How do I know what size my rear differential is? I have an '07 2500 4x4 w/ the 5.9 CTD. I've heard most diesels have a 11.50, but I wanted to know for sure. Thanks

 

Yours has the 11.5. Only some early SO trucks had the 10.5.

 

that information can be found on a sticker attached to the glove box in your pickup. I think it will tell you for the front the rear and gear ratio. its raining outside right now so i wont double check but i'm pretty sure that is where I found out what mine had on it.

 

BJ, they stopped putting those stickers in the glove box sometime between your '04 and my '06.

Titans, as far as size, the '07 diesels all have the 11.5" rear. Now with an auto you could have 3.73:1 gears or 4.10:1 gears. With a manual trans you could only have 3.73:1. Post your RPM's at a given highway speed and I'm sure someone will chime in with what ratio you have.

 

Thanks, everyone. My rpm at 70mph is just under 2000. I think I have 3.73 gears.

 

I have a 2006 2500 5.9 CTD LB QC 4x4 SRW. Does my vehicle have an 11.5 differential?

 

At least one!