Whats the difference between M814 and M55

[heavychevy]

I am a former 2.5 ton guy myself (sold it wish I didn’t, looking for one), but my brother has a 5 ton. I think it’s a M814, he says it’s a M55. From info that I have found they look the same, so what is the difference?

 

[Recovry4x4]

814 has the NHC250 and the M55 has the R6602. M55A2 has the m ultifuel and the M55A1 has the ENDT673 Mack. . As far as looks, the 814 has the air cleaner on the drivers fender, the 55A1 and 55A2 on the passenger fender. The M55 air cleaner is under the hood.

 

[heavychevy]

His is a gasser.

 

[Recovry4x4]

M55 for sure then. Both share the long wheelbase and 20' bed

 

[heavychevy]

Thanks for the info.

 

[CARNAC]

I thought it was 759.


I know, rather be a smart one than a dumb one.