Gaskets are made of paper and have NOTHING to do with inducing IRS movement. It's all about the bushings and using the right subframe bolts as well as traction to stop the IRS from moving around.
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MY rear end is leaking! Question for all of you
- Thread starter drusmith
- Start date
I did something VERY unconventional to get my IRS to quit leaking.
I figured that I would try it and worst case scenario it would still leak.
I in the past had been running my car at local track nights and track day events; my rear end had been dripping oil on my driveway and I was just about to pull the trigger and buy a LPW cover when I was sitting at work one night and it hit me. The way the differential flex's under twist, the seal between the cover and the rear end brace gets pulled apart. It at the time made sense to me to just make a bead of silicone and run it from one side of the cover to the other on the bottom of the cover where the cover bolts to the differential housing.
That was over a year ago; me using it as my DD and racing it at several track days (1.56-1.59 60ft.s)
It's still not leaking :burnout:
I figured that I would try it and worst case scenario it would still leak.
I in the past had been running my car at local track nights and track day events; my rear end had been dripping oil on my driveway and I was just about to pull the trigger and buy a LPW cover when I was sitting at work one night and it hit me. The way the differential flex's under twist, the seal between the cover and the rear end brace gets pulled apart. It at the time made sense to me to just make a bead of silicone and run it from one side of the cover to the other on the bottom of the cover where the cover bolts to the differential housing.
That was over a year ago; me using it as my DD and racing it at several track days (1.56-1.59 60ft.s)
It's still not leaking :burnout:
I like your method. Cheap, easy, and effective = WIN!
IRS brace at least?? If not it's really only a matter of time before the cover would crack, "from what I've seen anyway" mine leaked and after taking off and seeing how thin it was compared to the LPW and the better features I'm glad I did it. But hey if it's working don't fix it...
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The only mod my IRS has is the Billetflow brace.
My question is will a small leak or seepage turn into a big problem? I have the BF brace on mine. Last year when I had my car up on the rack my mechanic pointed out the small leak to me or i would of never known. The shop quoted me $400 to reseal diff + cost of axle seals which surprised me how expensive it is! Plus throw in the cost of the LPW Cover and I'll have over $600 in this job. How important is this to fix if it's just a tiny seep of oil? Can I put if off for awhile?
It can, you are losing differential fluid so check the level. Do you see drips underneath the car when you park?
Sounds about right, not an easy job because the whole differential has to come out. I highly recommend the LPW and the lubelocker gasket. Solved my leak problem.
As long as you don't let the differential fluid get low and you keep checking it FREQUENTLY - you should be good.
Mine leaked for a while too but after seeing some people shatter the cover and the mess it made I figured why not, and my girls dad has worked on mustangs forever so I laid on my back for eight hours and did that and the bushings. Never been so tired after that one but it was worth it.
And it's so easy to change the fluid.
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And it's so easy to change the fluid.
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To the OP, there are a few ways to seal the diff.But the real question is why did it start leaking?You have to look in to a bushing kit to "plant the rear" mm or full tilt boogie racing make these kits.I went back & forth for months Gasket-RTV-gasket-RTV! You should be leak free with a thin gasket like that fel-pro.I ended up going with the advice of ford shop manual,LPW directions & full tilt boogie FORD RTV
Then your leak is insignificant.
Six months
Right after someone swapped my IRS cover for the LPW. 30k
Almost never, just keep it filled. The time to correct the issue is when you can get an LPW cover.
I just ordered the same cover and I am wondering if i can take the cover off and swap it without droping the whole thing out? I found this and was wondering if it would work....I have a reuseable rubber gasket to go with it so im not worried about getting the rtv sealer up there without messing it up.
''You have enough room to get the cover off, take out the 4 bolts on the bar infront of the diff. and take out the 2 bolts in back of the diff, remove the drive shaft and push the diff forward remove the bolts on the cover and should have enough room, I did. Shops just say you have to so they can take from your wallet''
My rear is also seeping slightly and my mechanic said to use the permatex gasket sealant along the bottom of the rear. I still might just have the rear dropped and if I do that what else should I have done while the rear is down? i.e. replace all bushings and if so which ones should I replace with? Any help you can give is appreciated. thanks.
ps. I already have a billetflow irs brace on it
ps. I already have a billetflow irs brace on it
I'm literally putting my IRS back together. Mine was out for the same reason diff leaking. I replaced all the bushings to poly, subframe, lower control arm, upper control arm, and diff bushings. Bought the LPW diff cover along with a lubelocker gasket. I torqued the cover to specs along with lockwashers and locktite. I also Upgraded the tie rods to the thicker upgraded Hiem joints along with sway bar Hiem joint links. Get the tools to remove the bushings or a small butane torch to get em out. It's a pita, get friend to help. Good luck
Unfortunately you'll likely be going back and replacing all those poly bushings again, as there really not much better than the stock rubber ones. Poly ones can also melt from to much heat especially the diff bushings. Delrin is the best for bushings, the rest of your list looks good.
hey bro, i got the same car as you and of course, my diff was leaking when i bought it. check this out, and it only had 10k miles on the car! i thought it wasent a big problem. so i pushed it off for 3 months. i decided to put some motorcraft gear oil in the diff to see how much has leaked out u know. it took a half a quart, not bad. about 3 months later, everywhere i went when i backed out of parking spots i noticed a little more drip on the ground. so i knew things were getting a little worse. and around that time i started hearing a noise coming from the rear, it was only noticeable when i pointed it out. best way to describe it was, a mouse chewing on a piece of wood.. so i decided to fill my diff again with gear oil i got from ford, it took another half quart, still not bad. but the noise didnt go away..so i knew i had a real problem..a friend of mine and i tore down my end and took out the pumpkin, we opened it up and examined. we found that the carrier bearings went out and there was scorn marks all along the rollers..and i forgot to mention, both times i refilled my oil there was metal shavings on the back of the fill plug..so i ordered, new 355 ford racing gears, the lpw diff cover, and the master bearing kit from steve at tousley. then dropped it off at a local gear shop and they put it all back together for me and set the gears and my friend and i just put it all back together..what sucks is, in the process of all that i nicked my cv boot on something and the grease is coming out and the bearings are making noises. need a new half shaft now..just doesnt end..goodluck with the differential leak. its not as bad as u think. oh and btw they sealed it up with ultra black rtv. i also went to the track 3 weeks ago and made 9 passes, still holding up..i also decided to change my front and rear diff bushings from full tilt boogie racing. delrin bushings. without the bushings, it was about $800 for me...GL!
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This sounds good but it is really BS in my experience. I have had poly bushings in my rear ala MM IRS GRIP BOX for years and have never had a problem. I've run my car on a road course more than once, drag strip only once and have carved the mountain roads, in spirited fashion, in WV for years with my set up and not a single issue..............not one! Don't believe the guys that tell you "oh poly bushings aren't much better than stock", not true. My set up really made the car feel more solid and would recommend to anyone wanting to improve the strength of their rear end, also no noticeable difference in sound from the rear either.
I want to hear from one guy who has had their poly bushings melt? My next question is describe the driving activity prior to bushings melting. I'm gonna get a beer now.
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Can u let me know exactly what I need to buy as it relates to the busing kit(s). I want to make sure I do the job once and upgrade everything while the IRS is down. Also let me know the best place to buy the parts. Thanks in advance.
id say go to fulltiltboggieracing.com and check out what hes got.
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