Transmission Tuning

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L8T BURB

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Hello all! I wanted to hopefully spark some conversation here with prolonging transmission/torque converter life span and whether tuning should be equally recommended alongside the thermal bypass upgrade.

I know that high temps seem to expedite the process of these transmissions failing...so of course the thought is to replace the thermostat with the updated GM one, adding external cooler, flipping the pill, or installing the sure cool kit to allow full fluid flow.

During my L8T and 6L90 swap into my 2015 Suburban, my tuner recommended a transmission tune to disable TCC slippage in all gears, and also disabled TCC lockup in all gears except 5th and 6th. This transmission tune was done remotely and only cost me $150.

I guess my main question is, should we be recommending people to do this tune alongside the trans thermostat upgrade? I am by no means a transmission guy, or even a transmission novice....so let's get that out of the way lol. My thought is that the tune along with the thermostat would be good not only as preventative maintenance on an existing transmission, but also on any transmission replacements. Additionally, I plan to drop my pan and replace the filter once a year. Excessive? Of course...but seems like a small price to pay for what may keep this thing from exploding again.

Thoughts??
 

Marky Dissod

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high temps seem to expedite the process of these transmissions failing ...
True. The other thing that does these powertrains no favors is Cylinder Confusion, which your L8T avoids by design (lucky bastaducci).
One of the reasons for the TCC slippage GM programmed in is to mask Cylinder Confusion transitions.
The other is likely general NVH concerns that GM has about 'light-duty' customers ...
... but not the other customers who understand that they're buying a truck instead of a car ...
... main question is, should we be recommending people to do this tune alongside the trans thermostat upgrade? ...
... My thought is that the tune along with the thermostat would be good not only as preventative maintenance on an existing transmission, but also on any transmission replacements.
YES, gottdamnt, YES!
YES, GM tuned most 6L80Es prioritizing two criteria specifically at the expense of longevity & durability:
avoiding NVH complaints from Karens and other light-duty type customers
appeasing CAFE by using the minimum line pressures needed to maximize MpG scores

In other words:
if shifts were a tad less gentle (only just a tad)
if TCC applications / releases were a bit more positive
if most 6L80Es were tuned more like the 6L90Es in 2500HD / 3500HD trucks

They might get 1 or 2MpG less, but they'd also last longer.
Additionally, I plan to drop my pan and replace the filter once a year.
Excessive? Of course ... but seems like a small price to pay for what may keep this thing from exploding again.
When you bought the L8T, and had it installed, did you bother to get an owners manual, or any other relevant info, from vehicles in which the L8T originally came in?
I'd not be surprised if the 2500HD / 3500HD trucks' owner's manuals have very different service intervals from lighter-duty Silvierrados.

Also, once a year seems far too imprecise. It should be based on how many miles, as well as the type of miles.
If it never tows and is driven gingerly, it need not change ATF nearly as often as the one that often tows very heavy uphill.

I say, go by one of the manual's more 'severe service'-type intervals.
 

NickTransmissions

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Hello all! I wanted to hopefully spark some conversation here with prolonging transmission/torque converter life span and whether tuning should be equally recommended alongside the thermal bypass upgrade.

I know that high temps seem to expedite the process of these transmissions failing...so of course the thought is to replace the thermostat with the updated GM one, adding external cooler, flipping the pill, or installing the sure cool kit to allow full fluid flow.

During my L8T and 6L90 swap into my 2015 Suburban, my tuner recommended a transmission tune to disable TCC slippage in all gears, and also disabled TCC lockup in all gears except 5th and 6th. This transmission tune was done remotely and only cost me $150.

I guess my main question is, should we be recommending people to do this tune alongside the trans thermostat upgrade? I am by no means a transmission guy, or even a transmission novice....so let's get that out of the way lol. My thought is that the tune along with the thermostat would be good not only as preventative maintenance on an existing transmission, but also on any transmission replacements. Additionally, I plan to drop my pan and replace the filter once a year. Excessive? Of course...but seems like a small price to pay for what may keep this thing from exploding again.

Thoughts??
Many of my 6L customers turn off TCC apply in gears 2-4. Keeps the workload lighter on that POS converter. That coupled with deleting that dumb TBV helps alot.

You dont need to replace the filter that frequently; once every 40-50k is fine. If you really want to help the converter last, drop the valve body and install a Sonnax zip kit or Transgo Reprogramming kit for the 6L80. Those kits address a lot of issues
that stem from valve body and separator plate wear. That coupled with a thv delete and good tune will ensure longevity for the trans.
 

man n black

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The short to your question is YES...rationale is solid.

My real world example is the 68RFE in my RAM 2500 CTD.

When first introduced they were notoriously unreliable. Mine was tuned (as was the engine) from 1300 miles and we added a deeper finned aluminium sump / pan. Have had absolutely ZERO problems with it even though we towed a heavy trailer all over the USA and Canada high mountains (even steep, from dead stops at high ambient temps - 100 deg Donner Summit) for roughly 65K miles. My only gripe about the tuning is the coverter lockup strategy. The tranny tune in my truck locks the converter in 3rd-6th and there were times, particularly when towing in less than ideal weather or offroading where it would be very beneficial to have TC lockup in second gear as well. First gear lockup is just very tough on internal transmission components.

I would make a few changes to your converter strategy. Instead of disabling coverter lockup in lower gears I would enable it in all BUT first gear. It may sound silly but this actually improves thermal gain and clutch pack life since the transmission is not allowed to 'Slip' the clutch pack when the converter is locked.

Ch
 

MobileHomie

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Just how does a person go about their transmission tuned?
Does the TCM need to be removed and shipped to the tuner?
 

Marky Dissod

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The less disgusting way to do it is to drive to a tuner near you.
That way your ecm gets tuned at the same time.
 

Doubeleive

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Just how does a person go about their transmission tuned?
Does the TCM need to be removed and shipped to the tuner?
It's usually done with a tuner thru the OBD port.
idealy you want it built with all the fixes and a billet torque converter, then tuned.
 

Jonmurphy

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Hello all! I wanted to hopefully spark some conversation here with prolonging transmission/torque converter life span and whether tuning should be equally recommended alongside the thermal bypass upgrade.

I know that high temps seem to expedite the process of these transmissions failing...so of course the thought is to replace the thermostat with the updated GM one, adding external cooler, flipping the pill, or installing the sure cool kit to allow full fluid flow.

During my L8T and 6L90 swap into my 2015 Suburban, my tuner recommended a transmission tune to disable TCC slippage in all gears, and also disabled TCC lockup in all gears except 5th and 6th. This transmission tune was done remotely and only cost me $150.

I guess my main question is, should we be recommending people to do this tune alongside the trans thermostat upgrade? I am by no means a transmission guy, or even a transmission novice....so let's get that out of the way lol. My thought is that the tune along with the thermostat would be good not only as preventative maintenance on an existing transmission, but also on any transmission replacements. Additionally, I plan to drop my pan and replace the filter once a year. Excessive? Of course...but seems like a small price to pay for what may keep this thing from exploding again.

Thoughts??
As I just said in another post The best way to keep your transmission fluid Add 2 car oil filter cartridges, In parallel Not series What happens then? the mobile oil filter Filters about 10 microns, When you cut the flow in half You cut the pressure in half so now the filter Filters much finer about 5 microns.
You need to keep your transmission Cooler than recommended I recommend about 200° maximum. Gauges are cheap. If you add a cooler You can mount it under the car you don't have to put it up in front of the radiator Under your vehicle It's fine There is a lot of turbulence air under there,Just be sure your cooler has larger lines than The stock Cause you don't want any restrictions. Murphy's law
 

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