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Blew Diff seal 03 Cobra

  • Thread starter Thread starter mode03Cobra
  • Start date Start date Sep 11, 2008
M

mode03Cobra

New Member
Sep 11, 2008
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Sep 11, 2008
#1
  • Sep 11, 2008
  • #1
I blew the rear diff seal out of my 03 Cobra Svt with IRS. I wanna know if I have to drop the pumpkin to replace this or just pull the cover seal and fill? If I do need to drop the pumpkin out is there a step by step manual or pdf for this. This will be the first time I would do on IRS cars. My second question is what will I need to do to replace the rear axle seals. I now have the mufflers and tubing off the car and am anxious to do it so any quick help for be great....
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 12, 2008
#2
  • Sep 12, 2008
  • #2
Actually sooner or later the seal on all 03/04 Cobras will leak. It's because of the added torque applied to the housing/cover from the torque brace.

You won't have to drop the housing out completely, but you may need to pull the exhaust out of the way. I HIGHLY suggest that if you are going to remove and reseal the diff cover that you also purchase an aftermarket diff cover brace. This will spread out the torque applied to the diff housing and prevent future leaks. You can get one here:

IRS Brace



U.M.
 

03SONIC

New Member
Sep 12, 2008
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Sep 12, 2008
#3
  • Sep 12, 2008
  • #3
It is easier to just drop the pumpkin to be honest with you, they all leak at one point and time, there is no gasket only sealant.
 
M

mode03Cobra

New Member
Sep 11, 2008
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Sep 13, 2008
#4
  • Sep 13, 2008
  • #4
Thanks guys....Do you have step by step how to drop it since this would be the first time I worked on IRS? Thanks..
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Sep 13, 2008
#5
  • Sep 13, 2008
  • #5
I have a reuseable seal on mine.very easy to change.here is what i did. I have 2 drive on ramps . Homemade buried in my driveway.no jack needed ,car is on all 4wheels.back car on ramps,remove tail pipes,driveshaft.loosen the 2 nuts on front crossmember,then remove the 2 front of diff bolts than the rear 2 bolts on diff cover The rear should move forward enough to remove cover.if front crossmember needs to come out loosen bolts going cotrol arm till crossmember comes off
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Sep 13, 2008
#6
  • Sep 13, 2008
  • #6
Also fuel filter is above diff cover do it now
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 13, 2008
#7
  • Sep 13, 2008
  • #7
hotcobra03 said:
Also fuel filter is above diff cover do it now
Click to expand...
Great point!!!

U.M.
 
M

mode03Cobra

New Member
Sep 11, 2008
6
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0
Sep 20, 2008
#8
  • Sep 20, 2008
  • #8
THANK YOU.....

hotcobra03 said:
I have a reuseable seal on mine.very easy to change.here is what i did. I have 2 drive on ramps . Homemade buried in my driveway.no jack needed ,car is on all 4wheels.back car on ramps,remove tail pipes,driveshaft.loosen the 2 nuts on front crossmember,then remove the 2 front of diff bolts than the rear 2 bolts on diff cover The rear should move forward enough to remove cover.if front crossmember needs to come out loosen bolts going cotrol arm till crossmember comes off
Click to expand...

Thanks man ..... I took the exhaust off and took the drivershaft off. Unbolted the diff and slid it towards the front of the car. I resealed the cover and all is good. Oh yeah and I replaced the fuel filter as well. I really appreciate the tips. Ford was going to charge me 1000.00 to do it. I saved 800 bucks.....
Thanks again.NO MORE LEAKS
 

hotcobra03

Active Member
Nov 29, 1999
969
4
39
poteet,tx
Sep 20, 2008
#9
  • Sep 20, 2008
  • #9
Glad to hear that worked out for you.ive mastered long tube headers but that info would cost you lol stang net rocks
 

03SONIC

New Member
Sep 12, 2008
16
0
0
Sep 23, 2008
#10
  • Sep 23, 2008
  • #10
mode03Cobra said:
Thanks man ..... I took the exhaust off and took the drivershaft off. Unbolted the diff and slid it towards the front of the car. I resealed the cover and all is good. Oh yeah and I replaced the fuel filter as well. I really appreciate the tips. Ford was going to charge me 1000.00 to do it. I saved 800 bucks.....
Thanks again.NO MORE LEAKS
Click to expand...

Wow that is high, I am a Ford dealer and charge half that. For the price you have above, I would also do gears 3.73, 4.10.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 24, 2008
#11
  • Sep 24, 2008
  • #11
03SONIC said:
Wow that is high, I am a Ford dealer and charge half that. For the price you have above, I would also do gears 3.73, 4.10.
Click to expand...
Replacing the stock 3.55's with 3.73's doesn't make a whole lot of sense on the 03/04's really because the difference is so small. Plus the 03/04's have so much torque as it is they blow the rear tires off even under moderate acceleration with just the stock 3.55's. Unless you're a full time drag racer and you want to make sure your RPM's are at max in 4th gear when you go through the traps, then by all means upgrade to 4.10's, otherwise just stick with the stock 3.55's.

Mode03cobra - You'll be sorry for not adding that torque brace I recommended... I'm betting within a year or so and depending on how hard you drive the car, you'll be replacing that diff seal again.

U.M.
 

03SONIC

New Member
Sep 12, 2008
16
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0
Sep 24, 2008
#12
  • Sep 24, 2008
  • #12
Uncle Meat said:
Replacing the stock 3.55's with 3.73's doesn't make a whole lot of sense on the 03/04's really because the difference is so small. Plus the 03/04's have so much torque as it is they blow the rear tires off even under moderate acceleration with just the stock 3.55's. Unless you're a full time drag racer and you want to make sure your RPM's are at max in 4th gear when you go through the traps, then by all means upgrade to 4.10's, otherwise just stick with the stock 3.55's.

Mode03cobra - You'll be sorry for not adding that torque brace I recommended... I'm betting within a year or so and depending on how hard you drive the car, you'll be replacing that diff seal again.

U.M.
Click to expand...


3.73's make a noticeable change, we have done over 50 sets and all the customers feel it and love them street or track. As far as blowing the tire off, anyone running stock tires needs a reality check.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 24, 2008
#13
  • Sep 24, 2008
  • #13
Your ass meter is better than mine if you can feel a noticeable difference between 3.55's and 3.73's! What are we taking about here... 0.05 % difference??? Why even bother?

U.M.
 

03SONIC

New Member
Sep 12, 2008
16
0
0
Sep 24, 2008
#14
  • Sep 24, 2008
  • #14
Uncle Meat said:
Your ass meter is better than mine if you can feel a noticeable difference between 3.55's and 3.73's! What are we taking about here... 0.05 % difference??? Why even bother?

U.M.
Click to expand...

On my own car I picked up .02 tenths, same tire, same everything. No ass meter,exit only.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 24, 2008
#15
  • Sep 24, 2008
  • #15
Oh I do not doubt there's a measurable difference! Your .02 tenths proves it. I just don't see the value in it for a street driven Cobra. The OP on this thread has over 200,000 miles on his car currently... I'd say it's a daily driver and not a track car.

U.M.
 
M

mode03Cobra

New Member
Sep 11, 2008
6
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Sep 25, 2008
#16
  • Sep 25, 2008
  • #16
ACTUALLY...

I only have 28,000 miles on my car and its not a daily driver its not a tracker either. Its something that I bought to piss off all the ricers around town.
 
U

Uncle Meat

Banned
Jun 13, 2002
0
1
0
Prattville, Alabama
Sep 26, 2008
#17
  • Sep 26, 2008
  • #17
mode03Cobra said:
I only have 28,000 miles on my car and its not a daily driver its not a tracker either. Its something that I bought to piss off all the ricers around town.
Click to expand...
My bad man. It's hot03cobra who's car has over 200K on the odo!

U.M.
 
M

mode03Cobra

New Member
Sep 11, 2008
6
0
0
Oct 2, 2008
#18
  • Oct 2, 2008
  • #18
No worries U.M....You guys rock either way for helping me with the diff seal. I made the ultimate test too. I drove the car around normal after everything and then i put the car back in the garage. I put a new grease getter on the ground to see if any oil was leaking. No leaks. Then I pulled it out and burned a serious strip up the road to put some rubber to the road and all is well. No drips. I did the fuel filter too. Good looking guys now the when I put on the long tubes I will come to you and hotcobra03 and 03sonic....haha. thanks again guys.:SNSign:
 
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