LSD vs E-traction Control vs Diff-Lockers

[lighthammer]

Most of our trucks available locally have Limited Slip-Differentials (LSD's).

http://en.wikipedia.org/wiki/Limited_slip_differential

http://www.drivingfast.net/technology/differentials.htm

In theory, Limited Slip Differentials/LSD's are meant to prevent wheel-spin or slip (hence the name) in a low-traction situation, eg. driving in mud/sand or even on a slippery road.
The wasted torque in the free-spinning wheel is sent instead to the wheel with traction, hence giving you more power to get out of the slippery situation.

An open-differential (like found on most cars) will only give power to the wheel that's spinning faster. The outside wheel spins faster than the inside wheel, so an open diff allows them to spin at different speeds.This is handy for when the car has to turn a corner (i.e. almost everywhere you go in daily driving), so that the inside wheel to the corner won't spin & damage the axle. LSD's will act like an open diff, until some wheel-spin is detected at the outside/free-spinning wheel, then power is transferred to the inside/stuck wheel (this was meant really to help in off-roading or slippery road conditions where unexpected wheel-spin will be likely to occur).

Other anti-slipping mechanisms are also available, such as Electronic Differentials (found in the Navara Auto, Pathfinder and Prado, etc) which uses the ABS & Electronic brake-force distribution system to apply brakes to any wheel that's spinning freely without traction - this fools the differential into transferring torque to the other non-spinning/stuck wheel. More advanced versions of ETC can be found on vehicles like the Pajero and Evolution lancer (AYC - Active yaw Control), even Ferrari cars have them (known as E-Diff).


Differential Lockers (Detroit Lockers, Air lockers, etc.) act to lock together all four wheels on a vehicle, hence all wheels spin together at the same time. This is very handy in off-roading situations ONLY, where a vehicle may have one or more spinning wheels but no forward momentum. If used on a stable or high-traction surface like regular roads/highways, there will be differential-binding and you may destroy your differential gearbox. Basically, since all four wheels are spinning at the same rate, when you try to turn a corner the inside wheel try to turn at the same speed as the outside wheel, which stresses the gear-box and gives you unsafe handling.

[civic minded]

good info there dude - i think only james does the air locker here.

[V2NR 3.0]

Excellent read as usual...where can i get some of these lockers for my BT50 ?..

[civic minded]

i think the air lockers will cost close to 20-30K for them - need to find out from James to be sure

[lighthammer]

That's for both front & back?

Ironman 4x4 sells and installs them. They're located next to Tucker engineering in La Romain, I believe.


Send a PM to sureshot_james

[V2NR 3.0]

i think the air lockers will cost close to 20-30K for them - need to find out from James to be sure

I dont think its so much money. Wasnt there a group buy on this forum some time aback and the prices were really good. I would like to get a set of these which is controlled by a pump and can be turned on and off.

Felt these already in a former Suzuki i had...Sticking in mud is difficult with this device.

Hammer dude Is my van BT50 LSD (feeling to lazy to go look @ manual or diff)....places ive been with this thing makes me wonder

[lighthammer]

i think the air lockers will cost close to 20-30K for them - need to find out from James to be sure

I dont think its so much money. Wasnt there a group buy on this forum some time aback and the prices were really good. I would like to get a set of these which is controlled by a pump and can be turned on and off.

Felt these already in a former Suzuki i had...Sticking in mud is difficult with this device.

Hammer dude Is my van BT50 LSD (feeling to lazy to go look @ manual or diff)....places ive been with this thing makes me wonder

YES, the Mazda BT-50 & Ford ranger both come with rear LSD as STANDARD.
So no worries when going off-road, just make sure you have good, suitable tires.

[V2NR 3.0]

^ Hey man, thanks for the info. Managed to research it also. I would love to get a pair of ARB lockers for the front...

[lighthammer]

Scene bro.

Now, about the Navara, I believe the LSD comes as standard on both Manual & Automatic.

The Automatic has an electronic assistance to the LSD to prevent wheelspin - it works through the ABS and applies brakes to the spinning wheel when in a slippery condition.
This fools the differential into thinking the both wheels are getting equal traction and thus torque is supplied to both the spinning wheel as well as the wheel with traction.

I believe the Navara with the manual transmission has a manual form of LSD, similar to the Jeep Cherokee, Dodge Ram and other trucks. These run Dana Diffs, which aren't as durable as the Fuji Heavy Industries differentials found in the older Frontier and Subaru Impreza WRX's (and other vehicles). They're still effective though. The Manual navara doesn't have the electronic assistance through ABS like the automatic does - according to our local N&M salespeople.

What sense does it make to have 4wd on a heavy vehicle and not have LSD?

Can anyone confirm or refute this (with evidence of course)?
Does anyone with a Manual 4x4 navara want to help prove this?

[V2NR 3.0]

^ did u get the videos ?

[lighthammer]

yeah, good stuff man!!
Thanks to your LSD u were able to pull out the trucks in diistress.

With the proper application of limited amounts of torque, wonderful things happen

[lighthammer]

Went over to another Navara site - http://www.Navara.asia and did a google search on their site.

Found out there's a similar thread to this one asking about limited slip differentials in the Thai-built version of the Navara.

http://www.navara.asia/d40-drive-train/1754-rear-lsd-thai-built-navs.html

Seems that the Thai-built navaras have a "trac-lok" rear differential. This is a particular type of Limited Slip Differential.
It's clutch operated and has the clutches on the outside of the spider gears (which is unusual for differentials). This gives an appearance of an "open diff" (i.e. one that does not lock after a small amount of wheel-slippage in slippery conditions, or lock completely like a proper diff-lock).
These are known also as "Dana Diffs".


The D22 however has a different sort of differential, made by Fuji Heavy Industries (which also makes the limited slip differentials found in the Subaru Impreza WRX and Subaru Impreze WRX STi rally cars).
These diffs are a lot tougher than the one found in the D40 and are better suited for more serious off-road work, though still not as good as a proper locking diff (eg. an ARB air-locker).


Apparently it's a bit difficult to "shim" the dana-diff found in the D40 from Thailand, which would have made it act more like a diff-locker. It can be done though, but needs proper technical experience to avoid destroying your differential.


The spanish-built D40 has the same center lock as the Thailand-built D40 to lock the front and back wheels into 4wd mode, but the center rings are different diameters. The D40 from spain however has the same center as the D40 Frontier (american version of the truck) and thus they can both be retrofitted with the TruTrac lockers from the Nissan Titan (american truck).


That's about as far as I got with my research.
So I gather that the LSD in the thai-built Navara D40 LE isn't as robust as the D22 Frontier/Navara. I think that's why the Automatic version has the electronic braking-assist to supplement the mechanical Dana-diff in slippery situations. Dunno why the manual transmission version doesn't have the electronic braking assist.


I guess the best answer to this is to simply fit an ARB air-locker to the rear-diff and go on my merry way.

[lighthammer]

Found another youtube video that has a very clear demonstration on the differences between Open Diff's, LSD and Diff Lockers.


Have a look:

[speedaholic]

i want diff locks!

[Haunted]

i think the air lockers will cost close to 20-30K for them - need to find out from James to be sure

You sir are a mad man they used to run around 8k for 1

[lighthammer]

^^ I'll take two for the Navarkha please, thank you very much.

Still hadda meet with james to discuss the ironman liftkit for de bigfat girl.

[Dunman]

^^ I'll take two for the Navarkha please, thank you very much.

Still hadda meet with james to discuss the ironman liftkit for de bigfat girl.

LH,

I'll be interested in this as well. Does two qualify for a group buy.

[*Phoenix*]

Group buy....
count me in..
Thank You!

[lighthammer]

sure!

was also speaking to a guy named Andrew, who has a 8-inch lifted white navara (5 inch calmini lift + 3 inch body lift) plus 22-inch rims + Nitto Trail Grappler tyres.

He said we can check him for the lift kits, I was interested in a 3-inch suspesion lift from calmini.

[Dunman]

8-inch lifted!

Does it come with a step ladder, lol.

[MrCuddles]

wat does he hv for d Frontiers?? was tinkin bout a 2-3" body lift to get me started

[lighthammer]

calmini have plenty stuff bai cuddle.... check their website.
I go check for the Navarararara's and see what I can find, then post eet up here when I compilated all de datases.

[lighthammer]

after going to http://www.calmini.com i got sent to this website - http://www.purenissan.com/nissanmain.htm

Here's Calmini's page for the older model D22 Frontier('01-'04) suspension parts : http://www.purenissan.com/d22_suspension.htm

and here's the page for the '05-onwards D40 Frontier/Navara: http://www.purenissan.com/2005_frontier.htm

[droppa]

for the poor man, if u can find an LSD, u good to go, i will save alot of tires now, around corners i used to be real doin it, now, since i added an LSD rear centre, she jus cips around corners, and traction has increased dramatically......

[sliderz1]

Very good explanation on the development of the differential,and how it works in your car. Starts off a bit slow, but stick with it

its a cross post from the Ole Talk forum

guaranteed know how

[droppa]

open diff = stuck
LSD diff = take a chance
Locker = unstoppable

had one of my rear wheels in the air Saturday and she would not budge forward, had to roll back and take a sprint....

[sliderz1]

^^surf has LSD ??

[droppa]

mine was originally open diff, but i swapped out the rear to LSD, some Toyota come LSD

[lighthammer]

^^ Some of the local prado's also come with open diffs.
Not sure how to tell teh difference between them though.


AFAIK:
- Hilux = LSD
- Ranger = LSD
- B2500 & BT-50 = LSD
- Frontier 3.0 = LSD
- Navara = Open Diff - 4x4 manual model (did the spin-tyre test, both spun in opposite directions) & E-Diff (on automatic 4x4 model)
- Prado = either open or LSD, hard to tell unless you do the spin-tyre test
- Fortuner = LSD
- Dmax = LSD

[lighthammer]

open diff = stuck
LSD diff = take a chance
Locker = unstoppable

had one of my rear wheels in the air Saturday and she would not budge forward, had to roll back and take a sprint....

The front diff's are open, hence no power went to the wheels on the ground.
The rear-diff LSD is ok for mud, but even an LSD can't transfer enough power to the grounded wheel when all the vehicle weight shifted onto it.