I think the Mech LSD in the taco is done...

Well my 2008 TRD sport mechanical LSD over the past couple of years seems to getting weaker and weaker. It's always had the proper service (I've owned since new) and the truck only has 122000 km on it. Now it's acting pretty much just like a open diff. So here's the magic question.... How much are they to rebuild clutch packs or has anyone bothered and just put in a ARB or Detroit locker? I like having the LSD diff as up here we get lots of snow and rather not have to run around in 4WD. Right now it sucks as one wheel will have traction but if other is on ice /snow it just breaks loose and I go nowhere fast. I do use it off road as well, going to my favorite hunting spots. So let's here your suggestions.

 

Well I've only rebuilt open diffs, never a LSD. But if it were me, I'd either just install a locker or try to source out a replacement LSD from a wrecker. Mind you, rebuilding diffs isn't that hard if you're mechanically inclined. I'm sure you could read up on LSDs online somewhere and figure out what needs to be done/parts you'd need to buy. It would definitely require removing the differential from the truck though, so if you've got the space to do it, that might be your best/cheapest option.

Sorry I couldn't be more help, but at least this will bump your thread back to the top so others can see it, haha..

 

check out the detroit truetrac

 

Proper service? What specifically? What oil and what additive?

 

The Sport's with the true mechanical/clutch type rear differentials require fluid changed using a special fluid with friction modifiers.

If you think yours is toast I'd check or change the fluid first. It could be that the friction modifiers have broken down.

I don't recall which years what the true limited slip, I think it might have changed to the simulated version around '08...

The dealer should be able to get you the right oils. You could try searching here, too. I don't have one of these trucks.

 

'08 was the last year for the mechanical LSD.

 

Toyota sells a kit that supposed have spider gears an clutchpacks. Last time I looked at, it was around $150. You don't need to reset gears. Carrier should split in half to remove clutchpacks. Before that I would try putting new gear oil, something like Lucas. I tough my LSD is getting weak but after putting new oil it has been going. Personaly I would stick with that mechanical LSD.

 

Hey guys thanks for the replies. I had the dealer change the diff fluid f/r at 55,000km and I just changed it again at 112,000km diff was weak so I changed oil.(it has 123,000km now)When I changed it I used Castrol hypoy c 80/90 and a 4oz bottle of LSD additive. Now looking at the pictures and description on bottle did I need the additive?? It's just Dino oil not synthetic. It stated it's for limited slip diffs but didn't say it had friction modifiers in it.

 

One other thing I jacked up the truck today, both wheels off the ground and in park. I grabbed the passenger tire and had no trouble rotating the tires. Passenger turned CW and drivers side turned opposite direction like an open diff. I read on TW that it should take 150lb on a torque wrench to move the tires and see if LSD engaged. Here is the method I tried posted by member BlueT.


Originally Posted by NumNutz
I'm not well versed in this area so I'm looking for advise.

Symptoms:
-Obstacle where one rear wheel has limited to no traction, no much/if not any power is going to the wheel with traction
-If you were trying to drift around a turn, the inside wheel would continue to spin with the other wheel not breaking loose.
-However, when doing a burnout, both wheels spin

I've heard clutch plates within the Mech. LSD can go bad. Could this be the issue I'm experiencing? Other ideas?

BlueT's response:


Well esy to find out.
1. Lift rear end
2. Keep it in park but no parking brake
3. Put torque wrench on one lugnut. set Torque wrench to 150 ft-lb
4. try turning wheel with torquewrench
5. If wheels turn, instead of TrqW clicking something is wrong with clutch packs or oil in diff.

 

Clutch pad lsd's do wear out just by nature of them.... They are always going to be in a clutch slipping state when cornering which will wear out the clutch packs no matter what oil or additive you use. With as much kms as you have op... Nothing you are going to do with the current clutch pack is going to work... Either rebuild it with a new clutch pack, or go another route.... Factory elocker etc

 

Thanks for all the replies guys. Well as a last ditch effort before I start throwing parts at the rear end, I dumped the Castrol Hypoy C Dino oil that I added the LSD additive to, and refilled it with 75/90 Lucas Synthetic oil. If this doesn't work then its back to the drawing board of deciding on either fixing what I have, a ARB, or a street-able style locker. Detroit Locker/trutrac, Auburn pro series, etc.

 

Thats correct, so either you have problem with clutch packs or oil (oil is more probable).
Oil you listed looks like it has additive already in, so by adding additional additive you probably made the system slip more. ( I have done that when combating grind with Synthetic oil)
Its looks like its your first change, don't get discouraged. Its hard to get that oil right the first time.
Lucas worked for me and I did not add any additives to it. Right now I have only Lucas, and 70000 miles on my LSD. I also live in snow/ice place so my LSD works hard in winters. My clutch packs are still strong, I just tested again driving in 2wd with one wheel on the ice.

 

75,000 miles is noting for these rears if you keep up on the fluid changes, but I see you have not been changing it routinely. I have 94,000 miles on mine and before swapping it out for a

$1,110 ARB RD129 Air Locking Differential

ARB RD129 it ran flawlessly but I also never ran it for more than 30k without a fluid change and normally I did that at 15k.

ARB and Detroit are going to be a ton of money. IMO you should rebuild your rear and start changing the fluid more often.

I would never use Synthetic in a LSD rear.... first off there is no need if you take the time to change the fluids regularly and second synthetic is known to cause issues with these rears.

Keep it simple.

Use regular dino oil and add in a friction modifier.

Just an FYI you loose your mechanical LSD with the ARB locker and driving in snow with an open rear BLOWS o0nce your used to the mechanical LSD....I just swapped mine in the beginning of winter.

 

OP, get a detroit truetrac. It's a gear driven limited slip, so it will last a lot longer then a clutch driven LSD, and you can run regular diff oil. And since it's gear driven, if you ever get into a off camber situation with 1 tire off the ground, you can pull the e-brake and give some gas and it will lock up, something you can't do with a clutch driven LSD. Great product for what I hear, can't wait to get mine installed

 

Synthetic is exactly the wrong thing to use, I'd think. More slipperier; when you want some grabby friction additives in there.
$150 for a new cluchpack isn't bad. I'd go that route, if it proves bad.

 

I heard they were total junk from a reliable source who installed one and couldn't wait to get it back out of his truck.

$1,110 ARBRD129 ARB RD129 Air Locking Differential

ARBRD129 FTW!

 

Idk who you heard it from, but the truetrac is loved by pretty much everyone one here who has one. That's what made my decision to get one. You sure it's not the locker he's talking about? You're the first negative review I've seen, and I did a lot of research

 

shiiiiit ... yes the locker. He hates it. Well should say hated it....it's gone now.

 

Ok haha. Yes the truetrac is an LSD that acts pretty much like a full locker, and an open diff on the street, detroit locker is a full auto locker. I heard the powertrax no slip is a little easier to deal with. The detroit locker is basically like a lockright

 

If you changed the oil and it didn't have friction modifiers in it, you'd know almost immediately. The diff would chatter & rumble and especially while turning.