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np208 seals blown out

jfabert

jfabert

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South Ogden, Utah
My tcase decided it didn't want to hold fluid any more while on a 300 mile trip. Stopped to get some gas and noticed atf every were. I still need to find out what seal went to crap but I'm thinking the input. It was a qt low when I filled it up. How likely am I to have burned up bbearings or something else during he trip. It wasn't making any unusual noises. What should I look for when I pull it to replace the seals and is there any other items I should replace while its out? Thanx.
 
jfabert said:
My tcase decided it didn't want to hold fluid any more while on a 300 mile trip. Stopped to get some gas and noticed atf every were. I still need to find out what seal went to crap but I'm thinking the input. It was a qt low when I filled it up. How likely am I to have burned up bbearings or something else during he trip. It wasn't making any unusual noises. What should I look for when I pull it to replace the seals and is there any other items I should replace while its out? Thanx.
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Whats a quart low? You know the thing only takes 2.5 qts right not 5 like the fill hole would suggest.
 
Where did you notice the ATF coming from? Should be apparent enough to track back from your ass end. Is your tranny pan loose/leaking? Does it start at your D L?
 
A quart low is.... I put a quart of ATF in it and that is when it was full to the bottom of the fill hole.

I have not been able to inspect it more closely but when I was under the truck it was coming from the front half of the t case. Also has fluid on the under side of the body too above the front half. I looked at the tranny and did not find any place it would have been leaking from and the fluid full. The rear output has always leaked a little but that was not where this was coming from.
 
jfabert said:
A quart low is.... I put a quart of ATF in it and that is when it was full to the bottom of the fill hole.

I have not been able to inspect it more closely but when I was under the truck it was coming from the front half of the t case. Also has fluid on the under side of the body too above the front half. I looked at the tranny and did not find any place it would have been leaking from and the fluid full. The rear output has always leaked a little but that was not where this was coming from.
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Like I said you over filled it. It wasnt low to begin with. You do not fill an np208 or np241 until it comes out of the fill hole. It takes 2.5 or 2.8 quarts depending on the manual/book you reference.

The extra pressure probably blew out your slip yoke seal or front output seal. Ive personally had it happen to me. Most every complaint about slip yokes sucking and throwing fluid is because people overfill them and theres too much pressure in the case.

Infact when i had my 208 rebuilt (when I learned this) I over filled it the slip yoke seal was brand new and all the extra fluid pushed out the front output.
 
Really the only place on the front portion that would leak and throw fluid all over as you've described would be the front output seal. Easy enough to remove the driveshaft, remove the flange, remove the old seal, install a new seal, install and torque the front flange. Just as easy to replace the rear output seal as well.
 
4X4HIGH said:
Really the only place on the front portion that would leak and throw fluid all over as you've described would be the front output seal. Easy enough to remove the driveshaft, remove the flange, remove the old seal, install a new seal, install and torque the front flange. Just as easy to replace the rear output seal as well.
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It'll just do it again if he puts 5 quarts in it though...
 
I'm not sure where you heard that you don't fill a 208/241 to the bottom of the fill hole. My trans guy says that is EXACTLY where it needs to be filled to and that it where mine is currently filled to with no issues for the last 10 years. Now if the vent is plugged then no matter how much fluid is in there it will start blowing out of all the seals as pressure builds up.
 
I have never had this happen before and I have been filling my 208's to the bottom of the fill hole over the last 10 years. My Chilton manual says to fill with 6 pints(3 quarts) So up to the bottom of the fill hole is around 5 to get it to that point? I will also check the vent to see if its plugged.
 
Well...................I was able to check it out after work and............ what kind of damage can come from driving it 300 miles at about 70mph with the t case in 4 high and the hubs unlocked? I have been gone for two years playing army and the wife has been driving it with the kids crawling around in it. Must have got knocked into 4 high some how. when I came back we loaded up the truck and drove to the new house. didn't notice it was in 4 high but this makes since why it was kinda bogged down a little. It looks like from the oil spots it must have over heated and blew out the breather. Im still going to replace the output seals.oops
 
My guess would be the trans overheated and puked where the tube goes into the case. Have you checked the trans fluid? And don't ask why I have this theory. And I agree with Scott on the proper amout of fluid.
 
I did check the trans after I filled up the t case. It was fine. The body has oil on it right next to the t case breather and back from it. I do need to put a longer peice of hose on it to get it up in the engine bay. Never noticed it ws only a couple inches long
 
I don't think there is any concern with having run it a quart low for a while. The Dodge 208s are always filled a little lower than that. I would just focus on why it puked. You should be able to drive on the highway in 4HI for extended periods, hubs locked or not. It's probably easier on the Tcase for the hubs to be open, since there is no binding.

My first guess would be a plugged breather, but you said the oil was coming from there. How about this theory: It WAS plugged, but enough pressure built up to clear it, which is when it puked? I would expect oil from the input/output seals as well, though.

Something else to think about is that extended running with the shifter in an "unknown" position could have put some wear on the shift forks.
 
It does look to have came out the front output seal also. I bet the vent was plugged because of how short the hose was and the amount of mud packed around it. I'm going to replace both output seals and clean out the vent and replace with a new hose. Thanx for the help in my moments of dumbassedness.
 
4X4HIGH said:
I'm not sure where you heard that you don't fill a 208/241 to the bottom of the fill hole. My trans guy says that is EXACTLY where it needs to be filled to and that it where mine is currently filled to with no issues for the last 10 years. Now if the vent is plugged then no matter how much fluid is in there it will start blowing out of all the seals as pressure builds up.
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Ditto.
 
Im a transfer case re-builder and we tell everyone to fill em up to the bottom of the fill plug. Now if it overheated it will boil fluid out of the breather. And if it gets reallly hot it can burn up the seals and make fluid run out everywhere.
 
My 208 puked on me during my front diff break-in. Never ran 4hi at high speed before. Went maybe 4 miles at 45 mph and I heard a whine as I slowed down in the parking lot. Jumped out to take look and fluid was pouring out.I let everything cool down and checked the fluid, when I removed the plug it it poured out a good bit. This had me puzzled since I always fill it to the fill hole. Still don't know what happened there but the case seems to work fine.
 
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