chef150

I'm new to posting, so be kind. I've read a lot of posts on this topic but didn't quite get the answer I was looking for so here it is.

I have a 2010 XLT Super Crew with just over 115K on it. 5.4L V8 4x4. About 3K ago, there was a rubbing noise and shimmy to the rear end after hauling a lot of weight in the back. After reading here, I replaced the lube in the rear diff and added the friction modifier, and though it helped a little, it didn't solve the problem. I'm convinced the clutch packs need to be replaced. After looking at my options, I'm thinking about putting in a Spartan Locker and forgoing the LS. I live in the mountains, do a moderate amount of hauling, and 75% of my miles are on the highway. I get some of the negatives about the locker, but the positives seem to outweigh them and the ease of install seems to make more sense (I'm better than the average joe, but by no means a pro).

So overall thoughts on the above?

And - No matter what i choose to do, do I need to replace the axle bearings and seals?

me1234

I personally wouldn't put a rear locker on a daily driver. Have you seen the Detroit Truetrac helical limited slip? The system doesn't use clutches so it's as maintenance free as you can get. It's not temperamental on the highway or around turns as locker would be and i've gotten my 2000 2wd scab through 8 inches of snow with it.

Also yes, I would replace the bearings. I had shop install my diff, so I'm not sure if they replaced the seals too.

chef150

Love this idea. I had never considered or even read about this until your post. I appreciate the info. Do you know if this fits within the stock carrier? I didn't read the install instructions, but it looks like a straight forward swap for the spider and side gears.

NASSTY

The Truetrac replaces the stock carrier. You should only need new carrier bearings and don't run synthetic gear oil.

http://www.ebay.com/itm/Eaton-Detroi...lV~BpO&vxp=mtr

chef150

So here's something fun - the axle code on the door sticker reads H9 which is a 8.8 3.55 code (unless I'm reading it wrong), but when I go to the ford website and put in my VIN, as I sometimes do to get stock part numbers, it only comes up with 9.75 info. The cover is 12 bolt so I'm now thinking the 9.75 is right, but what gives with the door code?
If I go with the Truetrac, the carrier bearings match to that right? Auto part websites give me lots of options.