Allison Or 4l8oe

[yukon25008.1]

Another quick question does a suburban or yukon xl 2500 have an allison behind the 8.1 like the pickups do, if not why?

[Hulk1999]

GM only put the allison behind 8.1 and DMAX pickups and Meduim Duty Kodiack/Topkicks.

[wtbrowne]

The Allison won't fit into the chassis of the Yukon or Suburb chassis is why not. The 8.1 in the SUV's was detuned to prevent transmission damage to the 4L80e. That's also one reason why the Duramax was never offered in a 1500 series pickup. The smaller diesel being developed for the 1500's has been shelved and may never see the light of day.

[ATMINF]

The 3/4ton burbans had the 4L85E trans in them. As stated eariler the Allys were too big. The 85 have some stronger internals but overall they are a very strong and good trans. As for the 8.1 big blocks being detuned, I am not sure about that. The 4L80 -85 trans are based off of the Turbo 400 trans which were known for there strenght, and we all know the 8.1 big blocks were good, but they were not the strongest motors to be put out by GM.

[gave20]

8.1 was not detuned for a 4L80E, only the D-max.