I saw in a post where someone put 373 gears in an 08 F450. Since that person dosen't want private messages has anyone else done this and has it helped with there mileage. I just traded an 08 F350 with the 373 for a 08 F450 that has the 488 in it because I needed to carry more pin weight.

 

I installed 3.73 gears in my F450 and like it. I haul A 3000 pound camper and tow A 7000 pound trailer.

 

You were the one I wanted to contact about this, If your willing I would like to know what's required to do the job. My 373 rear end in my 350 pulls our camper just fine but were short on carring capicity on the back end.

 

I didn't know I can't receave pivate messages, I would change that if I know how. I got the gears for $1200 dollars frnot and rear and installed them my self. the original speed pickup will not work in the rear end with new gears, i machined A spocket to go on the out put shaft of transfer case and made a bracket to hold pickup mounted to trasfer case.

 

i just purchased an 08 f450 with 4.88 gears and i would like to change them to 3.73 or 4.10 what all did you have to do and where did you get your gears?

 

Hey guys I am intrested as well. Would there be a problem pull 24000lbs every once in awhile with 3.73? Also what is the rpms @65mpg? Thanks.

Tex

 

I got the gears from unitrex in Aneheim ca. It would pull 2400 fine just down shift more. With 3;73 gears im turning 1900 RPM @ 65 MPH I was going to go with 2.90 gears, but not all gears are avallible for the front Dana 60. I did the gears myself, other than the extra weight it's an easy rearend to work on.

 

You put 2400 but I'm hoping you meant 24k....I don't pull that often but when I do its heavy. If a hurricane hits the texas or La. Coast I could be in for a long month of pulling 24k lb generators. I do want to drop gears but still need to pull the heavy weight. Right know at 65mph I'm at 2400 rpms! That's got to be killing my mph...what kinda mpg are you getting and are you tuned w a dpf delete? Thanks dude

 

Yes I meant 24000. I get 13 to 14 empty, 9 to 10 with camper and trailer. I was getting 9 empty and 7 pulling trailer with 4.88 gears. I have no tune, maybe when warranty runs out.

 

I understand that Ford has two different rear ends in the 450. Mine didn't have the cover plate on the back and the shop I was talking to could not do the conversion.

I'm getting an avarage of 8.5 pulling 15,000 lbs and 12 to 13 empty with my 4.88. I try to travel between 60 to 65 mph and agree that 65mph is 2500 rpm. My truck happens to be a 4x2 which might make a difference. I can tell you that the 4.88 in my 450 makes a lot more noise than my 350 with 3.73 did because of the difference in the rpm's, both trucks are 08's

 

I'm getting 13~14mpg empty w/ 4.88, a tune, dpf delete, and a afe2...now I'm real curious what I kinda mpg I can achive!

 

When you put those 3.73's in did you have any problems with the abs or anything. Did you have to modify anything!

 

read post #4

 

Considering the kind of work you do I think I'd opt out of the gear change and install something like a Gear Vendors overdrive. That way you still have those deep gears when you need to haul heavy, and the rest of the time you can run the overdrive for lighter loads and/or better mileage. I had one of those (still have it actually) in an old 7.3 and it was the bees knees.

The thing with a gear change is you are stuck with what you get, whereas with the OD unit you can have it all.

 

gear venders aren't cheep, but if you haul alot the low gears are nice to have. I'm only grossing out at 20,000 total rig weight.