Locked vs LSD
 

I've gone down the rabbit hole. I'm preparing to regear to 4.88 for 33s. I have a 2wd 99 limited. And want better traction to both wheels...so naturally while regearing lsd's and lockers came to mind. I've searched over and over and now have no better clue of what to do. Some threads state lockers are better for when a wheel leaves the ground as it will still distribute power to both wheels ( seem helpful considering 2wds are really 1 wheel drive and God forbid your power wheel leaves the ground) others say lsd are better, where others state lsd leave you open to the one wheel off the ground being the one that now free spins.

I was under the impression a locker will lock the axles all the time to evenly distribute power, but release a wheel that loses traction, and engage that axle when traction is noted and pressure reapplied to the locker.

I was under the impression that a lsd would lock both axles until one broke traction or spund faster, at that point it would pulse to distribute all power to traction side, then test the free axle for traction, and once equal pressure was reapplied both axles would be locked again.

Now I'm just confused.

I don't off road to crazy, occasionally loose dirt/ sand , hills, shallow creeks and streams. I'm mostly getting myself to climbing areas then to camp away from the crowds.

Any insight would be appreciated.

This is all you need to know and I'm certainly buying what she's selling. :D

https://www.youtube.com/watch?v=CFdJza0AbeA


And I agree on the rabbit hole....just find a decent T4R3G with 4WD.

Good luck,

Eddie

A factory elocker will lock the rear differential so both wheels spin exactly the same come hell or high water. It's that simple, makes no difference if one is off the ground.

There are also lunchbox lockers that I believe lock the axle if it starts spinning freely but I hear they break and arent reliable.

Don't know much about LSD but I wouldnt want to mess around with that, too much to go wrong. But I'm no expert. I hear it's quite a trip tho.:wink:

Classic movie. A posi and a lsd are the same thing. [emoji16]

I haven’t posted on my build thread but I went with a Grizzly locker with 4.56’s on my 2wd. Not a hardcore wheeler but it did make a huge difference in going fishing and camping spots. Truck just goes!

The re-gearing is wonderful!! Went with 4.56 because I am running 31’s. I will say that with 31’s and this gearing 70 mph is about 3k rpm. Was going to go with the 4.88 but I don’t have 33’s. I think even with 33’s the 4.56’s is ok. Around town it really scoots! Not a race car but peppy. When you hit the gas with the locker and gearing you can feel the torque and the rear “hooks up”. It’s not even too noisy. Just pops once in a while when you come out of a turn and it locks up again. Nothing too bad and I like my rides smooth and noise free.

I am happy with the choice I made! I went with ECGS.

100% agree.

Yes and IIRC, Posi-Traction is GM's name for an LSD.


Eddie

That grizzly setup from ECGS was exactly what I was looking at...except the 4.88. Read through some of your thread. Kinda a similar story. In laws bought this thing new in 99 now they are 70 and don't need it. I got attached since I've been driving this thing since 99. Can't bring myself to sell it. Rather mod it to be most useful/practical to my needs. I've only gotten stuck once since 99.

I have factory 4.88 in my second gen, and had it rebuilt by ZUK (gearinstalls.com) and he's the man. Period.

That being said, I went with a Detroit TrueTrac. It's a completely mechanical limited slip. No clutches or friction modified fluids. And it has been so friggin great I can't say enough good things. Major increase in traction off road, zero difference on-road, zero maintenance, no switches, no air no nothing. And you can "cheat" it with the e brake trick if one wheel spins.

But it will never be a locker. It's damn close. But not a locker. I don't regret it and never will, but it all depends on your goals. And frankly, being 2wd changes everything. If I were you, I would go selectable. Either air or electric or retrofit a 3rd gen's elocker into your housing. A lot of work but then you have both worlds at the push of a button. I would guess a full time locker would annoy you but then I'm thinking of how annoyed I would be. TrueTrac would be my second option for you if you don't want to go selectable.

Yup! You get attached and when people say “just sell it and get a 4wd” us usually don’t understand. It’s a way to keep the memory going. Dad still loves the truck!

If and when you get the new third, follow the break in procedure. Took a month for me but I was patient. After the 500 mile oil change that oil will be black with a silverish hue. Btw...the new third with locker is a lot heavier!!

Almost forgot..if you get one with the aftermarket housing you might need to sand/grind some of the opening of the rear axel housing where the third goes in. Mine was wide enough at the adjusters where it would not slide in.

Detroit TrueTrac LSD for the win. Unless you’re trying to rock crawl it will be a helpful mod all the time (wet roads, sand, dirt, etc).

There are multiple types of LSDs, each with different characteristics.

The Detroit TrueTrac is a gear-type that transfers torque based on available traction up to a maximum ratio (between 2:1 and 5:1, depending on design).

There are viscous LSDs that transfer torque based on a difference in wheel speed.

There are also clutch-type LSDs that also transfer torque based on torque differences, but in a more on-off type manner (generally) than a gear-type or viscous LSD.

Then you have lockers (that are still technically in the "LSD" family) - both ratcheting (full-time) and selectable (part time).

Its is a deep rabbit hole.

If you want something you never have to think about, get the TrueTrac. If you want max traction off road get a selectable locker (OEM electric or ARB air). If you want the cheapest option, get a ratcheting locker.

-Charlie

To add to Charlie's information: the TrueTrac's are Torsen differentials. They use the principal that a worm gear can turn a spur gear, but a spur gear can't turn a worm gear. :happy:

Another vote for the LSD TrueTrac. I put mine in to avoid the dreaded one-wheel burnout. I did it for very different reasons than everyone else so far but when I do take it out in the snow, dirt etc. it's great because it's always on. 2WD, 4WD doesn't matter since if one of the rears starts to slip or squeal it kicks in and gives me traction again. Now I can't even do burnouts... all that power hits the road!

Is it worth it to spend the extra $$$ for and ARB air locker or Eaton Zip locker? Vs the True Trac?