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engine/tranny combinations in 2500HD

tomseeley

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tomseeley Enthusiast

tomseeley

Posted
Posted

Newbie here, so please don't flame for a dumb question!

 

Is it possible to get a 2500HD with the 8.1L engine and NOT the Allison transmission? In other words, if I'm browsing used trucks online and I see one listed as having the 8.1L engine and "automatic" can I assume it's always the Allison or is there a chance it could be a non-Allison automatic transmission with that engine?

BBSilverado Enthusiast

BBSilverado

Posted
Posted
Newbie here, so please don't flame for a dumb question!

 

Is it possible to get a 2500HD with the 8.1L engine and NOT the Allison transmission?  In other words, if I'm browsing used trucks online and I see one listed as having the 8.1L engine and "automatic" can I assume it's always the Allison or is there a chance it could be a non-Allison automatic transmission with that engine?

 

 

 

 

Yes, you can get an 8.1 without the Allison and have an automatic (4L80E)

bluenote Enthusiast

bluenote

Posted
Posted
Yes, you can get an 8.1 without the Allison and have an automatic (4L80E)

 

 

 

Actually, you cannot do this in the pickups. The following are the only combinations that can be had in a 2500HD or 3500 pickup.

 

Vortec 6000 with 5 speed manual

Vortec 6000 with 4 speed auto (4L80e)

Vortec 8100 or Duramax with 6 speed manual

Vortec 8100 or Duramax with 5 speed auto (Allison 1000)

 

The only way you can pair the Vortec 8100 big block with an automatic transmission other than the Allison 1000 is to get a 2500 Surburban or Avalanche....and in that case, the automatic mated to the big block is a 4L85e (same gear ratios as 4L80e, but a few beefier components to handle the higher power).

tomseeley Enthusiast

tomseeley

Posted
  • Author
Posted
BLUE...........You are correct !

 

 

 

 

So, not to beat a horse that's well and truly dead, what bluenote is telling me is that any time I see an online ad for a silverado 2500HD pickup with the 8.1L engine and automatic transmission, I always KNOW it's the Allison?

 

Cool. Thx.

bluenote Enthusiast

bluenote

Posted
Posted
So, not to beat a horse that's well and truly dead, what bluenote is telling me is that any time I see an online ad for a silverado 2500HD pickup with the 8.1L engine and automatic transmission, I always KNOW it's the Allison? 

 

 

Yessir.

Daubs Enthusiast

Daubs

Posted
Posted

Yep, all HD pickups that have the 8.1 are paired with either 6 speed manual or the Allison.

 

You can get the 4L80 with 8.1 in a Suburban though.

Shawn T Enthusiast

Shawn T

Posted
Posted
Newbie here, so please don't flame for a dumb question!

 

Is it possible to get a 2500HD with the 8.1L engine and NOT the Allison transmission?  In other words, if I'm browsing used trucks online and I see one listed as having the 8.1L engine and "automatic" can I assume it's always the Allison or is there a chance it could be a non-Allison automatic transmission with that engine?

 

 

 

 

Yes, you can get an 8.1 without the Allison and have an automatic (4L80E)

 

 

 

 

 

 

Actually BBSilverado the only pickup with the 8100 and an automatic is the Allison. The SUV lineup is available with a detuned version of the 8100 with the 4l80E as you mentioned. I think it is rated at 320 HP. They closed the topic, but do you remember the question the guy had about "what engine he had in his HD"? One jackass replied complaining about how I and some other guys answered his questions. What an ignorant jerk. I wish it wasn't closed so I could chime in on him and make sure we weren't hearing from god all mighthy himself. I hate it when you are trying to help somebody answer a question and you get an arogant person on here that thinks everybody else is below him. Sorry for rambling but I just read his reply and could not answer over there so I had to vent here. I had just seen that you had replied to me on this topic. But anyways, if you have seen the 8.1-4l80E combo in a pickup let me know. Anything is possible.

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