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Diff fluid

chameleo78

NAXJA Forum User
I have a '94 sport with a limited slip in the rear. The Haynes manual I have calles for "friction modifier". Anyone know where I can get this stuff? All the typical auto stores just look at me funny when I ask for it. Is this something that I have to get at a dealer? Thanks.
 
Yes, you can get it at a dealer. When I bought mine at wally-world, it was already added to the oil.
 
Dealer only as far as I know, costs about $10 for a small bottle, head on down to your local jeep dealer... they will hook you right up and won't give that confused look as they take your money with a smile :)
 
Like Haleyes said, it's available in many oils at the parts stores. I'm not surprised that the 'typical' auto parts stores couldn't answer the question...that's pretty typical (pun intended).
 
How bad it is to run without the modifier. I'ts probably only been a couple hundred miles, but I needed to drive it. Do you think I did any thing terrible to my diff?? I hope not. Thanks.
 
Friction modifier helps the clutches work - if you don't use it for a while, the clutches can start to chatter.

You should be able to find it right next to the gear oil at your local, and (I think) GL-5 lubes have it already included - check.

I paid $8 for a bottle of RedLine FM this past week-end, since I just found out that my new 89 has Trac-Lock... Cool.

Mix rate on the stuff is usually <10% by volume, so the small bottles are plenty.

5-90
 
chameleo78 said:
How bad it is to run without the modifier. I'ts probably only been a couple hundred miles, but I needed to drive it. Do you think I did any thing terrible to my diff?? I hope not. Thanks.
add it sooner then later as the side effect will be that your trac lok diff will turn rather fast into open diff.
 
Yucca-Man said:
Like Haleyes said, it's available in many oils at the parts stores. I'm not surprised that the 'typical' auto parts stores couldn't answer the question...that's pretty typical (pun intended).


pun n.
A play on words, sometimes on different senses of the same word and sometimes on the similar sense or sound of different words.

;)
 
Looked at some Castrol gear oil in Wal-mart and the bottle said limited slip diff ready so you may be good with that stuff. If you've already drained and changed like was said earlier you need to get some in asap. When I worked for a parts dept in a dealership the mechs put in when called for without question and gave a deer in the headlights look if you asked them what would happen if you did not use it. The little bottle from the dealer should be good for maybe two uses. I never had any luck finding it at local parts stores but maybe they carry it around your area. If not its definately worth going to the dealer to avert in potential damage in your diff.
 
NAPA has it and PEP Boys has it. Next to the gear lube. It's in a small tube, you only need a little bit, use the whole tube. Try asking for posi-traction additive.
 
Jeep dealer had it for about $8. Added it tonight. Now, how do I test my limited slip to make sure I didn't fry it?? I had the rear on jack stands and when I put it in gear both wheels turned. In neutral if I spun one wheel by hand the other one spun the same direction. Any thoughts?? Thanks.
 
Not a gear head "pun intended" but I would think if it drives okay with no clunking or other noise in the rear end you should be okay. The damage might not show for a while though so keep your ears open for unusual sounds from back there. I could be wrong but I you should be okay.
 
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