Do you know where that bolt is, I am new to this car, but learning very quickly, is there a picture with words to show you where things are?
2003 SVT Cobra Differential Leaking???
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Do you know where that bolt is, I am new to this car, but learning very quickly, is there a picture with words to show you where things are?
I'll have to do some digging, I'm sure there's pictures somewhere. Here's a link from FTBR showing some locations of bushings and diff cover. So far I've had great luck with my diff cover not leaking. I have a LPW cover (similar to Ford racing) which has been out way longer than the ford racing unit. It cost less and get's the job done. I added FTBR front and rear bushings. This was done on my car about 2 yrs ago.
FTBR IRS Bushing Locations
A new differential cover/resealing the cover is going to stop the leaking. The brace helps support the differential cover. The brace isn't necessarly going to stop it from leaking again because the IRS system has so much flex. The brace will prevent your entire differentials from blowing out through the cover.
No matter which route you go, reseal with a brace or replacing the cover make sure you replace the front and rear diff bushings with either the FTBR or MM polyurethane bushings. Talk to Bruce at FTBR and he will guide you in the right direction but isolating the diff will reduce the flex or twisting and subsequently the leaking.
I went though this exact problem a couple years ago. I was replacing my clutch and noticed the diff leaking while I had it apart.
Here's what I did:
Remove the rear exhaust cat-back.
You basically have to take the entire rear IRS apart. Unbolting both the rear uprights to remove the axle shafts and allow you to get the Differential out. There are a few here that have 'cheated' and were able to replace the cover without totally removing it, but I preferred to put it on a bench to to a better job of cleaning it off and getting a good seal.
I replaced the front subrame bolts with 9/16" bolts from Ace hardware. They were a PITA to get lined up, but fit better than stock. Used a come-along to get the subframe lined up enough to get the bolts in.
I replaced the IRS bushings with Max-motorsport poly bushings. I know the FTBR kit is 10x better, but I was in a hurry and already had the MM set onhand. Not as good as FTBR, but much better than stock. IMHO.
IMHO, the 'billet-flow' style brace just seems like a band-aid and will not do much to prevent future leaking. And for just a little more cash, you can upgrade to a FRP or LPW cover. I went with the LPW cover. IIRC, it was only $180 which is quite a bit less than the FRP cover. The LPW cover is a very nice piece of hardware. The only issue is you will need to grind down the cast "LPW" logo on the back, because it interferes with the rear mount bracket. Not a huge deal, and you cant see it anyway.
**I also installed a remote vent tube for the diff vent. We get a ton of rain in FL and it was super easy to move the vent up another 8-10" away from the road.
**Fuel filter is super easy to replace while the diff is out.
All in all, I rate this as about an 7/10 difficulty when working on jack stands. Probably the worst part for be was getting the lower control arm bolts lined back up when bolting the diff-support cross member back in.
Here's what I did:
Remove the rear exhaust cat-back.
You basically have to take the entire rear IRS apart. Unbolting both the rear uprights to remove the axle shafts and allow you to get the Differential out. There are a few here that have 'cheated' and were able to replace the cover without totally removing it, but I preferred to put it on a bench to to a better job of cleaning it off and getting a good seal.
I replaced the front subrame bolts with 9/16" bolts from Ace hardware. They were a PITA to get lined up, but fit better than stock. Used a come-along to get the subframe lined up enough to get the bolts in.
I replaced the IRS bushings with Max-motorsport poly bushings. I know the FTBR kit is 10x better, but I was in a hurry and already had the MM set onhand. Not as good as FTBR, but much better than stock. IMHO.
IMHO, the 'billet-flow' style brace just seems like a band-aid and will not do much to prevent future leaking. And for just a little more cash, you can upgrade to a FRP or LPW cover. I went with the LPW cover. IIRC, it was only $180 which is quite a bit less than the FRP cover. The LPW cover is a very nice piece of hardware. The only issue is you will need to grind down the cast "LPW" logo on the back, because it interferes with the rear mount bracket. Not a huge deal, and you cant see it anyway.
**I also installed a remote vent tube for the diff vent. We get a ton of rain in FL and it was super easy to move the vent up another 8-10" away from the road.
**Fuel filter is super easy to replace while the diff is out.
All in all, I rate this as about an 7/10 difficulty when working on jack stands. Probably the worst part for be was getting the lower control arm bolts lined back up when bolting the diff-support cross member back in.
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Wow that does look hard, I don't have any car jacks so I might have to get one or go to the shop to get it fixed, don't want to do that because it costs a lot more.:??:
There has been members on here posting pictures of blown diff covers WITH a brace on!
So that means Brace= extra weight= NO:coolman:
Exactly this minus the brace part. The brace isn't for leaking as much as blowin your differentials out during a launch or hard take offs. Look up videos or pictures of people who have blown them out. Not pretty lol
Why do cobra IRS have so many leakage problems? Because the thin, weak stock cover flexes too much causing the seal to leak. Less flexing of the rear cover should improve leakage problems.
The LPW and FRP covers solve several problems.
>Stronger, thicker cover will reduce flexing
-less wheel hop
-less leakage
-less chance for a total failure with hard launches
-has drain hole
-has bearing cap supports
-The FRP unit has bosses for cooling lines.
I may need to swap those out. Is there much to it?
I did it when I had the exhaust off and the IRS mostely apart. It might me a PITA if you had to work around the exhaust.
The subrame and the frame holes do not like to line up. Rumor has it, thats why Ford took a short-cut with the 12mm bolts.
I used a come-along to pull the subframe into alignment.
What is the fluid capacity? What weight and how much friction modifier? Does anyone have a link to a thread with a how to on just dropping the pumpkin? I'm not wanting to remove the whole IRS from the car.
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This is how to remove the IRS, don't worry it should be the same process as this 1999 cobra.
pumpkin
pumpkin
Fluid capacity is 1.5 qts - I use Royal Purple that has friction modifier in it so I'm not sure of the capacity of that.
Just did this a couple of weeks ago to have my diff rebuilt:
1) Remove rear wheels
2) Remove catback using some WD40 on the exhaust hangers
3) Remove driveshaft from flange using 12mm 12-point socket/box wrench
3b) tie strap driveshaft to bottom of car to keep it out of the way without removing it from the trans
5) Remove brake caliper/brake caliper bracket/rotor (probably going to need to remove e-brake cable - pretty easy - remove e-clip with needle nose pliers and use vice grips to pull cable out of the spring-loaded quadrant - be sure e-brake is down)
4) Unbolt inner tie rod ends
5) Unbolt lower control arm to spindle bolt
6) Use a long screw driver or similar tool to gently pry between ABS ring and pumpkin to release the axle
7) Unbolt camber bolt (upper control arm to spindle) and gently pull out axle being careful about not hitting the inner splines on anything - this can be easier with a second set of hands but is definitely possible by yourself (ask me how I know)
8) Loosen front differential mount bolts
9) Loosen rear differential mount bolts from rear diff mount
10) Place jack under pumpkin (could be done earlier depending on if you feel like its in your way or not)
11) Remove NUT of front lower control arm to subframe/front diff brace on both sides (***do not remove bolt from control arm - you need at least a few threads sticking out otherwise you could damage the car or kill yourself if the spring decides to come loose) This will make it easier to remove the diff brace and unbolt the front diff mount
12) Unbolt front diff mount and rear diff mount
13) CAREFULLY lower the jack while keeping a hand or two on the pumpkin to make sure it does not tip off since it is not well balanced - another time a second set of hands would be useful
It's possible I forgot something but that should be the basics
Helpful videos here: FTBR Informational Videos
^^Pretty good step-by-step
I would add a couple minor points:
> Use a fine tip paint marker to mark the position of the upper eccentric (alignement) bolts. You really should have your alignment checked after this, but this will give you a decent reference so you will at least be streetable when its all back together.
>Don't torque downe the LCA bolts until you have the car on the ground with all the weight on the springs. Otherwise you will have some pre-load on the rubber LCA bushings. It will affect the ride height and tear up the rubber bushings.
I would add a couple minor points:
> Use a fine tip paint marker to mark the position of the upper eccentric (alignement) bolts. You really should have your alignment checked after this, but this will give you a decent reference so you will at least be streetable when its all back together.
>Don't torque downe the LCA bolts until you have the car on the ground with all the weight on the springs. Otherwise you will have some pre-load on the rubber LCA bushings. It will affect the ride height and tear up the rubber bushings.
Finally got this fixed. The cover was leaking before so the previous owner decided to seal it up. Well, he did not remove all the oil in the differential, so the silicon glue did not stick to the cover, instead to the oil. So that is how it still leaked, later i took the car to a friend of mine and he fixed it. 
FRPP cover and ARP hardware with Lube locker gasket. It will never leak or break.
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