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Discussion Starter #1
I am looking for information on these rear ends and hoping someone may know the answer to my questions.

1) Is there a Limited Slip option available for these trucks? I just bought a 2013 XLT 4x4 Supercab and when I was buying my truck, all the trucks at the dealership only had the Electric Locker. Okay for Off-Road or snow, but not the street.

2) I have the Electric Locker, but it is only good to 25 mph. Is there a kit which will allow you to override it to a higher speed? And is there a problem if you did lock it to work at higher than 25 mph if off-road or in snow?

3) How good are these rear ends or should a person conside swapping it out for an after-market unit?

4) How big is the rear? I saw some where 9.25" and another saying 9.75". Usually the bigger the better, but is it better than the venerable Ford 9"?

Thanks in advance for all your responses.
 

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Return question: why would you want to lock the rear axle at higher speeds? Traction control should be more than adequate once the wheels are spinning that fast.

Incidentally, i had the traction control come on at 60mph on the highway. Stuck behind someone trying to decide "is this my exit?" and slowing down to 40, put my foot into it to lane change and pass. Just as I was going past him, engine shifted (i think from 2nd to 3rd) and the truck shuddered for a moment, and I looked down to the dash to see the TC light flashing at me. More than a little impressive.

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I am looking for information on these rear ends and hoping someone may know the answer to my questions.

1) Is there a Limited Slip option available for these trucks? I just bought a 2013 XLT 4x4 Supercab and when I was buying my truck, all the trucks at the dealership only had the Electric Locker. Okay for Off-Road or snow, but not the street.

2) I have the Electric Locker, but it is only good to 25 mph. Is there a kit which will allow you to override it to a higher speed? And is there a problem if you did lock it to work at higher than 25 mph if off-road or in snow?

3) How good are these rear ends or should a person conside swapping it out for an after-market unit?

4) How big is the rear? I saw some where 9.25" and another saying 9.75". Usually the bigger the better, but is it better than the venerable Ford 9"?

Thanks in advance for all your responses.
i posted this in another thread where you asked questions like this...

"The ford 9 in hasnt been available or manufactured since 1986!!! The 9.75 is plenty strong...the 9in would almost be a downgrade... you would have to put a lot of money into a 9in to make it live reliably in trucks of this weight..... the 9.75 is much more up to the task..bearings are much larger and pinion stem much beefier....

And the 6r80 trans is one of the strongest trannies made today.....itll put up with whatever 95% of us guys will put in front of it....it has a ton of clutch, all hard parts are GROB, which has amazing heat dissipation properties...and uses variable force solenoids which can exert a ton of line pressure adjustable via a few key strokes from a tuning device..."

theres no reason to lock the rear after 25!! if you do the truck may feel funny at highway speeds...and may scare you if a sudden lane change has to happen....

it is a 9.75 rear

lightning trucks are breaking 8s in the 1/4 using this rear....no need for upgrades here.
 

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to give more of a reply yes there is a limited slip option from Ford but i dont know what is involved with trying to convert it from the E-locker to limited slip because these rears are too new to me yet.
it is more than likely just a change of a few internal parts.
there is a limited slip option for the 3.55 and 3.73 rears
a knowledgable service dept may be able to answer that question and provide prices.
i also have a 2013 with E-lock rear and was looking for the limited slip option but i cannot find any thing bad to say about the E-lock yet.
you would never want the E-lock engaged after 25mph or it would put you into a spin cornering because it does not differentiate between wheels at all.
 

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there are also a few aftermarket limited slip and posi carriers available for the rears if you decided to go that route.


Hook up with Auburn Gear High Performance series differentials and outperform the competition! These differentials deliver superior performance through a unique cone-clutch design that transfers more power to the high-traction wheel for quick acceleration and tight cornering. The Auburn High Performance limited-slip series is engineered to provide smooth torque-sensing operation with the correct bias ratios to meet your performance needs--whether they involve daily driving or muddy back roads. Plus, every gear unit is inspected and hand-assembled in America. No matter what you're driving, Auburn Gear High Performance series differentials will maximize your vehicle's traction for optimum performance.

units like these range from $400-$600
 

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most reliable option here would be a detroit true-trac....very reliable and dont wear out (worm gears)...smooth torque transition etc...

the auburns use a non rebuildable cone clutch and most guys find doesnt work effectivly after a few years of use..

the ford factory traction-lok uses plate style clutches and bellville springs...its ok but seems to wear and become less effective after a few years...ive rebuilt a tone of these!!! usually they begin to shudder...
 

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True, i guess it all comes down to what you want to spend in the end
i honostly dont even know if detroit has a locker available for the 9.75" rear or what their price range would be
 

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True, i guess it all comes down to what you want to spend in the end
i honostly dont even know if detroit has a locker available for the 9.75" rear or what their price range would be
they do have a locker available....but they aren't the most quiet or comfortable diffs....I run one in my lightning and my ranger....sometimes they surprise ya...not smooth by any means..but get the job done...
 

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Discussion Starter #9
The reason I am enquiring about a Limited Slip is for off the line performance on dry road as well as off road. Traction Control is fine if something happens on a slippery road you weren't expecting. But for "off-the-line" performance (aka drag race), Traction Control hurts performance and I would prefer to turn it off. This is where Limited Slip would be better.

As well, from I have read, you do not want to use the Electronic Locker on dry pavement (just like you wouldn't want to use 4x4).

Right now, I find that I am breaking the rear tire loose on dry pavement and I'm not even trying hard. I would hate to see how it behaves when I make some mods and have to stomp on it.

I just want my Pavement and Off Road max performance.
 

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Discussion Starter #10 (Edited)
PS: I bought my Ecoboost truck, not because I am a die-hard Ford fan. Actually, this is the first Ford I have ever bought or owned.

I bought the Ford Ecoboost because all the great things I heard about the engine (I also have a soft spot for turbo charged engines) and from all great things in automotive/truck news magazines and Consumer Reports. Also, I thought it was one of the best looking trucks on the market and my local Ford dealer gave me a very good deal (as the Salesman said "What is it going to take to get you into a Ford"...and he met my price).

My wife is still pissed at me, she wanted me to buy a Toyota Tacoma ... and I was able to get my Ford Ecoboost "nice optioned" for the same price the Toyota dealer wanted for a Toyota Tacoma (and it wasn't even a TRD).

I'm sorry but I am old school when it comes to both Off-Road and On-Road performance. I already used my truck off-road where I needed both 4x4 and locking rear (and had the electronic locker kick out ... I would have prefered it to stay locked a little longer).

There are lots of mountainous back roads where I live and I want to explore them all. Hopefully I will get some pictures one day to post. I already have a few to upload from my trip to a lake near where I live.
 

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Okay, I get your points... I find the elocker to be perfect. If it's slippery out, i turn it on, launches are fine, it turns itself off when I go above 35mph, and back on when the speed drops below that. When it's not slippery, it stays off. IMHO, that's better for a truck than any kind of slip sensing differential.

You definitely do not want your axles locked at high speeds, unless you're doing off road racing, then we're in a whole different game.

I've got to say, the if you're regularly lighting up the rear tires on dry pavement, you have a very heavy right foot. I salute you sir. :)

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Discussion Starter #12 (Edited)
I've got to say, the if you're regularly lighting up the rear tires on dry pavement, you have a very heavy right foot. I salute you sir. :)

Actually I don't. I find it happens whenever I make a right hand turn due to the large amount of low end torque from the turbos. Its more the opposite where I have to be extremley light on my foot to avoid hearing it start to spin when at a dead stop and making a right hand turn.

Also, I found the locker kicks out at 25mph (40km/h). I double checked the manual and that is where it is supposed to kick out. I don't know how bad they are for plowing snow in Toronto, but I live in a rural area of Central BC. We go days before we see a snow plow, and usually they just put sand (or should I say "crushed minus 3/4").

We have snow on the ground for 4-5 months of the year and never see dry roads from Decemeber to February. A limited-slip would be suitable than the electronic locker.
 

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Sorry to bring this old thread back to life

Would like some opinions on running eaton truetrac front and rear for drag racing applications
 

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Sorry to bring this old thread back to life

Would like some opinions on running eaton truetrac front and rear for drag racing applications
Without a center diff, I wouldn't.

Also, steering gets very weird when the fronts lose traction, and both front tries are spinning at the same speed...
 

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I'd leave the front diff like it is
 
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