89BlwnRs

I just put in a Zexel-Torsen take off from SLP. We used Mobil 1 Synthetic Gear Oil and a bottle of the GM friction modifier. Is it ok to use the friction modifier? Will the Mobil 1 suffice?

Any help is appreciated,

Jason

Vader

89,

My information is that the ST axle is a bronze cone clutch posi, so the GM additive is necessary. Synthetic oils are a preference for me, so my opinion might be skewed. At least you can't hurt it with the synthetic, and friction shoudl be lower. I use Mobil Syn in my Borg axle with additive, and it stays nice and quiet, but still locks when necesary.

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Later,
Vader
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"I'm gonna talk about some freaky sheet now..."
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89BlwnRs

Sorry Vader, but I think the Torsen T-2 (the one I supposedly have) uses no clutches at all. Any ideas? Here's their webpage if you can make anything out of it. I also just sent them an email.
http://www.torsen.com/T-2.htm

Jason

ede

the posi additive is for clutch type posi. it's a friction enhancer, or modifier, makes the posi clutches work better, and stay quiet. i've read post on here of people having noise problems when using additive other than gm.

surely MR. Vader couldn't be wrong could he about what you have? lets see thats 1 mistake for vader out of 4000 post, about 500 more mistakes and he'll be in my league.

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1st & 3rd

Vader

Thanks, Ed, but I think your mistake counting skills could be likened to a Florida election official.

I've never had the gear/gear differentials apart, so I was guessing. That's why I'm here - to learn like everyone else.

It appears that the cam action of the side gears (if they still call them side gears in these axles) might be hampered by the friction additive designed for cone-type clutches. The rest of the gearing shouldn't be bothered, but the cam/thrust portions might not like the moly particles hanging in there. It might not be a problem, but it's apparent that you don't specifically need the additive.

The synthetic gear oil should be no problem, since Mobil gear oil is usually 75W (ISO 32), which is very similar to straight 10W crankcase oil and automatic transmission oil.

Sorry if I didn't have the whole picture. Hopefully, Zexel will respond with some definitive email.

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Later,
Vader
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"I'm gonna talk about some freaky sheet now..."
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[This message has been edited by Vader (edited January 20, 2001).]

89BlwnRs

Thanks Vader, if Zexel responds to my e-mail, I'll be sure to post their respone here just so you know in the future.

Thanks again,

Jason

Kevin91Z

iTrader: (1)

The Zexel-Torsen posi does not use clutches, so the GM posi additive is not necessary. But it doesnt hurt. Our stock Auburn posi's DO need the additive, so dont forget that.

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GMTech

The Zexel Torsen (torsen stands for "Torque Sensing") uses a worm gear planetary setup. Therefore it does not need clutches, meaning no moddifier nessacary.

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89BlwnRs

Here's the reply I got from Zexel:

"You are correct in adding the friction modifier! The rear should have a GL-4 or GL-5 oil for the differential to properly function. There is a technical bulletin issued from GM on the use of the modifier because of a possible "rusty screw noise" in some vehicles. The modifier quiets this noise.

Thanks for the question.
"

Jason

Kevin91Z

iTrader: (1)

Wow, straight from the horse's mouth, so to speak. I guess the GM additive is required after all. Its only $10.

GMTech

Hmmm, GM has been known to do some crazy stuff to cover there butt, I guess use whats on the shelves already.

------------------
If you live in Southeastern US, check us out!
South East Thirdgen


ASE Master Tech + L1
Savannah, GA

'87 Trans Am
S/D TPI retrofit including functional PassKey, 22# injectors,
JET AFPR, Ported Plenum,
TB Coolant Bypass, Custom Cold Air,
SSM SFC, KYB Shocks, Boxed LCAs, Wonder Bar,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
-->14.97 @ 94.9 MPH<--

'97 Bonneville SSE

Vader

HOLY CRAP! Even when I'm way off, I'm right... go figure.

(I'd rather be lucky than good any day...)

Thanks for the feedback. I got to learn something today! After I studied the design at the link you provided, it was apparent that the moly wasn't necesary. The box reminds me a little of a gear/ball variator for off-road equipment, and they run with hydraulic oil only. I never suspected the TSB issue, let alone the "fix" that the GM engineers suggested.

Wait, while I get the rest of this egg off my chin....


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Later,
Vader
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"I'm gonna talk about some freaky sheet now..."
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