Hey y'all... my truck has the TracLok limited slip axle with 3.55 gears. The TL has never worked since I bought the truck and I can't blame it with 255k+ miles on it, but that old worn out junk has to GO!

So I went and looked at the Aussie Locker (a lunchbox locker) and it says it will only fit into open/non-limited-slip carriers, so in order for me to be able to install it I have to rip that POS TrakLok carrier out and replace it with an open one which means tearing the axle apart, and it would be foolish to not rebuild it right then and there.

The other choice I have is I can find an open 3.55 axle and install the locker in it, then swap it in place of my existing axle.

Here's the problem... come tax time I am hoping I can afford some larger tires/wheels/lift, so I'll probably want to go to at least a 4.10 gear ratio. If there is an open-carrier 4.10 axle out there somewhere, I'd rather just get that to install my locker into instead. And of course I'd have to swap out my D44 pumpkin with a 4.10 unit as well, but that's no worry since I'm sure the junkyard has some.

So, was there ever anything offered with a 4.10 8.8 axle that will work in an OBS? Maybe I should swap a 10.25 in it... then I'd have to change the front axle out so it didn't look retarded with a mix of 1/2 and 3/4 ton (5 lug/8 lug) running gear.

 

Yes the 4.10 open was offered in the 8.8, it wasn't super common but they are out there. But if you're installing an aftermarket locker anyway just buy the open carrier at the same time... or just chose another locker that replaces the carrier completely... ie Detroit Locker or Trutrac for example. BTW.. the Ford TracLoc is setup super loose from the factory but it can be adjusted to near locker performance easily and for little cost.

 

Get the rebuild kit for the trac-lock and play with the shims till you can just barely squeeze the S spring back in. You can do it in the truck, you just have to slide the axles out. Replace the axle seals while you're at it. Then save your money for a real locker and not a drop in.

 

Ah but if I have to replace the carrier then I might as well just rebuild the entire axle since I'll have to go and set it all up again. I was hoping I could avoid that for now, since although I have helped with a rebuild before, I don't have enough experience to do it myself... not that I can't learn. Perhaps I'll buy an open 3.55 axle and swap that in for now while I take the current axle and learn to rebuild it into what I actually want.

I've never owned anything with a truly locked axle, always either just open or LS. Is there a difference in performance? Are you thinking that drop-in might grenade a stock carrier?

 

FYI... A Dana 50 diff from a TTB F250 was commonly available with 4.10s and will bolt right up to your stock axle beam. I'm regearing my Bronco and I'm using a 4.10 D50.

 

Open carriers don't need to support as much force as locker carriers do, so putting a lunch box locker in an open carrier (which is what you do with lunch box lockers...) does introduce a potential problem. That said, the companies designed and sell lunch box lockers because they do work and hold up well. But they aren't as bulletproof as a locker that was built to be a locker from the start.

Is there a difference in performance? Absolutely. When both tires get traction an open diff is ideal because it splits the torque evenly between the two sides so everything stays balanced (a loose limited slip does about the same). In contrast, when both tires get traction an automatic locker only drives the inside tire. That means you can get some weird torque steer issues as you get on and off the throttle. By the way, this shows up worse with a short wheelbase and manual transmission. Long vehicles and automatics reduce the effect.

Only driving the inside tire also means that tire is more likely to break free than with an open diff. The locker makes the inside tire do twice as much work as it would with an open diff. As it starts to spin it will catch up to the outside tire at which point the locker will engage. It does it hard enough that it's not uncommon to break that tire free too. That takes some driving skill to deal with (but nothing most car or truck people can't handle).

On the plus side, as long as one tire gets traction you can move. In a rock crawler, where lifting a tire is common, a locker is the only way to go.

Is a locker a good way to go on the street? It depends. I had a Detroit in the rear of my CJ5 and I have one in the rear of my Bronco. Both were put there for rock crawling, but I drove/drive both on the street a lot more than I rock crawl, and the tradeoff was well worth it to me. I also installed a Lock-Right (lunchbox locker) in the rear of my '95 F-150 SCSB. I never rock crawled with that, but I wanted the improved traction on snowy two-tracks when hunting. Still was worth the tradeoffs to me.

However for most on-road driving I think a limited slip is a better choice for a truck. The locker breaking the inside tire free gets worse when pulling a trailer with a lightly loaded truck, and you really don't need the solid behavior of a locker in most on-road driving, even in the winter.

That said, I'm personally not a fan of clutch-type limited slips. My first choice for a road driven truck would be a True Trac. I'd go with an automatic locker before I used a clutch-type limited slip.

I haven't addressed mud because I don't have a lot of experience with it, but my guess is that it's like snow in this respect. A little mud is probably handled fine by a limited slip, but serious stuff is probably better dealt with using a locker.

 

Thanks for the explanation, but the difference in performance I was asking about was lunchbox locker vs. a real locker. Most of my driving is on pavement since this truck is my daily driver for now, but when I do go off-road it would be great to have a locker.

 

I personally wouldn't install a locker on a daily driver street vehicle but to each their own. If you decide to go for the limited slip route, I installed a TruTrac on the rear Dana 44 in my '88 Jeep Grand Wagoneer and have been very happy with it. I do not rock crawl or push it too hard but it is pretty awesome for light to medium offroading and snow traction. I have done some light towing as well and it has held up just fine. I'm considering swapping in a truetrac for my F-250 which currently has an open diff.

 

The Lock-Right I had in my F-150 worked pretty much the same as the Detroits I've had. Probably the most noticeable difference was in favor of the Lock-Right. It isn't too uncommon for a Detroit to almost catch but then slip one tooth and kind of bang as it catches the next tooth. Both of my Detroits have done that much more than the Lock-Right did.

The Lock-Right did make a little more noise (clicking) going around corners. But it wasn't that noticeable.

The only "benefit" to a Detroit that I experienced was the peace of mind from having something with such a good durability reputation. My CJ and Bronco axles get abused worse than my F-150 did, so it seemed worth spending a little more. The F-150 was more of an experiment to see if a locker in a pickup would be OK. I wanted to be able to remove it if needed. As I said, the tradeoffs were worth it to me, and I never had any trouble with it in about 120K miles.

 

Great, thanks for the info guys, we'll see what happens here in a bit.

f100beatertruck, thanks for the info on the factory TL improvement... I may try that for the time being just because I'm so sick of the one tire fire (or one tire rooster tail if not on pavement).

And as for a locker requiring a different driving technique, I'm willing to adapt because to me the benefits are worth it.

 

Detroit lockers on street vehicles wear tires out alot faster. You could buy a Eaton E-locker.

 

I could, but the problem is selectable lockers are the most expensive type there is, and that won't be in the budget because I have other parts to buy too.

 

On the last truck I owned I put an ARB air locker in the rear. I loved it. When I wanted it locked it was locked. When I wanted it unlocked it was unlocked. Absolute control. I didn't do rock crawling but is was great in snow, mud and sand.

 

I don't think it's that significant, or at least it doesn't have to be. The only time they'll be at all worse is when your going around a corner and are accelerating or pushing up a hill or something. In that circumstance an automatic locker is only driving the inside tire, so it will wear more than it would with an open diff in the same circumstance. But unless you do a lot of heavy-throttle starts it's not going to make much difference. I got better tire life out of my Lock-Right equipped F-150 than I did my open diff F-250. I know the trucks weren't identical, but the locker sure didn't kill tire life either.

 

Hey, 460. 4.10's were offered in a LOT of rangers also and the carrier is a direct swap. I got lucky one day at the Pick and Pull and found the ugliest 87 Bronco you've seen. It was a half price wknd, thank god. Spent the better part of 3 hrs there with a buddy pulling little stuff and a set of dual shock spring mounts off other vehicles. He said, "How many trucks came from the factory with 4.10's in 'em?" I laughed and said, "very few". He walks over to that POS Bronco, first truck next to us, looks over at me and said, "What does 4L10 mean?" I about shat myself, LOL. They came home with me, front and rear.