I just bought a 2010 SLT Crew (big horn package) 4x2 with 5.7 hemi with factory 20" wheels. Truck has the stock 3.21 rear end and I wanted to now what to do to upgrade to either 3.55 or 3.92. A few questions I have

1. what parts do I need for the upgrade?
2. what is the cost?
3. best place to buy the parts?
4. is this a DIY project?

 

Good news is you have a 4X2, so it's only half as much as a 4X4. If you do a search on this forum there was a couple members who did the swap.They had a detailed list of parts and cost. I would say this much, if you're gonna switch, go with 3.92's.Going just up to 3.55's from 3.22's is not worth the $$$.Good luck

 

another question. how do I know what rear end do I have? is it the 9.25?

 

My opinion due to my own problems (with my Dakota - same differential) getting a good set up and NUMEROUS others expressed on this forum:

FIND A COMPLETE REAR END ASSEMBLY with the gear ratio you want (AXLE HOUSING, DIFFERENTIAL AND AXLES) at a salvage yard and swap out the whole darn mess.

That's what Im going to do as soon as I get time to do the swap myself. It's heavy but not difficult with a jack and a helper.

I'm going to a 3.92 on my Ram because of hilly terrain where I live and mountain towing on road trips.

OEM gear set and installation at a Dodge dealer is going to cost about $1,500 to $2,000.

A used rear assembly can be had for about $700 to $1,000 and any shade tree mech can do the swap. Not so on a ring & pinion set up.

 

problem with that is how do you know the gear ration on the rear end from the junk yard? also call me stupid but I have issues with putting a junk yard part on my brand new truck.

 

Good question and good precaution.

I have a working relationship with 3 salvage yards that I trust so for me its a no brainer but I understand your reluctance.

That being the case, do a lot of research to find a good set up man.

 

Was there no trucks with the 3.92 available when you bought yours? I bought mine 15 months ago and they all had 3.21 or 3.92. Only the Sports had the 3.55. I think the upgrade cost for the 3.92 LSD was around $200.

 

If you're asking me. No. End of year discounts on '09's persuaded me to buy one off the lot and pickings were few with the other equip I wanted.

 

this is my first truck (kia spectra before this) so i really didn't know anything about the rear end gears. had I know what I know now I would still have bought the truck because I got such a good deal on it. if I need to spend a few hundred buck to get it where I want it i'm ok with that.

 

4.10 with those big tires, it actually will help ur mileage, it did me dont bother w 3.55 not a big enough difference.