Sorry if this sequence is a little tarantino'd

Car; 2006 Evo IX

Relative Mods/recent activity: Replace inner CV boot on passenger side. Done by me.

Spotted: the next day by dealership while performing ACD fluid change and Transfer case fluid.

Solution: Dealer Replace both axle seals. I know the driver side leak was there. Unaware of the transfer case axle seal leak.

Still: leaking from transfer case seal.

My first guesses: I banged something up removing the passenger axle while repairing the CV boot. I dont know what or how I did anything, but Im here to find that out. I have seen a basic diagram of seals and parts in the transfer case, could I have banged an inner seal? But wouldnt an inner seal leak ACD (trans fluid) and not gear oil correct? The fluid I leak is tansfer case and not ACD type. Currently there is redline shockproof in there, however prior to this I had some BG, 75-140, and yeilded the same leak.

. When I picked my car up at the dealership I noticed a large dinner sized plate spot of gear oil under teh x-case. I suggested I wont drive it far and topped it off went home did a little research. I came across some advice from Shep, and he stated that the t-case axle seal could be pushed in too far. So sure enough, I check and its in there crooked.. Very plainly crooked. I instantly go back to the dealership, and ask the tech personally to double check everything. I did this politely, and he complied we disassembled everything, reassembled the t-case seal in a more proper fashion. He had me scope it out before resassembling. I viewed it as a better result than the last time. Reassembled the car, drove it on the lift for some time. Reinspected the seal and no leak was visible. I thought I was good to go, and tada went off


Summary: leaking as I type. less than a dime sized spots every half hour-hour approx. I thought I fixed it the second time around. the dealer tech did too. He is cool. I am dumbfounded.

What is there to mess up. It is not clear to me if there was ANY sort of leak prior to me doing the CV boot. If there was it was small, If there wasnt , i couldnt gaurantee that. enjoy. suggest. critique To my knowledge the same seal was pulled and reused.

 

Those seals are very finicky. Those things basically slide in with hardly any effort, which seems to me like it wouldn't seal great...but they do sometimes. Getting the perfect installation depth is key on those.
After fixing Audi's for over 10 years and replacing many a seal, it truly surprised me how easily the evo seals went in compared to the Audi seals. It seems as if the seal should be just a bit bigger in circumference.

 

I will be picking up an extra T-case seal and doing the work my own ASAP. What if I got a bad seal? Can/does this happen? The other catch could be the fluid the tech saw leaking was that of which I let leak a bit while I was doing the CV boot. i didnt wipe everything up after out of sloppiness.

 

Probably not a bad seal IMO. What I did was install the seal, but not "all the way" and test fit the axle to see where the axle "cup" was in relation to said seal. Go from there. Without a special tool that would automatically install and stop the seal at certain point, it's a bit tedious to get correct.

 

Done it atleast a dozen times on a subie, Im sure I got the right socket for the job haha... in all actuality we removed the steel debris shield from that axle. We had a hard time fitting the rubber cup/cone into the steel thing, and thought it may be interfereing. it looks as if there is fluid coming from between the xcase and the seal itself. But it also looks like the axle may not be fully engaged by the circmfrence of the seal.

 

Took the plug out, and there was some pressure built up in the gear case. Enough to make a few seconds of hissing noise while unthreading. Normal? Pressure would certainly push something out of a seal like this now wouldnt it?

 

There will be a bit of pressure build up, but there is a vent for that. Make sure the correct seal is being installed...I'm not 100% on this, but I think the tcase seal and trans seals are different part#. Please correct me if I'm wrong.

I know what you mean about the loose fit. After I did mine, I wondered "How the hell does this thing seal anything?" Lol. My assumption on the tight seal is that when that car is running/moving, the oil is being sent around to where it needs to be and is not really putting pressure on the seals. The only time it's putting some sort of pressure on the seals is when it's sitting static. I don't understand the logic behind it, but who am I to say how it should be?

On a side note, after working on German engineered cars for so long and then working on the evo, it's truly amazing the thought that goes into the simple stuff like this.

 

as of now there is def not enough fluid in the case. Going to have to make some action soon, just dont know what else to physically inspect. Its for sure coming from the axle. The axle kind of looks like it is not seated in all teh way, but it did click in place, and the shield is removed.

 

Now, I am even more thoroughly confused... STM replaced the transfercase fluid with Redline heavyweight Shockproof, and the leak I am still seeeing is the neon green color of BG.

Now I have loaded the Mitsu LSD oil after draining the Redline. I believe the redline looked as it should. Kinda pepto'bismol lookin..?

Gonna drain it in a few days and measure volume.

 

Been doing a fair bit of searching. Still nothing quite like this. It seems like its A) a mystery flud B) not actually leaking. Thats my idea of measuring the drain from the T-case in a few days. Poured approx 20oz into the t case. If I wind up with a lot less I guess ll know.

What would a different color flud be leaking out of? doesnt appear to be mixing tcase and trans fluid.

 

asked the tech if he reused the same seal and he did. So I put another new one in today, seems leak free for the moment..

If a transfercase axle seal leaks, transmission gear oil or transfer case fluid will seep?

 

Bump... replaced the seal myself and its still leaking as of two weeks ago . Left it out an eighth too..

 

Are you certain thats where its coming from? Any chance it could be coming from between the T-case and the trans, which is why your noticing BG looking fluid rather than the shockproof you said was in the T-case? I had a TERRIBLE experience like this when I installed my Wavetrac LSD, the first 3 times it was because I was sent a bad LSD, tolerances were off so it wouldnt let the stud shafts lock into place.

Can you take a picture of the axle installed into the seal so we can see how it looks? I had a problem with one of my half shafts being a little messed up. The end where the c-clip goes was a little worn and it wouldnt let the clip fully lock into the diff when it was installed. This caused about 3-4mm worth of "slack". So since the axle locked onto the stub shaft and the stub shaft had a little play, it cause the axle to slide in/out a few mm's while driving, so the axle would be riding the seal one moment, then not the next (causing a leak) back and forth back and forth. I finally replaced the stub shaft and all was well.

 

100 percent sure its dripping right out of the seal. I dint set the seal in as deep this time. I occasionally smell oil burning off the dp. Haven't checked the level lately so there might not be enough to leak out anymore . At the same time maybe I did fix it and have been perpetually over filling

 

Damn this **** makes u wanna just burn the thing and collect insurance lol.but yea the half shaft not being fully engadged into the diff sounds like a good argument.I've never changed one on a evo bjut I know most cars I've done I really had to forcefully insert it into the trans/T case. Like vtec said it most deffantly would be leaking if the seal wasn't seated correctly on the machined part of the shaft.