2004 F150 Differential Clutch Packs???

[BigBen]

Hey guys,
My friend that helps me out on the K5 has a 2004 F150 (65k miles) with a strange shudder coming off a stop while turning. The dealership says it is the clutch packs in the differential and that they'll happily change them for $800.

Was wondering, have any of you guys done this part? How hard, and what's involved? We don't want to get involved with rear-end setup and backlash, etc....

Any thoughts/help would really be appreciated!

-Ben

 

[bigblock72]

Have you tried adding some friction modifier? It sounds like someone changed the gear oil and didn't put any modifier in with the new oil. 4 ounces is recommended but it may take 8 to get it to stop shuddering.

 

[BigBen]

The guy at the parts place mentioned that he could add some addative to help it out. He did it about a couple weeks ago and it didn't really get any better.

I don't know that the diff has ever been drained, I'll have to ask him.

 

[bigblock72]

If you added friction modifier then you'll need to replace the clutches as per service bulletin. You'll need clutch kit 6L1Z-4749-A if it has a 9.75 axle or F5AZ-4947-BA if it's a 8.8.

It's not too hard to replace the clutches, you won't have to mess with any adjustments when you pull the carrier out. Use the Ford 75-140 synthetic oil ONLY to prevent any future problems. Do not use 75-90 with the new clutches.

 

[BigBen]

OK, looks like we better figure out which axle he has.

We've both done a lot of car stuff in the past, but no real axle work. Thus, we're a little hesitant about digging into the rear end of his DD.

Sounds like pull the cover, slide the axles outward, pull the carrier, change clutches, reverse for install? We've been looking for pictures or a write-up online, but not luck yet.

Is there a source similar to GMPartsDirect for Ford parts?

Thanks again for your help so far,

-Ben

 

[Jason4x4]

also might be worth pulling the carrier and then taking just the carrier to a differential shop and have them do the clutch paks, shouldn't be too much $$.

 

[BigBen]

Maybe not a bad idea.

Part of what's killing us is neither one of us even knows what a clutch pack looks like!
Anyone got a picture of one?

-Ben

 

[bigblock72]

http://www.eaton.com/EatonCom/Produ...ucts/Products/Differentials/PosiLSD/index.htm

 

[BigBen]

So, is that the actual thing we're dealing with?
If so VERY COOL!

Thanks man!

-Ben

 

[bigblock72]

Not exactly but very close. You won't have the springs to deal with but other than that it'll look like that.

The easiest way I've found to get the Trac-loks apart is to mount an axleshaft in the vise splines facing up. Put the carrier on the axle so the splines engage the side gear, remove the cross pin bolt and then the cross pin. Once the pin is out grab the carrier and turn, the shaft should hold the side gear stationary and force the spider gears to turn and fall out. It may be difficult to turn so be prepared. When the spider gears are out remove the side gears and clutches, WATCH the order of the clutches so you can reinstall the new ones in the same order. Soak the new clutches in oil or friction modifier before reinstalling, restack the clutches in the order removed (unless there are instructions in the kit that say otherwise) reinsert the spider gears and turn the carrier like you did in disassembly (you'll have to work a little harder so make sure the axle is clamped tight) reinstall the cross pin and bolt and you're done.

It isn't difficult and really doesn't require anything more than a big vise on a sturdy bench and about an hour to do the job, so don't be scared.


Chad