Rear end defining
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
I agree with Dave, its a sterling. The ribs around the perimeter of the case that are cast into the housing is the shape of a sterling, Danas use more of a pimpkin shape. Annother way to check, is to pull an axle shaft, and see what sort of seal there is between the axle flange and the hub. If it has a big O ring, its definately a sterling. There should also be a fill hole on the other side of the pinion housing (passenger side) facing to the front of the truck.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
It depends on weather you have a sterling 10.25, or a sterling 10.5. The 10.25 has 3.33, 3.54, 3.73 and 4.10 (saw 3.33 listed once, but never saw a real one), while 10.5 is only 4.11 and lower ratio (higher numerical).
Since you don't have the stock infor of the truck, the best way to figure your ratio is to pop the cover off, and count the number of teath on the crown gear and the pinion gear.
teath count of crown / teath count of pinion = gear ratio (rounded to two decimal spaces)
Since you don't have the stock infor of the truck, the best way to figure your ratio is to pop the cover off, and count the number of teath on the crown gear and the pinion gear.
teath count of crown / teath count of pinion = gear ratio (rounded to two decimal spaces)
Thread Starter
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Freshman User
Joined: Dec 2007
Posts: 26
Likes: 0
Well from what i have learned from you folks,(thanks for the help) The general concensus is towards a sterling 10.25. I will be pulling the diff cover off on thursday afternoon to get tooth counts? (might need more help then). One other thing i noticed is that top speed is about 55 or 60 ,then it seems to need another gear? So probaly a 4.10 ratio . I have found another 4.10 sterling dually axle, fella says limited slip. So i should probaly have him measure from back plates across to make sure its the same length for a swap??
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
All the 6.9 powered trucks needed annother gear IMO, they were built for a speed limit of 55.
Top speed with my truck was around 70 MPH with 4.10s, at 60 MPH, it was still very loud and only returned 10 MPG average.
3.54 gears would (in theory) put you close to 85 tops.
Top speed with my truck was around 70 MPH with 4.10s, at 60 MPH, it was still very loud and only returned 10 MPG average.
3.54 gears would (in theory) put you close to 85 tops.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Measure from backplate to back plate.
If his axle is out of a dually the spring perches will be in the wrong place.
Dually left the factory with a pickup box and fender flares, 37.5" frame and 3" springs.
Also measure how far apart the spring perches are.
Since you truck is a cab and chassis, one from under a pickup will not fit unless you cut the perches off and weld them back on where they need to be.
Each one would need to move in 1.75".
3.55 gears in a Sterling puts you at 85 MPH at 3300 RPM.
If his axle is out of a dually the spring perches will be in the wrong place.
Dually left the factory with a pickup box and fender flares, 37.5" frame and 3" springs.
Also measure how far apart the spring perches are.
Since you truck is a cab and chassis, one from under a pickup will not fit unless you cut the perches off and weld them back on where they need to be.
Each one would need to move in 1.75".
3.55 gears in a Sterling puts you at 85 MPH at 3300 RPM.
Senior User
Joined: Mar 2007
Posts: 196
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Originally Posted by David85
It depends on weather you have a sterling 10.25, or a sterling 10.5. The 10.25 has 3.33, 3.54, 3.73 and 4.10 (saw 3.33 listed once, but never saw a real one), while 10.5 is only 4.11 and lower ratio (higher numerical).
teath count of crown / teath count of pinion = gear ratio (rounded to two decimal spaces)
teath count of crown / teath count of pinion = gear ratio (rounded to two decimal spaces)
and 3.73, 4.10, 4.30 kits for the 10.5"
I also discovered when talking to them on the phone they had some additional ratios available for some axles that aren't listed on the site, so they may have some additional options not listed for the sterling too.
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Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
Originally Posted by misnomer
I see at differentials.com they list 3.08, 3.55, 3.73, 4.11, 4.56 for the 10.25"
and 3.73, 4.10, 4.30 kits for the 10.5"
I also discovered when talking to them on the phone they had some additional ratios available for some axles that aren't listed on the site, so they may have some additional options not listed for the sterling too.
and 3.73, 4.10, 4.30 kits for the 10.5"
I also discovered when talking to them on the phone they had some additional ratios available for some axles that aren't listed on the site, so they may have some additional options not listed for the sterling too.
.
Post Fiend
Joined: Jan 2000
Posts: 5,330
Likes: 17
From: Dryden, ON, Canada
No 3.08 gears for the D50 or 60... The housings just aren't made to fit those gears.
As for the OP, that's a 10.25 in your truck, and, from the sounds of it, it's from a newer truck. That plastic thing you're using as a fill point is the VSS from an 87+ truck, and the actual fill point is the pipe plug on the side of the pinion.
For your truck, if you are replacing the entire axle, it needs to be from another cab and chassis dually, or if you feel like moving perches and swapping your hubs/drums/backing plates over, a SRW pickup axle will work.
As for the axle itself clunking, have you checked the wheel bearings, and the bolts that hold the axle to the hub. I've had both a failing bearing, and the bolts backing out a tiny bit cause this to happen.
As for the OP, that's a 10.25 in your truck, and, from the sounds of it, it's from a newer truck. That plastic thing you're using as a fill point is the VSS from an 87+ truck, and the actual fill point is the pipe plug on the side of the pinion.
For your truck, if you are replacing the entire axle, it needs to be from another cab and chassis dually, or if you feel like moving perches and swapping your hubs/drums/backing plates over, a SRW pickup axle will work.
As for the axle itself clunking, have you checked the wheel bearings, and the bolts that hold the axle to the hub. I've had both a failing bearing, and the bolts backing out a tiny bit cause this to happen.
