Torsen differential Q's

SouthernViking

New member
acylon":1asst1xd said:
YES! That little faint M under the fin could be our ticket to identifying these friggin torsens! :D

Thank you boosted blue!

But we need more proof, we need to have an open st185 see if there is no M. And we need a Torsen st185 and to verify the M.

Marty, I love having Torsen in the rear. It seems to make the car more predictable in corners. And makes it drive alittle more lika a rear wheel drive. Better for inducing throttle on oversteer.
Now c'mon guys , y'all aint playing fair .......
here i am in Australia , with a JDM st185 ,{registered as an '89 model} dont know if its built in '89 , '90 , or '91 :doh: coz it dont have the built date stamped on the plate on the firewall.....
i've read this thread a few times today and am still non the wiser :twisted: , but
i do know its a GT4 that i have ............and i've posted here coz curiosity got me , so i slid under the G'car and saw my rear diff is just like the one which ACYLON posted a pic off on pg. 5 in this thread/forum .. same plug , the #1 on the housing AND the M or 3 or 8 ??? :oops: {whichever its meant to be}
off my details {following} , what can you all tell me {and wont it be great if i get 4 diferent versions} :lol:
DETAILS :
model : E-ST185-BLMVZ
engine : 3s-gte 1998 cc
frame : ST185-0002352
color : 6K8
trim : FQ10
trans / axle : E150F - 734
plant / built : A54
And finally , according to my rego. paper , the engine number is
3S9097526
:roll: I'm tired of presuming what i have and it would be really nice if all you
"officionado's" could put your minds to work for a few minutes and find some details :wink:
i have pics in "gallery" and yes , its a narrow body , which you folk apparently dont see many off and also RHD .......
i've owned it since Dec '06 and have'nt had time to decipher it all yet ..
All i know is , when i stomp the "fast" pedal , it goes fast and i hear the "hairdryer" whistle a bit 8) {WHICH IS SOOOO SWEET} ....
When i rev to 3k at standstill on bitumen and ease the clutch , it gets up 'n' boogies with no loss of GRIPTION {aussie slang for grip & traction :p }
When i do the same on gravel , i get equal wheelspin on all 4 wheels
and straightline acceleration when it grips as i plant 3rd gear
Overall , i dont mind what driveline i have as long it drags me to where i wanna go , but since you guys have so much info at hand , i figure , well , why not try and set you all a challenge to help me out :)
BY THE WAY , if i've posted this in the wrong spot , i apologise :shock:
 

alltracman78

Active member
I thought I would add this here too, in case anyone missed my edit a few posts up.
I have previously stated the RC rear diff has a different ratio.
I was wrong. It is the same as the regular 185 ratio.

Southern Viking,
I just checked my 92. It came with a TORSEN rear diff. Codes are below.
737/E150F

I also had a 93 that did NOT come with TORSEN rear. Luckily I am moving my storage this week, so if someone would be so good as to bump this thread to remind me, I can check the door code on it [I still have the dr door].
Also, I have a wrecked 91. I don't know which is in it at the moment, but I can at least check the door sticker, assuming it's intact. :p
 

SouthernViking

New member
Hey Eddie , Thanx mate , for the link to that write-up.... seems most of that info matches , but i'm still wondering about the "E" in the model line and also the "734" in the trans /axle line when you all are only mentioning 737/767....................................
i guess i'll lok again later aft i've had some sleep
ciao for now :?
 

CMS-GT4

Active member
I wonder if that code really has anything to do with theh rear lsd. I have a feeling the whole code is just a gearbox code, and anything with a 151 is standard with lsd.
 

CMS-GT4

Active member
So we have to find a door with 737 and 150. That is the only way I think we might verify that code tells us anything about a rear lsd.
 

Razzo

New member
well im in the middle of trying to figure what my rear end has. Its a early production model 89 but a 5th gen. Its JDM so its narrow body, 2 pot brakes, etc. I've heard that most jdm models came with an lsd? i'm really crossing the fingers that only alltracs came with the open diff.
 

eddie_gt4

New member
CMS-GT4":3rrf3s3e said:
So we have to find a door with 737 and 150. That is the only way I think we might verify that code tells us anything about a rear lsd.

you don't have to find anything... it's just under your nose :D
at least EDM ST185's have a VIN plate (just under the hood) with all needed info :smokes:

I've posted it in other thread:
VIN plate pic

SouthernViking, I guess that "E150F-734" is a tranny & diff code of some (all?) "pre-facelifted" JDM ST185's :oops:
but whether 734 = viscous LSC or Torsen, I don't know :shrug:

btw, other sources on i-net also mention such code...
jus go google with a "E150F-734"
 

TomsGT4

New member
Ok, lets make this interesting.

First off, we're not talking about viscous coupled diffs, we're trying to find out if our differential is open type or a limited slip torsen.

Second, if you see the post on the 4th page of this thread, 3rd picture, you'll read that "the torque sensing LSD is an option on the All-Trac/4WD models". Which means that this could be either factory or dealer installed. I'm not sure if the dealer would perform such an install at the time on a brand new vehicle, but if they did than that pretty much shoots to hell any hope that a vehicle identification plate will help.

Third, I think that Josh's post from the other thread:
CMS-GT4":3kfos3u4 said:
Ok, so I have been doing some reading and I want to test out if this is a method to determine if you have lsd w/o opening the case.

I need a volunteer who knows they have a torsen in the rear and a volunteer of a known open lsd.

We need to try TEST 2. If this works, this might be a great help to the community.

How can you tell it's a TORSEN?
Well I'm no expert but there were a few obvious traits - stock Toyota diffs are TORSEN or open wheel - sometimes a diff might be changed internally with a mechanical action diff. TRD or CUSCO etc - When Juzza got his diff he scored one of these diffs by accident, on sharp slow turns the inside wheel chirps and squeals a little bit as it tries to keep up with the outside wheel - a TORSEN diff is super smooth. Anyway on the wrecker showroom floor the TORSEN diff has differences to an open wheel diff. With a TORSEN LSD on a workshop floor there are a couple of tests to do.

First is the spin one axle and the other axle spins same way - Torsen. If the other axle spins other way then go to test 2.


Test 2
Spin the input shaft of the diff. One wheel will may spin freely with the other stationary. I can hold one axle still, spin input shaft and the other axle will spin free. If I try to stop the spinning axle with my leg, just let the spinning axle rub my calf for example - the axle I am holding still with my hand will instantly start spinning in same direction. As soon as any torque is applied to the spinning axle - torque is transferred to the stationary axle and they spin together. TORque SENsing.

A metical clutch type LSD or cone type LSD tends to spin both wheels in same direction the whole time to a degree. There isn't so much "free wheeling" as available in a TORSEN.
[/b]


...probably this is the best way to tell what diff you have.
Look at page 4 of this post, last two pics of that post. It pretty much verifies what is said above.
1. Keep the input shaft fixed & spin one of the output shafts, if the other output shaft spins in the opposite direction, it's possible you have an LSD.
2. To find out for sure if it's an LSD spin the input shaft, and put force on one of the axles in the direction as shown in the diagram (same direction the ring gear travels). If the other axle spins together in the same direction as the force you applied, LSD.
 

ion_four

New member
The followiing is either a solution, of sorts, or just another question to go unanswered ;)

Does anyone have a rear diff apart (either open, Torsen or Viscous, whatever) from which they can take some measurements? I'd like to know:

1) Ring gear diameter, inner and outer.
2) Number of teeth on ring gear
3) Number of teeth on pinion gear
4) Width from outside of one carrier bearing to the next.

I'd like to know this, without ripping my car apart, because I have a Toyota LSD in my garage (not from an All-trac) which looks to be about the same size. I'm curious if this, or something else, might be an option for us.

PM me if you have this info. Otherwise, it'll be a while before I do it myself, since I just changed my diff oil :p
 

Toxygene

Active member
So I am curious. One time I had all my axles replaced and while the shop had my car in the air, they turned it on and put it in gear. All my wheels were spinning in opposite directions. Would that tell me anything about if I have an LSD in my car?

I don't think I have any other way of finding out other than ripping parts apart since the previous owner did some extensive mods to the car and I don't have a list of all of them.

Thanks!
 

ion_four

New member
Toxygene":evi7muo4 said:
So I am curious. One time I had all my axles replaced and while the shop had my car in the air, they turned it on and put it in gear. All my wheels were spinning in opposite directions. Would that tell me anything about if I have an LSD in my car?

I don't think I have any other way of finding out other than ripping parts apart since the previous owner did some extensive mods to the car and I don't have a list of all of them.

Thanks!

In a nutshell, that suggests you have an open rear diff. However, I have a clutch-type LSD on another car and if I spin the input shaft, the wheels turn in opposite directions, IIRC, but if I turn one of the outputs, the other output turns in the same direction, especially if resistance is applied to the other output...I think it might just be wearing out, though :p
 

CMS-GT4

Active member
Here is a pic of my plug. I am going to look for a scope in hopes of seeing some helical gears.

img4831zd2.jpg
 

BriinumsBo

New member
after reading about 5 discussions on alltrac.net about torsen, i guess nobody knows nothing about how to identify them. While everybody thought Torsen is when the box code reads 151F/767, someone comes op that 737 is torsen. wtf.
anyway i have european version, 767-151f, non-CS. I want to replace the oil and i`d like to believe i have Torsen.
If i turn the rear wheel, the other turns slowly the oposite direction..

what gear oil should i use? is synthetic motul 80w-90 ok ? (synergy or gear, does the name matter?)
 
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