I am looking for new gears for my PSD. I run alot on the highway and I dont usually tow more than 5000#, does anyone have any suggestions? Also I would like to find out if my 4.10's are limited slip. And if so, can I get the new gears with limited slip? Thanks for your help.

 

yeah you could go with a higher gear ratio if you dont tow much im not sure whats avalible for the DRW but i would only go up a little like to 3.73's

your limited slip may work with the new gears but would most likely need to be rebuilt and have new clutch plates put in it. or you could go with an aftermarket limited slip or selectable locker.

 

If you look on the drivers door post under the door striker there is a sticker, on there will be a code for the axle,

35=4:10 open
C5=4:10 LS
39=3:55 open
C9=3:55 LS


I just changed the '97 to 3:55's from 4:10's and I really like the quieter engine, my mileage hasn't come up much though, I am still only getting 18's in city/highway driving, when I towed my box home from CO I only got 14 so it wasn't much difference then the 4:10's. I do like the fact that I can now go like 110 MPH and still have some engine left, the 4:10's stopped at about 100.

Just my experience with my gear swap.


on edit, where are you located, I know a realy nice truck place in greeley CO that has just about every axle know to man, I am sure they will have a 3:55 LS if your interested.

Diesel Rod

 

Heck if you want to switch I have 3.73 LS in my 99.5 f-350 I might think about swaping with you

 

i have the 3.73 ls in my 02.... i think it's a good choice for all around use... i don't have any probs towing my 5ver that wieghs 10k, if i'm running below highway speeds, i just shut off the od... but the auto tranny and 3.73 give me around 18 - 20 mpg when i run empty on the highway... once we get off this winter diesel... no doubt my mule would pull more with 410's, but i don't need it, so i'll take the better fuel mileage..

 

I bet he would love the gesture, but the bolt pattern is different on the SD verses the OBS, and I think the frame might be different widths, so you would prolly have to weld on new spring perches.

I am kinda likeing this new idea, have to do some measuring, see if its possible. I also like the idea of rear discs.


Diesel Rod

 

I swapped form 4.10 to 3.55 in my '96 F350 drw and it brought the rpm down from 2400 to @2000 at 100 kph (60 mph). It was quieter in the cab and just felt better. I don't mind revving her up every now and then, but to have to sit at 2700 to do 110 kph just didn't feel right. I don't have the figures, but I know the fuel mileage is up some anyway. I've never had her flatout like Dieselrod, but passing is much easier on the ears and nerves.

 

Well, I just checked my door sticker it says: 45, and after looking in my owners manual this means that it is 4.10's w/o LS. I will be looking into 3.73's w/ LS. I just don't like running all the rpm's on the highway. I don't need 4.10's for towing, I don't ever tow that much. My GCWR is 20000#. I only tow 5000# at any given time. If you know of anyone in SW Georgia that can help me, let me know. Thanks for all the input and keep in touch.