Rebuilt SureGrip Noise When Turning

Seeking input from the well of knowledge before I drop this 3rd member again.

A few weeks ago I grenaded my SureGrip and it consumed two spider gears. I bought new:

• Spider Gears
• Side gears
• Cross pins
• Carrier and Pinion Bearings
• Ring and Pinion
• Mobil 1 75w-90 gear oil w/o additional friction modifier

Following the factory service manual I disassembled and rebuilt it, followed with ring and pinion setup.

Condition I have is heard within the video below. Any turn input results in that popping sound, at faster speeds it's an obvious gear noise. The differential does not act like it's a spool or excessively tight, it just sounds horrid.

I have 15 miles or so on the rebuild, initially the diff did not make any noise. It became apparent when I went to make a u-turn at ~mile 7 of my test drive. The gears and diff have no problem with straight line driving and are smooth and quiet.

Given the low mileage and the fact this is the first SureGrip I have messed with, I assume there is not a "break in" on the differential itself, right? In 15 miles of driving, the spider gears only differentiate only a few feet.


Video is of a light turn into my garage.
https://youtu.be/PP2lIY0B_hY
[video:youtube]https://www.youtube.com/embed/PP2lIY0B_hY[/video]

I did this same thing, then I went out and bought a Dana S60.

Ya that sounds like the axles ringing. My 4x4 with clutch danas front and rear, the rear would do that after diffs got hot pushing snow. I tried everything, ended up with castrol syntec in it and its fine now after 100,000 miles. I changed the clutch packs from steel on steel to lined, still did it. Castrol worked for me, nothing ever broke, and the rear is only 30 spline, it still does it after a long tow with weight in it. Still bothers me, waiting to bust an axle.

Dr Diff suggested I add Ford friction modifier and give it a go. We shall see.

IS this a clutch or spring style sure grip ???
Myself, I would pull it back out as it obviously is not "clutching"



(EDIT) OOOPPPS didn't see the part about not using the friction modifier. Definitely give it a shot.

w/o additional friction modifier

that friction modifier is there for that reason

From Doctor Diff's site "limited slip additive is recommended for Mopar 8.75" and Dana 60 clutch or cone style sure-grips. 1 bottle controls clutch sticking and chatter."

http://www.doctordiff.com/friction-modifier.html

The FSM is very specific about using the correct lubricant with a SG.

treed, lol

The dana brand modifier did not work for me, am told ford stuff may work better. I will tell you this, I got a lifetime supply of dana 70 and 80 powerlocks in the mid 90s as owners returned their new trucks complaining about that chatter and ringing. Chrysler swapped them out for new ones, modifier did nothing back then.

Thanks for the feedback all.

I am going to try the ford modifier and go from there.

From reading the synthetic gear oil bottle and some online research, no additional modifier was going to be needed with a limited slip. Perhaps my mistake was assuming that information applied to clutch types, hopefully the new modifier will cure my woes. I'll post up results when available.

Hate to play Monday morning QB but you need to soak the clutch plates in friction modifier before assembly as per Doctor Diff instructions.

Gus

I had the same problem with my Dana 60 but I solved it with the Chevy version of the friction modifier!

Doesn't have to be Phord or Chebby brands... any brand will work, They are all the same: Mopar has it too ( if it cares )



https://www.amazon.com/Genuine-Mopar-4318060AC-Limited-Additive/dp/B000TTEX8W

Had the same problem with the GTS. I used the GM version. I didn’t add enough. Added another bottle, solved the problem.

Just wondering. Will too much additive do any harm?

One thing that will help is to do slow figure 8"s in a paved parking lot, Ford suggests 10 slow figure 8"s. The figure 8"s causes the clutches to open up and unload, That lets the modifier get between the clutch plates and the friction discs faster. Ford also recommended this to be done yearly (according to the Service Manager at one of the dealerships I worked at that used to work at Ford back in the 70s.

In answer to Mopars4ever, the modifier allows the clutch discs to slide on the clutch plates, I suppose too much probably isn't a good thing, but the question is how much is too much? The bottle posted earlier is 4 oz, given how much lube is in the diff, I wouldn't think 2-3 bottles would be too much, but if you approach 25% modifier, I suspect your looking for trouble. Gene

I put 2 bottles of the mopar brand in my 9 1/4's in middle of summer to shut them up. The extra seems to only keep the locking action a bit looser than normal. Better than feeling/hearing that racket back there.

So far so good.

I ran in the Ford Friction Modifier yesterday for a few minutes on the jackstands and let it sit overnight, per Dr. Diff's recommendation.

I drove it for a brief period this evening starting out with some low speed figure-8's. It clunked a little more on right-hand turns initially but seemed to smooth out by the end of the drive.

I won't be leaving home without friction modifier, synthetic lube or not, lesson learned!