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6.6 Duramax in 1500

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Does anyone know if a 6.6 Duramax would fit in a 1500? I have a 2021 3.0 Duramax which actually runs pretty darn good and gets excellent fuel mileage. But I had a 2020 2500HD last year and of course I miss that power.


I'm sure it wouldn't be cost effective by any stretch but I was just curious if anyone knows if it could be done. How much different are the dimensions between the 6.6 and the 6.2?



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I have a 6.2 in my truck.  Not much space to work with.  And, from what I understand diesel engines are heavier.  That might meaning beefing up the front suspension to handle to weight.  What you add in weight you'll lose in payload and towing.  Imo, if GM wanted to make a 1500 HD they'd do it.  They've done it before.  I did the trans fluid and filter on it.  Getting to all the bolts was a PITA at one part of the pan. 

Edited by Transient
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With the right fabrication skills, just about anything can be done.  It would be neat, but require a lot of work and customization.  You'd also need some front suspension upgrades as the Duramax and Allison is quite a bit heavier than the gas motors.  

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Theres a reason the 2500 / 3500 frames are taller - so the motor / Allison can fit.  All previous gen 1500 diesel swaps typically had a body lift in them for the extra space.  But aside from height, the engine bay is the same size from 1500 thru 2500.


And yes - much beefier suspension.  Frame would hold it with some mount modifications.

Edited by FiatDale
Added frame and suspension info
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