Limited Slip Rear failure

[mels]

DANA 60 4:10 LSD, about 100k miles, always used the synthetic gear oil and the Ford additive.

All seemed to work well until when trying to pull on flat clean blacktop I smoked up the right side without so much as a nod from the drivers side.

My van is pretty heavily loaded down, and can't say that I've ever had it spin - especially on dry pavement. Heck, even on a snow-covered incline it would hop rather than spin.

What gives, gurus? Are these LSD's prone to failure? Is it time to look for a "real" posi? Can I find a locker that'll fit in the pumpkin?

In the name of full-disclosure, I was chained back-to-back to a Mercedes AWD SUV. I'm ashamed to admit he pulled me like I wasn't even in gear.



I am serious about getting to the bottom of the LSD issue, so thanks in advance for your help!

[sirnunya]

i think they are prone to going out. There are plenty of aftermarket options for that rear end though. Detroit locket, yukon powerlok, arb air locker, eaton positrac, eaton elocker, true trac, etc etc

[mels]

Roger that.

Any experience one way or another with the aftermarket units?

[Marty]

Actually are you sure it's a dana 60? The super duties come with a Sterling 10.5" rear... I'd imagine your's would be the same.

you probably got pulled backwards because you were spinning - so no traction and the other 3 wheels might as well of been in neutral.

When you're pulling someone else, stomp the breaks and slowly let off of them and apply the go pedal.

If you want to stick with a limited slip - True Trac alllll the way.

Or selectable locker or a detroit locker. Do not go with a full spool, mini spool, or welded spiders (can't do that with the factory LSD anyway) but if this is a daily driver make sure it's something that can unlock around corners

[mels]

Hey thanks for the info, Maintain. I say locker, but you're right I do need to turn that boat...

I did actually ease into the go pedal, the same way I drive it in the snow - as soon as I lose traction I'll let off sometimes coming to a complete stop (driveway or hill) and ease back on. Has never let me down.

Read the tag on the pumpkin just last Summer to verify I even had a one ton set-up as I've long suspected the van wasn't built as the one ton I'd ordered. Read the info off to my guy at the dealer who verified it was a 4:10 Dana 60 LSD. I wonder if I'd have been any better off with the Sterling?!

By the by, I'm 2WD only

[sirnunya]

the e250 and e350's have the dana 60 rear in most

[mschn99]

a limited slip is just that....it limits slip....

If you overcome one axle and get them spinning...u can still do a one wheel burnout.... There are clutch packs in the rear diff that try to keep the axles at the same rotational speed....but if you over power the clutch packs they will then act like a conventional diff...

[mels]

Oh OK it sounds as though thats exactly what I did then, and just over-powered the clutchpack.

Would a unit like the Detroit Locker afford me the true lock-up of both drive wheels and still allow them to turn independently of each other around a tight (well, as tight as an extended van can make it anyway...) turning manuever?

I'm really interested in learning more about that, and replacing the LSD with the True Trac as Maintain suggests or if the 'locker is a good alternative, go with something a little more progressive.

Thanks for your input, Marc.

[mschn99]

Originally Posted by mels

Oh OK it sounds as though thats exactly what I did then, and just over-powered the clutchpack.

Would a unit like the Detroit Locker afford me the true lock-up of both drive wheels and still allow them to turn independently of each other around a tight (well, as tight as an extended van can make it anyway...) turning manuever?

I'm really interested in learning more about that, and replacing the LSD with the True Trac as Maintain suggests or if the 'locker is a good alternative, go with something a little more progressive.

Thanks for your input, Marc.

yes.....a detroit or true track would give you more consistant lockup ability

[Marty]

Detroit TrueTrac is a gear driven limited slip. It won't wear out like the factory L/S application and will provide more positive engagment of both wheels. In fact, I had one in my old truck and it would unlock VERY nicely when going gently around tight corners. As soon as I firewalled it - it was positraction like crazy and would drive you around the corner.

The detroit locker also engages and disengages but to a much lesser extent. In fact while it's doing so it clanks, ratchets etc.. in my experience if you give it ANY throttle while going around a corner it locks up, skips the tires, slides, makes noises and creates some weird wear on the tires.

If you get any snow... I'd seriously reconsider a locker when thinking about a DD and especially if you plan on towing.