Tremor front limited slip?

Raspy

Tremoraholic
TOTM Winner
Founding Member
Joined
Nov 2, 2020
Messages
509
Reaction Points
1,349
Location
Northern Nevada
Current Ride
2021 F250 Tremor 7.3 Lariat
Current Ride #2
2023 Xpore Roamer1, 2013 Jeep Rubicon 2dr
I thought the Tremors were supposed to have a nice Dana gear type limited slip in the front. Not. Here are some pictures of mine with the cover off. The only thing it may have is friction disks behind the spider gears, but I'm not even sure it has that. Very disappointed! This looks like a plain old open diff to me.
 

Attachments

  • 1-2.jpeg
    1-2.jpeg
    50.8 KB · Views: 500
  • 1.jpeg
    1.jpeg
    63.2 KB · Views: 387
  • 1-1.jpeg
    1-1.jpeg
    58 KB · Views: 382
It’s a friction disc style. I looked it up in the workshop manual about a month ago. It’s the most common form of limited slip and what Ford has used in rear diffs for years. That was the best you could get in the rear before they came out with a selectable locker in I think 2011.
 
I thought we were getting the Spicer Trac-Lok geared limited slip.

Here's a link to the Spicer Trac-Lok.

 
Here's a link to what 4 Wheel Parts lists in their Tremor article. But the parts list shows this for rear axles only.

Dana Spicer Dana 60 Track Lok - 707427X​

Dana Spicer Dana 60 Track Lok - 707427X

707427X.jpg



(0) | 0 Q&A

Lowest Price! Guaranteed!

Get 10% Off Orders Over $500 | Select Pick Up In Store At Checkout

Qualifies for Free Shipping





  • Dana 60
  • For Use With 4.10 And Down Gears
  • For Use In Rear Applications Only
  • For Use With 35 Spline Axles
  • California Residents: WARNING
 
Last edited:
It’s a friction disc style. I looked it up in the workshop manual about a month ago. It’s the most common form of limited slip and what Ford has used in rear diffs for years. That was the best you could get in the rear before they came out with a selectable locker in I think 2011.
That looks like a very weak system with minimal torque biasing. And, of course, if one front wheel is off the ground, it will do next to nothing. It might help if both front wheels have traction, like in sand, but I'm not very optimistic.
 
I've had disc limited slips for years, and they are better than open for sure. Yet, they always leave me wanting for more - just like in my Tremor.

Mine works great on a muddy road with no crown. For anything where tires leave the ground, the computer running the ABS in slippery mode is more effective than the diff.

I still need a part number for a Detroit Locker or Yukon Locker. I might consider ARB, but I dislike air and electric lockers due to one more potential point of failure.

Ed
 
I forgot about the ABS in slippery mode. If that works as well as it does in my Rubicon, it will be fine.
 
I forgot about the ABS in slippery mode. If that works as well as it does in my Rubicon, it will be fine.
It's not a locker, but it doesn't suck. Way better than an open front diff from the 1980's with no traction management.

Ed
 
Meanwhile, here are a couple of notes about changing the oil in the diffs:

In the rear diff, one of the lower cover bolts, the one on the bottom right, is the drain plug. You do not have to take the cover off to change the oil, just remove that one cover bolt. The diff is an M275, with 10.8" ring gear and the recommended oil is 75W 140. I used full synthetic. I changed it the first time at 1,400 miles after a very easy break-in, and it had metal in it (normal). I changed it again today at about 12,000 miles and a lot of towing, and it had less metal in it. Getting broken in nicely. The fill plug has a magnet. The cover bolts take a 12 point 13mm socket.

On the front diff, the cover has to be removed to drain and it has no gasket. It is sealed with silicone. Today was the first change, at about 12,000 miles and the oil has a small amount of metal in it. No problem. The fill plug has no magnet. The cover bolts take a 9/16" 6 point socket. Metric on the rear, Imperial on the front. Recommended oil is 80W 90. I used 75W 90 full synthetic.

The axle shaft U joints, just inside of the wheels, are greaseable and have conventional zerk fittings. Be sure to grease them! I used Lucas Red-N-Tacky because I have a lot of it in stock. A waterproof marine grease is probably best for those.

I don't know if the front driveshaft U joint is greaseable. Do any of you know?
 
I installed a Truetrac in front of mine . It’s way better than the factory front diff . Both front tires spin. There is a “heavy feel” to the front steering when 4wd is engaged
 
Back
Top