Sooo, long story short - it's time to upgrade from my GMT400 to a GMT800. i have a VERY specific truck in mind, but I'm not sure i can afford it just yet (or even find one, it's not exactly a common combination).

What I WANT: 2500HD or 3500, 4 door long bed 2wd 8.1l with the Allison trans and black cloth interior.

However - if I can't find one - whats different between an 8.1/Allison truck and a 6.0 truck? Besides maybe front springs, are they the same truck? Can I buy a 6.0 truck to get me by for now, and just buy an 8.1l donor truck later? Are they both semi-floating rears?

Thanks in advance.

 

The rear ends are different.

6.0 uses a 10.5 floater
8.1 uses an 11.5 floater

I wouldnt worry about the color of the interior as much as getting the mechanicals you want.

The HD trucks don't have springs in the front, They use a torsion bar. I am not sure if they use a bar with a different rating or not.

 

OK. I can live with the rear end difference. Worst case it goes boom and then I just put a full floater in it. Interior color is an absolute deal breaker to me though - I'd MUCH rather swap drivetrains than interiors.

Is that the only difference?

 

They're both full floaters but the parts are not interchangeable.

I don't know of the other differences between an 8.1 and a 6.0 chassis

 

Found out the cooling stack and the Air intake are different on the 8.1L Vs. the 6.0L.

The 8.1L has an Allison Vs. the 6.0L having the 4L80E. Not sure if it uses a different crossmember for that or not.

Gm didn't have a true black interior. They call it very dark pewter. It's like a real dark grey color.