I need some help.

On ARB's online application chart, it lists the gear ratio for different vehicles. Is this for stock gears or the gears you're going to be using?

Reason I ask is because I have an 04 F-250 that has 3.73 stock gears which would call for the RD35 model, but I'm putting in 4.56 gears which would use the RD36 model. The one I received through a vendor was the RD36.


And on that same note, according to Randy's R&P website, the 10.25 and 10.5 sterling axles don't use the same gears, but when you click on parts for the 10.5 all the part numbers are 10.25 indicating they do switch over. There are also different master install kits but they both show up when you click on the 10.5 axle? And if that's not confusing enough, I bought a Detroit locker from 4wheelparts that was made in 89 and listed for the 10.25, but they said all the 10.25 stuff fits the 10.5.


Here is exactly what I currently have...
ARB RD36 front locker
Detroit 225-SL 56A rear Locker
(Yukon Gear) YG D60R-456R-T #24066 (thick ring & reverse cut D60 front gears)
(Yukon Gear) YK D60-F #14128 master install kit
(Yukon Gear) YG F10.25-456L #24088 rear gearset (long yoke, 93 & newer)
(Yukon Gear) YK F10.25 # 14043 master install kit

Anyone know for sure? I just want to make sure I have all the right parts before it gets torn down.

 

i've been told different stories about the same thing. randy's r&p says that the 10.25 and 10.5 carriers are interchangeable while everyone else i talk to says they're completely different. i think that the guy at randy's told me that the carriers are interchangeable but the ring and pinion sets need to match up with the carriers? i can't quite remember now. i went through this when inquiring about lock rites and they didn't have any for the 10.5 rear end but they had them for the 10.25 so if i changed the carrier, which i was trying to avoid, then i could use a lock rite. i decided if i was going to change the carrier then i might as well get a detroit or arb.

these guys do know everything there is to know about diffs so i would give them a call
http://www.iwerearendsonly.com/

 

There is a split in the carriers for gear ratios. I believe it's 4.10 and down and 4.56 and up, that is unless you use a thick gear. With thick gears you can reuse the numerically lower carrier.

 

10.25" and 10.5" carriers are the same (externally...over the years the OEM ones may be different internally).....same carrier from the 80s to now.

difference is the 10.25" ring gear vs. 10.5" ring gear (of course the pinions are different as are the pinion bearings).
So, to install a 10.25" gear set in a 10.5" housing you just need the right pinion bearings and races and everything installs fine.


I have Precision Gear 10.25" gears and a PG master install kit in my 01 that came with 10.5" gears.....installed them with a buddy of mine with an ARB (did 4.56s and ARB up front too).

As for the case splits.....you can get around them with thick gears as mentioned, which is what most people do.

 

Thanks guys, very helpfull info. I double checked all the part #'s and I have all the right stuff.