter/fluid change a few months ago and the old fluid was a little dark, but no signs of metal in the pan. I will do another fluid change this summer to help get more of the old fluid out since I'm just dropping the pan and doing about 6 qts at a time.

If none of these trans calibration changes are detrimental to towing I will do them (disable lockup in 1-4, change slip to zero in 5-6). I do not plan on changing any pressures or doing anything to increase power.

When this transmission eventually goes I plan to have it rebuilt with either your tow&pro kit or the zip kit. Not too sure on the differences yet as I've just begun learning about these. Just trying to extend it's life as long as possible before inevitable rebuild.

Got it, I was thinking many it is already amazing it made it that long, towing on top of it this guy must be going to the right church! There is zero comparison between the two kits, our TOW&PRO kit is for towing or performance if you do the tuning part on top of it. Aside from addressing the usual wear issues, it increases drastically the torque capacity of all the friction element. The other kit is simply to addresses wear, it does not increase the towing capacity of the unit at all. As for making it not slip the converter clutch in 5th and 6th that's mostly only good for aftermarket converter that don't use the GM woven carbon lining and so prone to shudder. The carbon woven lining is very brittle and designed to slip without wearing out, but it is super brittle . the extra pressure required to make it not slip and the increase rate of apply is hard on it and it often will crack and lose chunks of it causing the TCC to start slipping after many thousandths of mile with this modification. Eliminating lock up in 1-2-3-4 is not going to hurt anything, but I would not recommend increasing the pressure to stop it from slipping the 20 or so RPM factory programing does.

[TransGo Robert]

I've got 240K on a personal vehicle that I just retired from towing duty. Its held up.

Man that is nothing short of amazing. of course all I ever deal with are the ones that break but it is rare to see any of them make it much past the 100K miles mark. You are definitely going to the right church!

[TGMachine]

Got it, I was thinking many it is already amazing it made it that long, towing on top of it this guy must be going to the right church! There is zero comparison between the two kits, our TOW&PRO kit is for towing or performance if you do the tuning part on top of it. Aside from addressing the usual wear issues, it increases drastically the torque capacity of all the friction element. The other kit is simply to addresses wear, it does not increase the towing capacity of the unit at all. As for making it not slip the converter clutch in 5th and 6th that's mostly only good for aftermarket converter that don't use the GM woven carbon lining and so prone to shudder. The carbon woven lining is very brittle and designed to slip without wearing out, but it is super brittle . the extra pressure required to make it not slip and the increase rate of apply is hard on it and it often will crack and lose chunks of it causing the TCC to start slipping after many thousandths of mile with this modification. Eliminating lock up in 1-2-3-4 is not going to hurt anything, but I would not recommend increasing the pressure to stop it from slipping the 20 or so RPM factory programing does.

That is interesting and the first time I've heard that about the stock converter lining. I would not be changing any set pressures at all, just reducing the desired slip from 20 to zero in 5th-6th gears. So basically you are recommending I don't do any changes to the transmission calibration at all? Neither disabling the TCC lockup in 1-4 or reducing slip to zero in 5-6 are going to help reduce wear on the TCC/trans? Are there ANY trans calibration changes at all that you would recommend for increasing the life of a transmission that has not yet failed? And thank you for the detail on your kit vs. the zip kit, that's very helpful.

[TGMachine]

I've got 240K on a personal vehicle that I just retired from towing duty. Its held up.

I'd focus on reducing shift times. You can make a big difference just setting target shift times to something reasonable. .35 - .20 second for a upshift is a good range. .35-.15 for a downshift is ok

I'd also avoid letting the TCC slip during cruise.

That's great to hear about your high-mileage tow vehicle! I had not considered changing shift times so please bear with me. Is your logic that reducing the shift times would reduce friction material wear due to a shorter time period of slipping during a shift? I don't mind the current (stock) shift timing since this is just a daily driver/tower, but I wouldn't want quicker shifts if they ended up being harder on the transmission.

[Alvin]

Man that is nothing short of amazing. of course all I ever deal with are the ones that break but it is rare to see any of them make it much past the 100K miles mark. You are definitely going to the right church!

I personally got a Chevy SS with a LSA, ported heads, etc.. Its been a while but I think it made 630rwhp. I pulled the headers off it cause I'm sick of driving modded shit since I do it all day at work. and preferred it to be quiet. Anyhoo.. I bought this from a customer that we built it for several years ago. The owner was a travel nurse so its got 192K on it. Still going strong.

I know i don't know everything but it seems like what I'm doing works. hate to come off as boastful.

That's great to hear about your high-mileage tow vehicle! I had not considered changing shift times so please bear with me. Is your logic that reducing the shift times would reduce friction material wear due to a shorter time period of slipping during a shift? I don't mind the current (stock) shift timing since this is just a daily driver/tower, but I wouldn't want quicker shifts if they ended up being harder on the transmission.

Yeah I wouldn't slip a manual to smooth out a shift cause it would be rough on the clutch. Same logic for this. With the times I mentioned with torque management still stock it will have a nice quick shift but nothing rough. It shifts like a car should. Robert offered a interesting counter to my advice to stop converter slipping on the highway. But I haven't seen a bad converter yet. I fixed a lot of "shudder" late trucks with the same method. The local dealers had me even do a few.

[smokeshow]

If you're really looking for longevity, I'm wouldn't toon anything. Maybe add a bigger trans cooler.

[TransGo Robert]

That is interesting and the first time I've heard that about the stock converter lining. I would not be changing any set pressures at all, just reducing the desired slip from 20 to zero in 5th-6th gears. So basically you are recommending I don't do any changes to the transmission calibration at all? Neither disabling the TCC lockup in 1-4 or reducing slip to zero in 5-6 are going to help reduce wear on the TCC/trans? Are there ANY trans calibration changes at all that you would recommend for increasing the life of a transmission that has not yet failed? And thank you for the detail on your kit vs. the zip kit, that's very helpful.

The lining stuff is just not something most people know, same with the fact that the OEM piston has a tapered on it that most aftermarket converter remanufacture can't replicate. When you reduce the slip, you are increasing the pressure, that's how it reduces the slip. With most aftermarket converters that are built with a billet cover, paper lining and many time a pillet piston as well it does not hurt anything to reduce the slip, it actually many time the only way to get those to work well without a shudder. It can handle the shock and pressure no problem.

The OE design converter is a completely different animal. The ling looks like this:
Woven.jpg

As you can see it has a bunch of holes in it, it is not smooth like a normal converter clutch lining. This is so that fluid can always run across it and cool down the lining and the cover it rides against so that nothing gets hurt when it slips a little bit. Now that requires between 25 and 45 psi to maintain 20 RPM of slip while cruising. In order to make it lock completely, you have to crank up the apply pressure quite a bit, usually north of 65 because the lining is just not meant to do that and never makes a perfect seal against the cover. Many tuners bring it much higher than that because the tuners don't know any better not being well verse into the principal of operation and they hydraulics involve.

The other thing most people don't realize is the slip is not an issue at all with that lining. GM has been doing this on all their transmissions since 1996, the lock-up strategy is called ECCC and they all use woven carbon lining with zero issues. This one gets a bad wrap because of the difficulty rebuilding it due to the tapered piston leading to shudder and the fact that the PR valve in the pump wears out prematurally causing unregulated pressure to go in the converter and take it out. So everyone is jumping on the no TCC in 1-2-3-4 and no slip in 5-6 bandwagon trying to fix an non-existing issue aside for the odd feel of it when it locks in lower gears for better fuel economy. That's not what takes the converter clutch out on those, it is the PR valve. We all know an image is worth a thousand words, so here's a couple of pictures that will make it clear that nothing you do in tuning will change the fact that their anodized PR valve loses its coating and gets all chewed up. Our kits addresses that of course. See below:

Here's your typical worn OE PR valve on the left adn a good OE PR valve on the right:
Side by side.png

Here's the worse one I have ever seen, 198K miles on it:
Worse.png

This one had only 75K miles on it:
75K.png

There is sweet nothing you can do programming wise to fix or help that, it's simply a design and material quality issue. Our valves are made of hardened steel and have longer lands that ride in a previously unused areas of the bore to restore the hydraulics and also provide more support to prevent premature wear.

Hope this helps understand a bit better,

[TGMachine]

That's great info, thanks for sharing! So I initially bought the HPTuners device and credits to do AFM disable, Flex fuel disable, and transmission tuning to help reduce torque converter clutch wear and failure. So now it sounds like all I am going to do is AFM disable and flex fuel disable

[TransGo Robert]

That's great info, thanks for sharing! So I initially bought the HPTuners device and credits to do AFM disable, Flex fuel disable, and transmission tuning to help reduce torque converter clutch wear and failure. So now it sounds like all I am going to do is AFM disable and flex fuel disable

You can still cancel lock-up in 1-2-3-4 it will feel better even if it does not help it live longer. But when in Tow Haul mode, it will not command lock-up under load accelerating in 1-2-3-4 anyway I am pretty sure. Also it is not a waste of money because now you have the absolute best and most powerful scanner money can buy, better than the OE scan tool.

[Guy With A Chevy]

Can't offer you any help on the tuning side, but would like to warn you to be carreful there. With that much mileage and towing on top of it, the unit is on serious borrowed time. The PR valve has to be worn down to a pencil shape by now. Do not do anything in there while tuning to boost power. Those fuel flex engines do get crazy at time thinking it has high alcohol content, not sure why but a reset always fix them for a long time. Disabling AFM is always a good thing if you don't mind a minor drop in mpg. Disabling lock-up in 1-2-3-4 is indeed very popular, I personally think it does nothing to help the converter last longer, but it does give it a better feel when driving it. When the transmission gives up, be sure to have whoever rebuitlds it put our 6L80E-TOW&PRO in it, it really makes those work sweet for towing and make them last much longer.

Want to absolutely thank you for sharing that kind of solid information and had no clue you were actually apart of Transgo, good for you man its the only way to go on these things for alot of the gaskets. I am familiar with not wanting to mess with the pressure for a long life span and shear chance of breaking things if/when your mean to it. When you said no lockup for 1-4 it made my ears ring instantly how smoother that would be. I do not plan to tow with it but I am still interested in not experiencing those shift flares.

As for clutches I have rebuilt a few 4l60/70e's and chose borg warner for the 3 i have opened(I just acquired a 4th core for free). Used Exedy one time just didn't like the design/material compared to borg. I encourage every one I try to sell to upgrade all the pistons, corvette servo, sonnax pinless. I do see now that the PR valve upgrade uses the same bore. I have not hand reamed a valve body for a pwm valve sleeve and still looking for a local shop to do it as drilling aluminum has never been my thing, it comes out ugly lol. I am not scared for when this 80k 6L80 might fail but I hope not soon I need to dump money into my older gen iv 6.0

[TransGo Robert]

I do not plan to tow with it but I am still interested in not experiencing those shift flares.

What shift flare are you talking about exactly? Lock-up or not will not cause or fix a shift flare.

[mikez71]

Wow! Thanks for the excellent information Robert! I have linked this thread to tahoeyukon.com forum, hope you do not mind.

Is there anyway to tell just how badly the PR valve maybe worn through datalogging?
I know 6l80 is not expected to live past 100-200k miles, yet there are some instances of them lasting 350-400k miles.

Also do you know what are the causes of the '15-'18 6l80 seemingly not being as reliable as the '07-'14 ?
I do notice some changes in tunes, like the 5,6 gear TCC stays locked all gear, also less slip called for in the upper half of the rpm range in the '15+ vs my 2012..

[TransGo Robert]

Wow! Thanks for the excellent information Robert! I have linked this thread to tahoeyukon.com forum, hope you do not mind.

Is there anyway to tell just how badly the PR valve maybe worn through datalogging?
I know 6l80 is not expected to live past 100-200k miles, yet there are some instances of them lasting 350-400k miles.

Also do you know what are the causes of the '15-'18 6l80 seemingly not being as reliable as the '07-'14 ?
I do notice some changes in tunes, like the 5,6 gear TCC stays locked all gear, also less slip called for in the upper half of the rpm range in the '15+ vs my 2012..

No way at all to tell with data logging, you can tell with a pressure gauge but it takes experience to know what you are looking at and separate what is normal and what is not. I have noticed the opposite pattern, the later ones seem to last longer but that might be more just how it appears then reality. They are in more vehicles in later years that can also affect perception quite a bit. The changes in programing are mostly all done to improve fuel economy and reduce emission, I don't think any of that makes much difference when it comes to durability. As for the difference between some lasting less than 100K and some making it over 200K that's how it is for all transmissions and has always been like that. HOw you driver, where you drive it, the specific model of vehicle it is as well as inconsistency in parts quality always causes that, no way out of it and no reason to make too much of it.

[Pitbull]

I've got 240K on a personal vehicle that I just retired from towing duty. Its held up.

I'd focus on reducing shift times. You can make a big difference just setting target shift times to something reasonable. .35 - .20 second for a upshift is a good range. .35-.15 for a downshift is ok

I'd also avoid letting the TCC slip during cruise.

256,000 on my 2010 yukon denali, drag raced it, pulled all manners of sh!t with it, still trucking. I've probably changed every parameter there is to change at some point.... But I agree getting the time down does wonders. Also no lock up until 5/6 and zero out any slip, increase the apply rate.

[SilveradoWillie]

Could disabling AFM and no TCC lock in 1-4 result in a somewhat less 'dynamic' transmission system result in a less 'active' PR valve potentially reducing wear?

This is great info TransGo. Thank you for sharing. The clutch plate with woven carbon lining definitely seems like it was designed with slip in mind rather than designed to lock