Limited Slip... lets be clear on this issue

[tony4380]

hey guys...sorry for the long post

...so ive read several threads on this topic on this site about our less than par OEM limited slip diffs...

(05 f250 CC 6.0l 4x4 6spd. man)
i have concluded:

-over 20k miles... they dont work like they used to/should...even when serviced
-service interval... 20k miles 75w-140 synth 3.3qts (my application)
-some people have more luck than others...
-wet leaves/grass owned not only me but anther member
-limited slip additive helps the clutch pack SLIP and NOT grip??
-royal purple and the 08 aluminum diff cover is a decent upgrade
-my friends f150 chirps 35's on dry pavement in turns

---i have added royal purple 75w-140 full synth...
---i changed the cover to the 08 aluminum cover...

end result: my limited slip still sucks and is very limited

note: i only put 3 quarts in... as i didnt feel that .3qts would make a difference ---does it?

ive got 200 miles left under 3/36 warranty...

so i guess what im looking for is... advice, insight, or knowledge that will help me resolve this issue...

 

[Kleetus]

Go buy a detroit trutrac and hand it to the dealer to install.

 

[JLDickmon]

-limited slip additive helps the clutch pack SLIP and NOT grip??

keeps it from shuddering.

 

[atk]

have you thought about the AIR LOCKER....it is a little more money. you will have an open differential for normal driving(should be a little easier on fuel)
and when needed(at a push of a button) a full locker....i am leaning towards
this set-up when money allows....hope this helps...

 

[Bolt]

Eaton makes an electric locker now too, haven't heard much about it though. Don't need an air source and a solenoid to activate it.

 

[BigDaveZJ]

First off, open vs limited will make NO difference in fuel economy.

You can "help" the limited slip out a bit by pushing the e-brake down a couple clicks too if you want. And remember that in many low traction situations a locked diff is WORSE than an open one.

The limited slip additive will allow some slippage of the unit, allowing you to safely maneuver through turns and such. Without the additive, the differential will lock up more often and cause abnormal tire wear and lead to some interesting handling characteristics.

 

[atk]

First off, open vs limited will make NO difference in fuel economy.

You can "help" the limited slip out a bit by pushing the e-brake down a couple clicks too if you want. And remember that in many low traction situations a locked diff is WORSE than an open one.

The limited slip additive will allow some slippage of the unit, allowing you to safely maneuver through turns and such. Without the additive, the differential will lock up more often and cause abnormal tire wear and lead to some interesting handling characteristics.

maybe not for a diesel engine, but it did on couple of my gasser`s with a full locker, not a limited slip(there is a difference, but i think you know that, since you go crawling) these were my experiences with previous vehicles....


and you are right about the additive....

 

[BigDaveZJ]

I run a spool on my Jeep, and was still able to get the same 17 MPG on the highway that I did with a completely open diff, so I guess YMMV.