sterling 10.25???

[blazinchuck]

so can anyone tell me what this is? would this be a stock posi unit? kinda look like this detroit i found, but it doesnt work like a locker...it works like a open rearend




here is the detroit from Randy's
http://www.ringpinion.com/ProductDet...spx?ProdID=227



currious if this can be welded also?

[cslimfu]

looks like my detroit.

[blazinchuck]

Originally Posted by cslimfu

looks like my detroit.

well, i guess you wouldnt have any pics of what yours looked like eh? the problem is, this is acting like an open rear-which sux!

[FF3PM]

x2 that is a detroit locker. You can see in your middle pic a little bit of a yellow coil spring inside. The factory LSD (trac-loc) you would see a side gear, no spring.
Yours might be broken or jammed up, not unheard of.
Photo1 Sterling Detroit locker
Photo2 Sterling 10.5 trac-loc
Photo3 Sterling 10.25 trac-loc.

[blazinchuck]

thank you, i will pull it and see whats up

[Ak_F250]

When you say it doesn't seem to be working like a detroit, do you mean while driving or messing with it on jackstands?

Ive worked on several rigs (mine included) with detroits that would unlock and freewheel if you spun a tire by hand.

[blazinchuck]

Originally Posted by Ak_F250

When you say it doesn't seem to be working like a detroit, do you mean while driving or messing with it on jackstands?

Ive worked on several rigs (mine included) with detroits that would unlock and freewheel if you spun a tire by hand.

so far, i havent driving around with it yet. but when i was rolling the axle from the yard to the garage(it had 38's mounted on it) it was going everywhere. i would push the left side and the right would roll back toward me, and visa versa. now that its under the bronco, i can jack the rear up and one tire turning forward the other rolls back. i wondered also, if it was because i have no power driven to it-maybe thats why its unlocked? thanks for the replies guys

[FF3PM]

It was a very good time for you to ask. I have been trying to find a pic of a sterling detroit locker for a week or so and found nothing. I just bought this one and was installing it yesterday so I took some pics as I was working on it.
I thought yours was acting up while driving. I would wait to see how it acts when under power.

[blazinchuck]

Originally Posted by FF3PM

It was a very good time for you to ask. I have been trying to find a pic of a sterling detroit locker for a week or so and found nothing. I just bought this one and was installing it yesterday so I took some pics as I was working on it.
I thought yours was acting up while driving. I would wait to see how it acts when under power.

thanks again

just talked with Eaton...no way for this to work the way i was thinking. detroit will not allow one tire to turn forward and the other to turn opposite. it can only be broken side gears,springs,etc....but in that case, one tire just wont turn.

i just jacked up one side of the axle...and yes one tire will turn with some soft clicking. i can jack the whole axle and make both lock and unlock. so it looks like its working, it may need a overhaul...side gears might be worn some. but, wow...what a bonus to find in a axle, 1 week before i hit the wheeling trip!!!!

[chrisevans2645]

Originally Posted by FF3PM

x2 that is a detroit locker. You can see in your middle pic a little bit of a yellow coil spring inside. The factory LSD (trac-loc) you would see a side gear, no spring.
Yours might be broken or jammed up, not unheard of.
.

wait a minute, mine looks like the bottom one and i thought it was open. i haven't run additive in it or anything but then i was changing the gear oil in it and noticed what looked like clutch packs behind the spider gear. i took it to my mechanic who specializes in rear ends and put it on jack stands and tested it. he agreed that what i have is a limited slip, albeit slightly worn out. could this be aftermarket because it looks like the bottom pic, not the middle.

[cslimfu]

could be a LSD compaired to a power lock.

[TroyM]

i think you have to have power to the pinion gear for the diff to lock. no power to the pinion and it unlocks around a corner. or am i wrong?

[82F100SWB]

There are 2 different factory limited slips, the 97 and older one looks like an open carrier but has clutch packs hiding behind the side gears, the closed unit pictured is out of a 10.50.

[chrisevans2645]

Originally Posted by 82F100SWB

There are 2 different factory limited slips, the 97 and older one looks like an open carrier but has clutch packs hiding behind the side gears, the closed unit pictured is out of a 10.50.

that explains it. i've got an arb that's going in there monday if the parts come in time. i'm interested to see how much of a difference it will make

[FF3PM]

chrisevans2645- thanks for pointing out my mistake, the third pic is indeed a 10.25 trac-loc, see the clutch pack clips in the opening. The 10.25 trac-loc only has two spider gears, the 10.5 has three, and uses a split case that is bolted together like the middle photo shows. Both use the same clutches behind the side gear design, but different clutch part numbers due to the 2 v/s 3 spider design. Because the 10.25 only has 2 spider gears the inspection window in the carrier is larger compared to the 10.5 pictured. The one piece case in the third pic is possible because of only one spider gear shaft that can slide out. The 10.5 has three spider gears so they are not on one straight shaft requiring a split case design.

[dmsFab]

Dumb question but what year did Ford start using Sterlings? What rear is this? D80 or??? Looked and looked and I cannot find a BOMor anything on it. I havent searched a huge amount. It's in a 97 350 PSD single wheel. It's not a 70, the cover is a good 2" bigger then a 70 cover.

[Mr. Death]

Thats a sterling 10.25. Ford started using them in 83. Easiest way to tell a sterling is those gussets around the diff, and that the fill plug isnt on the cover.

[chrisevans2645]

a dana 80 has a cover that is narrower also

[FF3PM]

Just a little more ID info. The Sterlings use 12 cover bolts. All Dana axles from D25-D80 use 10 bolt covers. Sterling 10.25 has drum brakes and mount the shocks in front of the axle tube. The 10.5 mounts the shocks behind the axle tube, and use disc brakes*. BOM# are a Dana/Spicer axle thing, Sterling is made by Visteon and originally by Ford so they do not have the BOM stamped on the tube like a Dana. Speaking of axle tubes they are 1/2" thick, 3 1/2" OD. The ABS tone ring has 120 teeth. Ring gear bolts are a known "weak" area due to lack of a shoulder where they pass through the carrier. I believe GM Corporate 14 ring gear bolts are a upgrade because they have a shoulder. There are no carrier breaks in Sterlings, carriers and gears are interchangeable between the two models, but I do not know for sure on the semi float axles as I do not mess with them.
*There is an exception in early 1999, the shocks were mounted one in front and one behind. Also early 99 used different calipers as later years, they are the same part for left and right due to one side being mounted in front of the tube and the other behind the tube. Later years mounted both calipers behind the tubes and have different part numbers for left and for the right.
I edited post #15 as I made a mistake describing the cases and labeling the pics.

[dmsFab]

Thanks guys. That is some good tech FF3PM. This rear(the whole truck) has 317,xxx miles and hearng that the ring gear bolts are a weak spot, I think I will pull the cover and have a look-see. I think I'll do that tommorrow. Now I am nervous!

How likely is it for the rear to have an lsd? Some times it acts like a lsd and some times it acts open too. I figure if it has an lsd then it is well worn.

[blazinchuck]

i was able to test drive to bronco, and all seems good. i huess once i apply power, she's locked.thanks for all the help

[FF3PM]

dmsFab I will say the chances of it having a trac-loc is better than 50/50. Most that I have seen have been LSD, but I have only worked on diesel application axles no gassers. All the diesel DRW Sterling 10.5 axles I have seen were LSD 4.10 gears.
From Ford on 1994.5 on up in either 10.25 or 10.5, USA market the full float axle came with these gear ratios; in both LSD or open. The LSD was a very common option. 3.55, 3.73, 4.10 were the ratios offered in a diesel, the others were for gas engine applications. There are other ratios in the aftermarket.
3.55
3.73
4.10
4.30
4.56
There are of course exceptions to every rule. I know Utility companies could order odd combinations.
Ring bolts- they are not weak, or known to break. The issue IIRC is there is no shoulder, so if they come loose or the ring ring gear slips the threaded part will bang around in the bolt hole of the carrier. The threads having much less contact surface area will get beat up and undersized allowing for more play. Most people will never have any issue.
blazinchuck glad yours is working.

[82F100SWB]

Ford did not offer the full float 10.25 with 3.73's, The HD trucks were 3.55/4.10 only. Only the semi floater got the 3.73 option. 99+ on the 10.50 in the Super Duties, 3.73 is most common, with 4.10's and 4.30's also being avalable.
There are factory 7.17's out there, but they might as well not exist.

[FF3PM]

I was not saying the 3.73 was offered in a 10.25, rather that it has been offered by Ford in a sterling full float wether it be 10.25 or 10.5. I edited to make this more clear. Prior to 94.5 I really have not worked on but one or two. The older the truck the more scarce it is in the rust belt.
What HD trucks are you talking about? Do you mean OBS? since they had 3.55 or 4.10 gears offered.
Not trying to argue just trying to learn as I do not work on gas engines or many light duty trucks, which is why I know nothing about the semi-float version.

[dmsFab]

Cool, thanks for the info. That is some good stuff to know. I didnt get a chance to pull the cover today. As soon as I do, I will see what is has for a carrier/lsd. I know it is 4.10's since I had to do inner seals in the front last summer, which sucks because I needed to to front ujoints too and didnt. Now the seals are starting to leak again.