View Full Version : Rear Diff Clutches
guspech750
03-26-2010, 10:58 PM
So as it turns out so far. My rear diff noise has not gone away. Parking brakes are good. If I end up buying new clutches, can I use the Cobra rear diff clutches and buy the F-150 spring that I have heard some members mention? Will they work with the the original differential? Does anyone have a part number buy chance? I would really like to get this taken care of before Kentucky. Thanks.
Joe
Is this the right parts and part number by chance?
http://www.fordracingparts.com/parts/part_details.asp?PartKeyField= 6942
fastblackmerc
03-27-2010, 02:32 AM
That is the right one.
FordNut
03-27-2010, 05:29 AM
You're going to need spider gears, too. Might as well just get a new differential unit.
You're going to need spider gears, too. Might as well just get a new differential unit.
Maybe. But Ford sells a rebuild kit for the gears as well, (they refer to them as side and pinion gears) I did that to the truck 8.8 and held off on the rebuild for about 20,000 miles, when I did rebuild it, all those parts were reused and in good condition. Besides its relatively easy to replace the side/pinion/clutches in a decently equipped home shop for about $225, a full rebuild is gonna be in the $1,200 range...
ctrlraven
03-27-2010, 08:25 AM
^^^A full rebuild of what?
Friction modifier is really for the noise, I would try changing the fluid first since that is the cheapest thing to check first.
^^^A full rebuild of what?
Friction modifier is really for the noise, I would try changing the fluid first since that is the cheapest thing to check first.
The entire axle assembly including ring, pinion, bearings, shims, lube etc. If he replaces the diff he would need bearings, etc...well you know the drill, once your in there one thin leads to another...not a bad thing but can get pricey ;)
I dont know what noise he is having but friction modifier will only help with "chatter" in that it makes the clutches slip more easily. I agree on the lube, Id do a full drain and refill with some high quality synthetic. Most aftermarket axle lube has FM in there already and it will give him a chance to look things over, he is going in for the clutches anyway. If he has any other type of "noise" there is a long list of things that could cause it.
EDIT; I found the other post. Id open it up drain itand have a look. If the fluid doesnt have any metal in it and all the gears (including side, pinion and Ring/Pinion looked good Id fill it with some RP and have a go...
Just sayin
guspech750
03-27-2010, 11:18 AM
I am going to drain it this weekend check it as best as I can and refill. Thanks fellas. Hopefully its all torn up so I can go spend some money:)J/K
justbob
03-27-2010, 11:30 AM
I'm sure everything is fine.
Drewstang
03-27-2010, 12:06 PM
I had no noise in my rear end, but found my spider gears in horrible shape with missing teeth and quite a bit of wear. I tried to order just the gears from my local dealer, only to find they are a part of the carrier assembly which was discontinued at the time. I took it to another shop who was able to locate a carrier unit and get everything installed.
-Matt-
03-27-2010, 12:29 PM
Maybe. But Ford sells a rebuild kit for the gears as well, (they refer to them as side and pinion gears) I did that to the truck 8.8 and held off on the rebuild for about 20,000 miles, when I did rebuild it, all those parts were reused and in good condition. Besides its relatively easy to replace the side/pinion/clutches in a decently equipped home shop for about $225, a full rebuild is gonna be in the $1,200 range...
What? Where are these prices coming from? I just bought a brand new ford cobra diff with the carbon fiber clutches for $190 :rolleyes:
What? Where are these prices coming from? I just bought a brand new ford cobra diff with the carbon fiber clutches for $190 :rolleyes:
No doubt, but the installation requires pulling the axles, and diff, removing the drive shaft and pinion/crush washer, removing the ring gear from old diff and pressing on new, swapping or replacing diff bearings and setting up the rear.
The labor is going to be much different than just swapping the clutches and side gears, nothing but the axles have to be messed with (C clip removed and axles slid out, pull clutches, rotate pinion gears out, pull side gears, reverse install), all the rest stays in the car......I did that on the truck 8.8 myself, takes about an hour with the vehicle on jack stands.
And the full rebuild is just that, a full rebuild (all bearings and seals, ring and pinion, shims, RP fluid, etc, etc) not just swapping in a new diff...costs based on personal experience, the Marauder got a full rebuild with 31 spline axles, new diff, 4.10's. RP fluid about 2 years ago, I bought the parts for about $500 (ring gear, axles, diff, bearing and install kit) the labor to install was $800
Rebuild Diff In Vehicle
Clutches +/- $80
New spring $??
Side gear and pinion kit +/- $80
Cupl few quarts of RP Fluid $30
Misc sealants $10
GreekGod
03-27-2010, 07:47 PM
Like Drewstang said, the OEM carrier and (internal) side/axle & pinion gears are no longer serviced. I believe they changed the angle of cut of the gears (probably why you wouldn't want to use the old style anyway).
The metal debris from the failed gears may have contaminated the entire housing and all bearings! My left axle wheel bearing/axle shaft/seal failure, and differential/pinion gear failure led to tiny flakes of metal throughout the axle tubes and other internal surfaces.
I recommend installation of all new bearings, 4.11 ring/pinion (with a solid pinion spacer), a Detroit Locker, & 31 spline axles, after you remove, strip, & power wash the bare housing. The flakes are very difficult to remove.
:bows: I have spoken. :bows:
MrBluGruv
03-27-2010, 08:08 PM
No doubt, but the installation requires pulling the axles, and diff, removing the drive shaft and pinion/crush washer, removing the ring gear from old diff and pressing on new, swapping or replacing diff bearings and setting up the rear.
The labor is going to be much different than just swapping the clutches and side gears, nothing but the axles have to be messed with (C clip removed and axles slid out, pull clutches, rotate pinion gears out, pull side gears, reverse install), all the rest stays in the car......I did that on the truck 8.8 myself, takes about an hour with the vehicle on jack stands.
And the full rebuild is just that, a full rebuild (all bearings and seals, ring and pinion, shims, RP fluid, etc, etc) not just swapping in a new diff...costs based on personal experience, the Marauder got a full rebuild with 31 spline axles, new diff, 4.10's. RP fluid about 2 years ago, I bought the parts for about $500 (ring gear, axles, diff, bearing and install kit) the labor to install was $800
Rebuild Diff In Vehicle
Clutches +/- $80
New spring $??
Side gear and pinion kit +/- $80
Cupl few quarts of RP Fluid $30
Misc sealants $10
I'm taking the MM into the shop this thursday, and labor they quoted me for doing the gear swap to 4.10's, rebuilding the trak lok, and swapping out a DynoTech driveshaft (basically a rebuild + gear swap + driveshaft swap) at about $395 bucks. I'm getting it in paper before they start working, but even other places only came in at about $100 more locally.
GreekGod
03-27-2010, 08:13 PM
... rebuilding the trak lok, and swapping out a DynoTech driveshaft (basically a rebuild + gear swap + driveshaft swap) at about $395 bucks. I'm getting it in paper before they start working, but even other places only came in at about $100 more locally.
If it is the OEM carrier, the internal gears are very likely chipped (junk), and you will need a whole new assembly.
============================== ==============
MrBluGruv
03-27-2010, 08:14 PM
I guess we'll see Thursday. :(
Come to think of it, what'll I end up with if that's the case? Would I conceivably be worse off than before the swap and rebuild?
I'm taking the MM into the shop this thursday, and labor they quoted me for doing the gear swap to 4.10's, rebuilding the trak lok, and swapping out a DynoTech driveshaft (basically a rebuild + gear swap + driveshaft swap) at about $395 bucks. I'm getting it in paper before they start working, but even other places only came in at about $100 more locally.
Thats about the going rate for that work, I'd work with that. Its quite possible that Ford no longer offers that side gear kit, I did mine in 2003...but its worth a look if needed you might find some NOStock parts... If you upgrade to 31 spline, look for Crown Vic PI listings (2006 and up I think), thats what I used for the 31 spline carrier and axle swap on my car, the axles were cheep and came with the ABS exciter rings installed.
Really I'd open it up and go from there...its possible you dont have any major issues. Just make sure you trust the shop. If there it a boat load of shavings or chipped gears Id bite the bullet and consider a rebuild including axle bearings and the rest of the work. Do you know the history in the car? The axle bearings were a problem and they would cause some noise and chew up the axles...that might be a possibility. I am not trying to get you worried, just passing along my experience.
GreekGod
03-28-2010, 06:22 AM
...Its quite possible that Ford no longer offers that side gear kit...but its worth a look if needed you might find some NOStock parts... Heres a tip, when searching for parts look for Crown Vic PI listings (2006 and up I think)...
...The axle bearings were a problem and they would cause some noise and chew up the axles...that might be a possibility...
The original type differential (case), pinion & axle gears are not available. It is not "quite possible that Ford no longer offers the gear kit", it is a fact. You don't want the NOS parts anyway, because they fail. The newer model replacements require the newer type differential case.
When my left rear axle bearing surface failed, it was totally silent. The first indication of a problem was a leaking axle seal.
============================== =================
The original type differential (case), pinion & axle gears are not available. It is not "quite possible that Ford no longer offers the gear kit", it is a fact. You don't want the NOS parts anyway, because they fail. The newer model replacements require the newer type differential case.
When my left rear axle bearing surface failed, it was totally silent. The first indication of a problem was a leaking axle seal.
============================== =================
Whatever dude...your right of course, axles never make noise when the surface/bearing fails, the stock stuff sux....thanks for the help
http://www.teamfordparts.com/partlocator/index.cfm?action=getJointLocat or&siteid=214270&chapter=&Sectionids=23,0&groupid=10047&subgroupid=20042&componentid=61683&make=23&model=Marauder&year=2003&graphicID=FVP080&callout=16&catalogid=1&displayCatalogid=0
The side gear and pinion kit is available in the aftermarket as well.
justbob
03-28-2010, 08:36 AM
Guys, this rear was in perfect shape in every way two weeks ago untill they changed the fluid with friction modifier "all ready added" into the new fluid. There isn't $1200.00 worth of worn out gears. Are you all trying to give him a heart attack or what? It's just a little chatter.
Guys, this rear was in perfect shape in every way two weeks ago untill they changed the fluid with friction modifier "all ready added" into the new fluid. There isn't $1200.00 worth of worn out gears. Are you all trying to give him a heart attack or what? It's just a little chatter.
Yea your right, that's where it started LOL...I think he'll be fine with a fluid change :D
GreekGod
03-28-2010, 10:37 AM
Guys, this rear was in perfect shape in every way two weeks ago untill they changed the fluid with friction modifier "all ready added" into the new fluid. There isn't $1200.00 worth of worn out gears. Are you all trying to give him a heart attack or what? It's just a little chatter.
That is new info, not in post #1. Guspech750 reported unspecified rear diff noise. No mention was made of chatter. I cautioned about some known complications. Is it better to know about common problems ahead time?
When I installed a new diff., I didn't even know they made a Detroit Locker for the 8.8".
============================== =============
justbob
03-28-2010, 11:43 AM
I though he had linked his post from a couple days ago further explaining the situation. I see now that he didn't. My bad.
http://www.mercurymarauder.net/forums/showthread.php?t=61302&highlight=gear
LeoVampire
03-28-2010, 12:15 PM
That he had gone to a place to have the fluid changed in the rear end and they used something that was supose to have friction modifier in it instead of actualy adding some with the new fluid.
Chances are when it is looked at again all will be fine and this time with an actual friction modifier added his problems will go away seeing this just happend.
Powered by vBulletin® Version 4.2.5 Copyright © 2025 vBulletin Solutions Inc. All rights reserved.