Hi guys, just changed differential fluid and pulled clips out of stock lsd. Used mobil 1 75w90 and the friction modifier from advanced auto. When I tow my boat I get get that growl when taking off from a dead stop or taking off after a turn around. Do I need more modifier or is there something else going on? The bottle I used was 7oz so I thought that would be enough.

 

Far as I know if you pulled the clips you shouldn't need the friction modifier at all anymore, but I'm not 100% sure on that

 

Pulliing the clips doesn't change the fact you have LSD. I believe the manual specifies four ounces, but that likely is not the cause of the growl. How much 75w-90 did you use? Also, if you tow, you should probably use 75W-140.

 

Yep, you still need the friction modifier and the rear calls for 75W 140.
The growl is likely something else in the pumpkin.
This is from the 03 manual but still applies:

REAR AXLE - 9 1/4
DIAGNOSIS AND TESTING
GEAR NOISE
Axle gear noise can be caused by insufficient lubricant,
incorrect backlash, incorrect pinion depth, tooth
contact, worn/damaged gears, or the carrier housing
not having the proper offset and squareness.
Gear noise usually happens at a specific speed
range. The noise can also occur during a specific type
of driving condition. These conditions are acceleration,
deceleration, coast, or constant load.
When road testing, first warm-up the axle fluid by
driving the vehicle at least 5 miles and then accelerate
the vehicle to the speed range where the noise is
the greatest. Shift out-of-gear and coast through the
peak-noise range. If the noise stops or changes
greatly check for:
² Insufficient lubricant.
² Incorrect ring gear backlash.
² Gear damage.
Differential side gears and pinions can be checked
by turning the vehicle. They usually do not cause
noise during straight-ahead driving when the gears
are unloaded. The side gears are loaded during vehicle
turns. A worn pinion shaft can also cause a snapping
or a knocking noise.

BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged.

Bearingnoise can be either a whining, or a growling sound.

Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differential.
If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.

Differential bearings usually produce a low pitch
noise. Differential bearing noise is similar to pinion
bearing noise. The pitch of differential bearing noise
is also constant and varies only with vehicle speed.

Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.

Hope this helps?
AL.

 

Yep, pulled clips does not an absence of LSD make. You still need the modifier. I've not used Mobil 1 gear oil, but as a synthetic, I'd imagine it has some in it already, no? The addition a little extra is usually not a bad thing though.

I would say about 4 oz. is plenty if the gear oil already claims to have it. I used Royal Purple in my Grand Cherokee and it still chattered a bit around turns, mainly backing up and cutting the wheel, despite RP having it. 4 oz. shut it right up.

My first guess would be that if the Mobil 1 already has it and you added 7 oz. your problem may be just the opposite, too much friction modifier causing the clutch packs to grab?

Of course I'm assuming that there was NO noise before you changed the fluid, ruling out another issue within the pumpkin...

 

Thanks for all the responses. Probably should have mentioned 2wd so I think it calls for 75w90 but I could see how the 140 might be better for towing. I have also noticed that it seems worse when within the 1st few miles when its cold. Hopefully Hammer is right about my improper balance of lube and modifier, might pump some out and put just lube back in and see if that helps 1st. Not liking the other problems from abarmby's manual( especially when I found one of the w's off the clips in the bottom of pumpkin that I hoped caused no damage). Thanks again guys for the help.

 

So with the clips removed, does the unit still work as a limited slip or does it work as an open rear? By the time I learned about the clip problem it was too late for my axle

 

The majority of the folks here think the clips were used for installation of the clutch packs and left in because it was easier and cheaper then taking them back out. It still works like a lsd and I've read quite a few people diving just fine without them after they were removed which is why I removed them all after finding a piece of one clip in my pumpkin.

 

Yep.....I ran 20+k miles before I installed my DTT without clips.
She seemed fine and even worked like it awlays did.
Al