DLittle

So I changed out the fluid in the rear and refilled with Amsoil severe gear
75-90 and 2 bottles of friction modifier for the limited slip and took truck on drive and the rearend fills like it's grabbing when turning corners.
I went into school parking lot and turned a bunch of figure 8's to work the lube onto clutches and it is still grabbing. I've put 150 + mile on it since changing fluid. Is there something I'm missing or is the rearend wore out ? Everything was fine before changing fluid. The rearend made no noise and it wasn't grabbing.

Any suggestions ?

I dont want to hurt anything by driving it like this. I even took off the rear driveline and drove around to make sure it wasn't the u-joints. the noise was still there but not so bad. I looked at the u-joints and they feel ok.

big stinky

Did it do this before the fluid change?

DLittle

Everything was fine before changing fluid.

big stinky

Sounds like the fluid isnt working as advertised...
Don't know how well you know your amsoil dealer but i would try get a refund or something...

DLittle

I'm the dealer. I'll call Amsoil monday and see what they say.

Anyone else have any thoughts. Should i switch back to dino and see if problem goes away ?

Fred Swanson

Well the clutches only cost about $55 for that D70, so your call. I'd probably switch it back, if it worked fine with reg gear oil.

Bob Beauchaine

I've run Amsoil 75W90 since I changed the rear diff oil over 200,000 miles ago. I've change the rear diff fluid every 18,000 miles and always add 2 bottles of friction modifier. That being said just adding the friction modifier is not the correct - recomended way to add it. You are supposed to add 1 ounce at a time, test drive and add more, until the turning chatter goes away. I tried Amsoils 75W140 and found that it's water retention was too high - as per oil analysis. I feel that it just did not get hot enough to burn off the water other wise it too worked just fine.

I would wait until Dlittle calls Amsoil and see what they say.

Bob

big stinky

Curious to hear what they say too...

And why not... (switch back) Can't hurt anything. Will answer one question anyways...

u.s mma

when I had my rear re-done on warrenty work last november, I asked the tech about running synthetic. He showed me some little piece of paper that came in the power lock box that said not to run synthetic, only old dyno oil. Something about the clutches. So, Im out of warrenty, and still owe money on the rear, so I run 80-90w.

GasganoFJ60

I just did the same on mine. The rear oil hadn't been changed in forever and a day so I drained it and filled it with some dino Castrol 75-90 from the parts store, made a quick 500 mile trip, then drained again and re-filled with Amsoil and Mopar Trac-Loc.

What friction modifier are you using? Amsoil doesn't sell a slip additive to run on our trucks. Amsoil still says to use Mopar brand.

I haven't noticed any weird feeling of grabbing on turns, no matter how sharp. If anything I've noticed the rear tires turn much easier. Since the change it takes much less throttle to break the rear loose.

Confedpirate

I used Red Line with no modifier in and it work awesome and no grabbing when i turn corner and no noise

big stinky

http://www.amsoil.com/storefront/ada.aspx

And bump... Did you get it worked out?

92roughstock

In my experience, if the rear is grabbing around corners, all the friction modifier in the world wont stop the chatter/ grabbing- time for clutches.

DLittle

NO, called amsoil they said to drain and refill with out the additive. So I did still making noise. So I added a little bit of additive at a time till i used a whole tube and a little more. Still making noise. I put 100 + miles on the oil change still no good. So I thought that I would change it 1 more time and go with Regular gear oil and see what happens. I've got about 15 miles on new gear oil and some additive. I did 12-15 figure 8's in school parking lot and it still making some noise. Sounds a little better.

Does anyone have a good source for the clutches in the rearend ?

I have the D70 out of my wrecked 93 I could put in new truck. Just not sure what is faster. Removing the whole rear out of 2 trucks to swap or just pull the center and replace the clutches ?

Fred Swanson

Randy's Ring and Pinion had them when I did the D70 in the Ramcharger a year ago. Under $60.