Leaking output shaft seal

[Meanwhile]

I noticed the other day that under the output shaft on my front drives was a little wet, an obvious leaky seal. I got the parts needed but nobody local can get me in until September. Is this something I can do without an impact? I’m guessing probably not but thought I’d ask anyway.

[Chamberpains]

Not without a torque multiplier for your ratchet. Also be prepared to put a new yoke on it too if this is a high mileage truck. The seals have a tendency to wear a groove in the yoke.

[Meanwhile]

Thanks! I didn’t think I’d be able to do it myself right now. I’ll probably get a yoke too since it’ll be coming apart and avoid getting it done again sooner than necessary.

[JMBT]

Meanwhile: it is not a terrible job, but you will definitely need a large impact or as stated above a torque multiplier. Also a yoke puller makes the job a lot easier.

***However, are you positive that it is actually leaking?? What kind of rear end is it? I have meritor MT40’s. I downloaded the service manual when I replaced mine and the first few pages were dedicated to determining if a slightly wet spot around the seal indicates a leak. On a meritor rear end the input and output shaft seals come from the factory with a red grease in lines on the inner diameter of the seal. At some point in the life of the seal it will get warm enough to melt the grease and it can look very much like a leak.

The jist from the Meritor manual was it is not a leak until an oil trail can be observed running down from the seal. Slightly wet around seal or damp is probably just the melting grease.

[Meanwhile]

Thanks JMBT, mine is definitely leaking. I’ve been checking it and adding oil the past couple days. Looking at that seal, it looks like a larger version of the ones on my pickup. Normally I’d attempt it but I don’t think my tired old air compressor could do the job. I can’t justify buying a new compressor and impact right now though I’d really like to. I’ll figure something out over the next couple days. Thank you all for your input and assistance here on this forum.

[kozakvod]

(08-22-2020 )Meanwhile Wrote:  Thanks JMBT, mine is definitely leaking. I’ve been checking it and adding oil the past couple days. Looking at that seal, it looks like a larger version of the ones on my pickup. Normally I’d attempt it but I don’t think my tired old air compressor could do the job. I can’t justify buying a new compressor and impact right now though I’d really like to. I’ll figure something out over the next couple days. Thank you all for your input and assistance here on this forum.

I bought this TRQ MLT a couple years back and it is great. Used it in many different situations. I don't have access to any air beyond what my truck provides so to have certain tools were great spends of my $'s. https://www.northerntool.com/shop/tools/..._200623947

Not to mention this great impact would be a crime. And yes, it will remove wheel fasteners. https://www.northerntool.com/shop/tools/..._200684083

[Rawze]

Most rear axle yoke nuts are in the range of 800 to as much as 1270 ft-lbs on some of them. A person should have a proper tool that is designed to go this high ... look it up in the service manual for the proper spec to be sure.

here is a really nice puller for yokes, etc... and such. It also is just big enough to fit onto the crank shaft damper of an ISX and pull it.
https://amzn.to/3grh5Oy

arms can be flipped to pull inner races of hub bearing too.

[flatbed94kid]

I changed mine myself and it leaked again. Then hired some guys to do it and it leaked again!!!
What they did to get that nut loose is they used a torch to heat up the nut. Then a long breaker bar and pop it was loose. A good hot torch is your friend here.

You want to change the yoke as well bc the old one often wears a pattern in the old yoke seal like Chambers said and with a new seal it will leak again. Some reuse the big nut, some don't. Probably should add some red lock tite to it as well

My suggestion, get someone to do it.Unless your Rawze or Chamberpain.

Waterloo knows a guy who said there is a crush washer also. Was the reason why his was leaking. Also if your u-joints are pressed in they could be hard to pop loose. May change that u-joint while your at it or just check all the other joints as well. All new Driveline time! fun fun!

[Meanwhile]

Thanks for the links and all the information. I'm gonna bookmark the links for possible future purchases. There are times where it's difficult to wrap my mind around things like these new battery powered impacts that have high enough torque to remove these type of things. I'm gonna have to look into it I guess.

I found a shop that can get me in Wednesday to change the seal. I bought the seal, U-joint, strap kit, flange nut (they said there is no washer for this one) and the yoke. Even though I was told it's not leaking that badly, I just want it done. The past few days I've added 6-10 ounces of oil about every 650 miles.

Thank you all for your input!