46 rears?

All the rear end housings have tags from the factory, otherwise who would know?

 

that's why I was puzzled. take the truck serial # and call a pete dealer. have them run the number to see what it was built with.

 

the gvw will tell the story though.

 

your right but if they are 46 rears it will have the suspension to match as well. normally!

 

Dt 40-170 and dt 46-170 are the same rear ends. Same 3rd member. Dt 40-170 have 7/16"housing thickness at the perches. Dt 46-170 are 1/2" .
Both have 18" ring gears. OEM will put a 40k suspension on the 40 it's one version of super 40s. The other "super 40" is a dsh 40. Which is its own box of weird....15"ring gear with a heavy pinion. The only reason for a dt40-170 is to skirt frame requirements (usually double through the suspension) and more suspension options. You won't see a flex air, ag380, low air leaf, ag 400 or any other 40k suspension with dt46-170. So they came up with dt40-170. If I were to spec a heavy haul truck, it would have a low air leaf or a ag400 L with dt40-170 knowing it would essentially have 46k rears.