Limited Slip Diff Upgrade
 

I have a 2008 F-250 SD with the gas V10 that I use for hauling my race car tailer. It has a 4.10 regular diff. I didn't order the limited slip diff and I regret it.

Are there companies that I can buy and instal a LSD (4.10 is fine) for my truck?

Thanks,
Chris

A Detroit True Trac should solve your problem...

A guy in the Excursion forum installed one on his truck and wishes he would've done it sooner. He said that even with the snow on the ground, the truck felt so confident in 2wd the didn't really need to use 4wd.

As soon as I get some money, I plan on doing the exact same thing since my truck has an open diff too.

:-X25 hi CP Louie and welcome to FTE :-X25

There are a number of very good after market limited slip differentials. Tru-Trac, Detroit and Auburn make quality equipment.

If you are going to spend the money, don't get a stock LS. The gear style limited slip units (Like True-Trac) work a lot better. This cut is from

Ford 10.25 Differential Lockers Auto Parts: AIR LOCKER,ARB,SELECTABLE LOCKER,LOCKER,10 1/4,10.25,10 1/2,FORD 10 1/4,FORD 10 1/2,DIFFERENTIAL,FORD 10.25,DETROIT,DETROIT LOCKER,10.5,STERLING,LOCK RIGHT,LOCKRIGHT,POWERTRAX,LIMITED SLIP,POSI,POSITRACTION

True-Trac limited slip for '83 and newer Ford 10.25" and 10.5" with 35 spline axles. The True Trac limited slip uses a worm-gear design to bias torque from one tire to the other, providing extremely smooth operation. Since there are no clutches in this unit, there are no parts to wear out and no need to run limited slip additive in your oil.

Thanks for the info. I think that the 2008 F250 is a 10.5 inch ring gear. I will call them and ask.

Thanks MS for service to our country as well. Chris

ARB is running a special thru the end of April. You get a "free" air compressor with the purchase of one of their locker differentials... just an FYI.

I just spoke with Barney (not related to the purple dinosaur :-missingt) at Eaton who informed me that they plan to make the eLocker for the Sterling 10.25/10.50 rear axle. All he could say was that it would not be available in 2010... maybe 2011.

I second the ARB. Locked when you need it, open when you don't. I have them installed in both the front and rear of my F250.

Where do you live? Do you drive in snow?

A clutch based limited slip is more "grabby" than a worm gear based limited slip. The gear based also does not need "friction modifier" added to the lubricant whereas the clutch based limited slip needs to have the correct amount of friction modifier added to work properly.

If you don't drive in snow, any of the limited slips will work well for you. If you drive in snow, I would suggest the True Trac limited slip; however, realize all traction aids when "locked" (even the True Trac) will change the handling characteristics of the truck somewhat (just less with the gear based True Trac).

Randys Ring and Pinion is a pretty good place to purchase your differential stuff; although, if you look up 4x4/driveline/differential in the yellow pages you will probably find a place that will order and install whatever you want. I know it'll double the price, but if you're having differential work done, think about putting one in the front as well (if you have a 4x4).

I just don't know if I can wait that long, a year from now. "Maybe 2011" is the best they can give you? Yeesh. I'm needing some traction, like right now! :-X20



Back on topic
I'd look real hard at the Eaton (Detroit) TruTrac limited slip differential if I was wanting a limited slip.

I've run an Auburn, and it was the cat's meow, but those things eventually wear out, just like an OEM limited slip. The auburn was real aggressive off road: punch the gas and watch two rooster tails of dirt, mud, sand, or snow spray from the rear view mirror. But after, say, 50,000 miles it wasn't quite as good. Then by the time it was 75,000 miles is was not very good at all. Finally by 100,000 miles it was completely back to open differential. It's a single use product. Non-rebuildable. when it's done, it's done.

The TruTrac uses worm or helical gears to bias torque instead of clutches. The good news is that it doesn't wear out or performance doesn't degrade over time. The bad news is that (I think) there isn't any preload on the unit. That means in extremely low traction situations such as a tire on ice or a tire off the ground, the unit may not be as effective as a clutch driven unit where the preloaded clutches can still provide some torque biasing ability to the other wheel with traction. But that's the disadvantage of any limited slip... at some point they will still spin one tire.

If you're going to get a limited slip, I think the TruTrac is the best choice.

seminaryranger is right, and I should have mentioned that. There isn't preload with the Truetrac. One thing you can do though is apply a little brake while also accelerating slightly. This gives the differential the "bias" or whatever you call it to think there is a little traction. So, if you have one in the rear of your truck you can click the e-brake just slightly until it engages, or give it a little brake, and it will usually engage a front or rear Truetrac. But, if you're on ice or have a wheel off the ground, you may not get it to work on it's own, without the use of a little braking.

I have had the true trac in the back for close to a year, and can't say that I had to brake slightly to get traction on both sides. Had a good test on a river bed, gravel/sand while pulling someone out, and both sides dug down nicely. I don't have any ice, or winter around or I would test it out on some for the one tire spin.

One question. What tires do you have? If you're running the stock Continentals I would replace those before getting into any limited slip differential system. Those things are terrible on anything but dry pavement.

I do have the stock Continentals and they are part of the problem I am sure. That might be great advice. I don't drive in snow unless I get caught somewhere. This is 2 wheel drive that I bought for highway use to pull the trailer.

Sometimes I have to drive on grass, and we did get stuck in a few inches of snow when my son backed one wheel off the road.

These have all been really good comments, and i appreciate everyone's help. I will have to sort through this. I have air on board, I just put in a compressor. I had no idea that someone made an air operated LSD. I have air bags and I put in a little regulator for that as well. Chris

I agree - deal with the tires first and then consider differential.

For your education, the ARB is not a limited slip, it is a true selectable locker.
When it is engaged, the axle shafts are completely locked together like with a spool - no differential action whatsoever.
They are fantastic if you learn how to use (when to lock or unlock). But they are $$$. You get what you pay for!

Personally, I am very excited to hear about the Eaton eLocker and will be watching for them! They work the same as the ARB (true open or true locked), but use electricity rather than air for a much lower installed cost.

I recently had True Tracs installed in my F250, and I can say I no longer fear my 100 yard long driveway during big snowstorms :-) There is some sideslip on ice, but I am quickly learning to adjust my driving habits to minimize the effect. I now have a real 4x4 instead of a 2x2 with a marginally effective LS. Just my .02 worth...