GM 6.0/4sp vs. 8.1/Allison vs. 6.0/6sp
Hi all. My Towrig in Sig is getting a little long in the tooth. We just bought a New to us Toyhauler which is quite a bit heavier than our old trailer and my truck is hating life lol!! We were pla...
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I would also take into consideration that the 6L90E transmission has an internal controller (TCM).
Until this application I was not familiar with any component controller that wasn't passively or actively cooled. Your engine ECM likely has cooling fins, your PC has a cooling fan and an OTR tractor has an ECM which is fuel cooled. Processors love a cool environment.
The 6L90E TCM is part of the valve body and lives inside the transmission where it is 160F on a good day.
In 2012 we bought several delivery trucks with the 6.0L engine/6L90E combo, and IMHO the 6L90e does not as age nearly well as the 4L80E.
At about 250K miles the 4L80E will give you a slip code telling you the clutches are getting thin and that it's time for a rebuild.
I have had several 6L90E fail when the TCM engaged an additional solenoid (can you say trans brake?) @ road speed and immediately deposited large pieces of metal into the oil pan.
I believe this controller is compromised in such a hostile environment.
I am not saying that they all fail that soon, only that our 6L90E premature failure rate is much higher than that of the 4L80E and that the damage to the core is much more significant. When it fails it will also require a tow truck, whereas the 4L80e will usually drag it's butt home.
I would go with 4L80E or Allison, both superb choices.
Until this application I was not familiar with any component controller that wasn't passively or actively cooled. Your engine ECM likely has cooling fins, your PC has a cooling fan and an OTR tractor has an ECM which is fuel cooled. Processors love a cool environment.
The 6L90E TCM is part of the valve body and lives inside the transmission where it is 160F on a good day.
In 2012 we bought several delivery trucks with the 6.0L engine/6L90E combo, and IMHO the 6L90e does not as age nearly well as the 4L80E.
At about 250K miles the 4L80E will give you a slip code telling you the clutches are getting thin and that it's time for a rebuild.
I have had several 6L90E fail when the TCM engaged an additional solenoid (can you say trans brake?) @ road speed and immediately deposited large pieces of metal into the oil pan.
I believe this controller is compromised in such a hostile environment.
I am not saying that they all fail that soon, only that our 6L90E premature failure rate is much higher than that of the 4L80E and that the damage to the core is much more significant. When it fails it will also require a tow truck, whereas the 4L80e will usually drag it's butt home.
I would go with 4L80E or Allison, both superb choices.
