Detroit Locking differential

Hi Guys,
So after several research and development on google, I managed to find out the Detroit locker are the best to perform as locking differentials.

But I do not know which part is the correct one for my 2012 Expedition?

Someone has written in another expedition forum that Detroit locker rear and Detroit Truetrac front is a powerful combination (the best in fact) for the expedition.

Now what is the gear ratio of my expedition, is it 9.75"? or 8.8"?

I want to order those two, so any website to start with is appreciated and what could be my part number?

Secondly I was going to place an order with Auburn locker, it is similar in functionality to the electronic locking differential in the FX4 package, but I was afraid as I read around some people say it never worked as advertised and fail frequently.

Also the warranty is one year only, it looks short looking to how important is something like this...

Anyone had a previous experience with this subject as a third generation owner?

You can't run an e-locker/Air locker WITH a DetroitLocker.

Eaton (who makes the detroit locker and truetrac) show this:

1997 - 2012 Ford 9.75" Detroit Locker part#225C194A TrueTrac part #913A477

http://www.eaton.com/ecm/groups/public/@pub/@eaton/@per/documents/content/ct_128302.pdf

Your truck probably has 8.8" in the front and 9.75" in the rear; the gear ratios do not matter in terms of installing lockers.

If you can find an application for an e-locker or ARB air locker, that would be the way to go. Both of them are selectable lockers that only lock the axles when you want them to. When driving on the street, the truck drives completely normal. A Detroit locker will bang and chirp the inside tire on tight turns. It's really not ideal for a street driven truck.

In addition, the stability control (and traction control) on your truck may not function correctly. That system needs to be able to send braking to individual wheels to work. If the axles are locked together, it really can't do its job.

one point - the lockers - truetrac and detroit - lock up when under power; I suspect it'd be okay on the streets if you adjusted how you drive. I like to power through corners myself

Another side note - and I cannot over-stress this point: There is no "Best" solution to anything. What you do with your truck dictates what you need. Don't spend money on things that may not provide the performance you are looking for, OR spend money on those things but instead give ME the money and I'll send you the parts you "need" based on your planned useage.

DetroitDarin said:

You can't run an e-locker/Air locker WITH a DetroitLocker.

Eaton (who makes the detroit locker and truetrac) show this:

1997 - 2012 Ford 9.75" Detroit Locker part#225C194A TrueTrac part #913A477

http://www.eaton.com/ecm/groups/public/@pub/@eaton/@per/documents/content/ct_128302.pdf

Your truck probably has 8.8" in the front and 9.75" in the rear; the gear ratios do not matter in terms of installing lockers.

Click to expand...

The problem with ELockers that they perform open differential when not engaged, that doesn't fit my application. Regarding the detroit locker it disengages automatically when turning provided that you be nice with the throttle.

if both wheels are continously turning together as in the detroit locker case, would that harm my mpg?

Sent from my SM-G900F using Tapatalk

tonydiv said:

If you can find an application for an e-locker or ARB air locker, that would be the way to go. Both of them are selectable lockers that only lock the axles when you want them to. When driving on the street, the truck drives completely normal. A Detroit locker will bang and chirp the inside tire on tight turns. It's really not ideal for a street driven truck.

In addition, the stability control (and traction control) on your truck may not function correctly. That system needs to be able to send braking to individual wheels to work. If the axles are locked together, it really can't do its job.

Click to expand...

There is an application for that I think but just the problem is acting as open differential when not engaged. They only and only Locker that performs best as limited slip when not engaged and locked when engaged is the auburn one. But not a good reviews i seen on the web regarding the performance

Sent from my SM-G900F using Tapatalk

The eXpedition said:

if both wheels are continously turning together as in the detroit locker case, would that harm my mpg?

Click to expand...

Not in the least. Your engine wouldn't know it's turning both rear wheels; it turns only the driveshaft.

Maybe do a detroit in the rear and an e-locker up front? Your truck would behave great! Would be more capable than stock having the detroit in the back - and the 4wd system would work exactly the same off-road - except when you REALLY got stuck, you'd engage the locker


Another thing -

Lockers are to get INTO trouble off road. A winch is to get OUT of trouble

DetroitDarin said:

Not in the least. Your engine wouldn't know it's turning both rear wheels; it turns only the driveshaft.

Maybe do a detroit in the rear and an e-locker up front? Your truck would behave great! Would be more capable than stock having the detroit in the back - and the 4wd system would work exactly the same off-road - except when you REALLY got stuck, you'd engage the locker


Another thing -

Lockers are to get INTO trouble off road. A winch is to get OUT of trouble

Click to expand...

You are absolutely right

Sent from my SM-G900F using Tapatalk

I have a Detroit in the rear of a 79 Blazer that I use off road. Off road, the Detroit is awesome and very, very strong. On the road, it really affected the driving quality. Long sweeping turns take a LOT of attention. The power to keep highway speeds on long sweeping turns is quite often enough to make the Detroit lock up. That means the truck is going to try to go in a straight line. So you end up steering more into the turn. Then uf you let up on the gas, the locker releases and the truck has a tendency to dive into the turn.

The biggest issue is a technical one. When under power, the Detroit will allow one tire to free wheel faster than the one being driven. So in a turn, the inside tire is doing the majority of the pushing. With an open diff, the power goes to the wheel that spins the easiest, which would be the outside wheel.

Have fun with your truck, I just recommend trying to drive a vehicle on the road that has a Detroit before you install one-if your truck is a daily driver. I love my Detroit off road. I don't like it on the road. And if there is any ice around, just park it. A locker will definitely require you to need a winch if there is ice around.

I'm glade to have limited slip, now that I here shaky I don't want a locker . its really only good for rock climbing. If you lock the rear in the mud and have to turn you will just sink yourself.
I welded the rear diff on my buggy witch is the same as a locker and my expy goes everywhere it does with the limited slip