Any one else have this problem? When I make really tight turns, I get some whining from the rear end, seems to come from the axles, or either side, and not the chunk itself. Doesn't seem to happen until after the rear end gets hot from driving around, and it didn't happen until a few weeks after I installed the BMR LCA's.

Is it just the cheap stock rear end fluid getting hot an loosing viscosity? It is synthetic, though?

Could the BMR LCA's be the culprit or had an effect? And if I take it back to the dealership, will they blame the LCA's and not cover it under warranty?

Should I just try better rear end fluid? Mobil 1 or Amsoil?

The thing that gets me, it only does it when it's hot. :scratch: For now anyway, maybe the condition will worsen.

 

The only whining I hear from the back during turns comes from the passengers

 

 

I confirmed today that it only does it after it's been drove for a while, no noise when it's cold. I'm thinking it may be cheap stock diff fluid.

 

If the sound is anything like what I heard from the backend of my car, you've guessed correctly. My sound was noticeable after the car was warmed up after several miles of driving, and only occured when taking tight turns. The sound appeared after about two months of driving w/o any mods.

Check here, #4: Problems

The dealership knew of the issue, having heard it before on the Explorers . They switched out some of the differential fluid for a synthetic rear differential additive and I haven't heard it since. The additive stopped the sound as well as the physical rubbing that was occuring. Hope this helps.

Brian

 

Thanks for your reply!

I'm pretty sure I need an additive. I know they make a limited slip friction modifier additive, and I'm guessing my car needs some. I'm going to go ahead and order some Amsoil fluid and their additive, and I'm sure this will fix it.

I'll keep you all updated.

 

Mine has a slight whine on deceleration at about 50-55 mph. Will leave it a while as warranty goes to 100,000 kms so there is no urgency.

 

Allright, my final update on this subject:

The stock fluid is not good. It doesn't even look like lube, it looks more like some sort of silicone grease. It was almost clear in some places, and dark brown and black in others. Which leads me to believe it was too thick to get into all the tight places and was too thick to even mix well. The fluid smelled very burnt and stunk up the whole garage, even though it only had 2500 miles on it.

Drained it out throught the fill hole with a suction pump and tube (only got about 2.5 quarts out, but it wasn't all the way full when I started), then filled it back up with Amsoil Extrem Duty 75W/140 Synthetic Lube oil and Amsoil Limited Slip friction modifier. Took a drive until the rear end got hot, and started doing figure eights. The rear end made one whining sound for about a half a second, and hasn't whined since.

In other words, it's fixed: Stock lube stinks, Amsoil rules, rear end quite, all is well.

BTW, I'd advise taking off the diff cover, pulling it out through the fill hole was painful.

 

I've been hearing this noise after its been running for 45 mins or more... thanks for the update as I guess I know what needs done!

 

Add a bottle of the XL-3 Friction Modifier to your axle and the groaning noise will go away. Mine did the same thing. I added the Friction Modifier from Ford and did some figure eights. Noise GONE