F-250 locking differential

[bsprowl]

I'm tired of my 2000 F-250 having a one wheel drive.  I looked at my door tag and the axle code is blank but I only have a 5.4 engine so I guess the axle is a Ford 10.25. 

Summit has a PowerTrax Right-Lock for a Ford 10.25.  The description says installation can be done with common hand tools so I think I can just take the old spider and and install the PowerTrax - I don't have to worry about ring and pinion clearance if put every back correctly.

How do I tell if my differential is actually a Ford 10.25?

[AlanCasida]

A little word of warning. A friend of mine just recently went through that. He has a 2000 f250 crewcab with the 7.3PS. He pulled his apart only to find the differential in his truck was the 3 pinion design which neither Powertrax or anyone else makes that type of locker for. His was the 10.5. After 2013 all F250s had the 3 pinion differential but I did a little research, and it was possible to get one clear back through 1999.

[pbf777]

      That particular product (and anyone else's) that mounts, that in the fashion of in the O.E.M. case on the pinion cross-pin(s), is really of poor engineering execution from the standpoint of strength.   Aka. it ain't no Detroit Locker!   

      Scott.

[RustyCrankshaft]

You can get TruTrack's for the Sterling axles and I much prefer them over the Powertrax or a clutch type limited slip. Your truck has a 10.5", but for simplicity just about all the aftermarket stuff uses 10.25" stuff so it's backwards compatible.

[AlanCasida]

You can get TruTrack's for the Sterling axles and I much prefer them over the Powertrax or a clutch type limited slip. Your truck has a 10.5", but for simplicity just about all the aftermarket stuff uses 10.25" stuff so it's backwards compatible.

That’s what my friend did. I believe he got the Yukon version of the Truetrac. It ended up being a blessing in disguise since he found worn carrier and pinion bearings that he would not have caught by putting in a Powertraxx unit.

[pbf777]

     On the subject of excessively worn componentry, it seems these units suffer from failures in the sense that the carrier bearings have a habit of turning, both on the inner race to differential snout, but more concerning, of the outer race in the axle housing under the caps; so be sure to inspect for this.   

     Scott.

[TJ]

I'm surprised the truetrac isn't standard in any rear wheel drive street driven and occasional off road vehicle.  Imo, it's more useful than a lot of the geegaws installed as standard equipment.

To bsprowl, I believe a rear stabilizer bar will accentuate the one wheel drive of an open diff.  If not hauling a slide in camper or other tall loads might try it without...if you have one.

[cleandan]

Bob, years ago I fiddled around with various lockers in my 10.25" Sterling differential in my 1990 F250, (7.3LIDI diesel)
From the factory it had 3.55:1 gears with an open style differential and the short style pinion, and about 60,000 miles on the whole thing.
I needed both wheel traction for MN winter driving.

I tried using one of the Powertrax Lock-Right lockers (lunchbox lockers) and it installed really nice, but the first one did not work properly. I was basically a full spool.
Summit was great with the return and sent me another whole unit to try after some discussion proving to them I'm not an idiot and I did not screw things up during installation.

2nd Powertrax, same easy install, but by this time I had researched quite a lot about these things and knew more concerning various clearances.
I installed the 2nd unit only to find incorrect clearances. Everything fit and installed, but things were too tight... but I had all the new parts from the 1st unit too so I started measuring, swapping, fitting, and doing what I could to install this thing to "perfect" specs per the manufacturer.

Installed, measured, verified... driven... still a spool with no differential action under any conditions.
After much trial and error, I was eventually on the phone with one of the engineers at Powertrax.
We spoke about my issues, he agreed I was doing things correctly and saw a video I sent to him regarding clearances and such.
Finally, he admitted that some Lock-Rights just don't work well in certain differentials, with the Sterling 10.25" being one of them... Basically it is a gamble if it will work properly or not.

My next choice was to install a Yukon Grizzly (their version of a Detroit Locker).
That was more than 100,000 miles ago and the only issue I have had is the 3.73:1 gears are a tad howly.
I have changed the lube four times since initial install, with the first two happening after break in miles, then again after a long haul to the East coast and back, otherwise I has been normal maintenance.

I would recommend you get a Yukon Grizzly, install it, and forget it beyond lube changes.
Money well spent in the long run, and you get useful traction all the time.

There are a couple oddities with the Yukon locker.
1) Both rear tires wear a bit quicker than with the open differential due to the skidding around corners more than an open, but the Yukon does allow slipping the majority of the time
2) Both rear tires wear relatively flat across the tread due to the locker too... This makes tire rotation easy to remember each season (I use winter tires and summer tires)
3) Occasionally, under certain conditions, you will experience throttle steer as the locker engages/disengages or stays locked while cornering.
This had only been noticeable when the truck is unloaded, or lightly loaded in the bed only, and while traversing long curved on/off ramps like some highway exchanges use.
There is one I drive many times per week that is basically a long, sweeping curve at highway speed and this is where I experience this anomaly caused by the locker.
4) Sometimes, very rarely, I will hear/feel the differential locking/unlocking in a harsh manner when driving on really slippery winter roads when one rear tire has a lot more traction than the other. Usually when slowing to a stop and an intersection and when one tire is basically on ice and the other having some traction... but this is rare. The clunk, however, will get your attention.

Never have any of these anomalies caused anything even remotely dangerous in terms of driving response and feel. These are just things I notice because I notice these things. I think most people would just drive and never give it a second thought.

Anyway, I have over a hundred thousand daily driver miles with a Yukon Grizzley locker in my 2wheel drive, 3/4 ton truck and I believe it has made my truck better, and safer, to drive year round in Minnesota conditions.

I have heard some rumors that Yukon has changed in quality over the past few years so look into that because mine is pushing 15 years ago that I purchased and installed it.

[bsprowl]

Thanks for all of the replies.  I will check out the Yukon Grizzly. 

[TJ]

Not trying to sell truetracs but am curious why would one choose a detroit locker/grizzly locker over a truetrac.  I think of the lockers as more for dedicated offroad/rock climbing.

You'll never know a truetrac is there (no noise, no weird tire wear, no unlock scenarios), it will last longer than most trucks, and in the odd chance one tire has zero traction you can make your tire that has traction spin by feathering the parking brake...I've done that. 

[jayb]

I like Detroit lockers and pick them because I have lots of experience with them.  Never had issues with tire wear, and only one unlocking issue in 30 years of driving them (in the rain, going too fast around a sweeping curve, minor blip from the rear end).  The new ones are very quiet, and the old ones sound cool in the right car, IMO.  They also "fit" with a 1960s performance vehicle.  I think the disadvantages of Detroit Lockers are WILDLY overstated online.  And Truetracs just don't have the same appeal...

[pbf777]

    Any of the "worm-drive" type units provide a resistance function through a combination of leverage and friction and hence do not necessarily establish "one for one" in rotation for each engaged tire; this vs. the "Detroit" which through direct acting gearing provides absolute "locking" if one tire should attempt a "runaway".   And of these worm-drive units their effectiveness is known to lessen with usage.   

    Scott.

[bsprowl]

The Yukon is more than I want to spend.  And I was hoping to avoid cost of setting the ring and pinion.  The Eaton Truetrac may be what I get.   

[Gregwill16]

Bob, I found a used factory limited slip on eBay for a couple hundred bucks for my 01 SD. Maybe I got lucky it was good, but slapped it in and it served me well.

[TJ]

The Yukon is more than I want to spend.  And I was hoping to avoid cost of setting the ring and pinion.  The Eaton Truetrac may be what I get.

No idea what tires you run on the back but for the money, if you're currently running an all-season then a tire like the Goodyear wrangler duratrac is equal or more valuable than any differential improvement.  In other words, given the choice of an open diff with a proper snow/mud tire or any type of locking rear end with all-season tires, I'd take the open diff with snow/mud tires. 

All-seasons are fine on dry and wet pavement but when it comes to use on wet grass or snow they've helped sell a lot of all wheel drive and 4wd automobiles.   I used to think guys were pulling my leg saying they need 4wd on wet grass until dad got a used pickup that had all seasons...it could barely move on wet grass.  Swapping on some proper rear tires made a world of difference.

In fact, it's probably heresy but my '87 mustang with open differential, snow tires and some weight near the tail lights was way, way, way more capable in snow than any front wheel drive car fitted with all seasons.