2005 Rubicon; A Rubi Brother

Well guys. Just got home from picking up my Jeep from the gear shop and running errands. Man this thing just absolutely glides at 70mph. There’s such a difference in the performance and I’m so glad it’s finally done. 5.13s are recommended on 33s but I’m sitting on 32s so it’s just the right amount of gear I think. Can’t wait to use it off road for the first time but I have to finish the break in period :(

Also big thanks to @PRNDL for selling me a Speedo Healer that’s been sitting in my closet for a year lol. It’s finally being used, and working!

All eyes are on you Sir. We will be doing some wheeling soon.
 
Well guys I decided before I spent a grand on getting the rear main seal replaced, I’d take one more swing at it. It’s dripping pretty bad at this point.

One of the guys in my church has worked for the Chrysler parts department for years, and works with a guy at the local dealership that’s been a Mopar master tech for the last 25 or so. The tech gave me some good pointers on how to successfully perform this job, and I’ll do my best to share those details when I decided to tackle it.

If not, I’ll just take it to him to fix 🤣
 
Well guys I decided before I spent a grand on getting the rear main seal replaced, I’d take one more swing at it. It’s dripping pretty bad at this point.

One of the guys in my church has worked for the Chrysler parts department for years, and works with a guy at the local dealership that’s been a Mopar master tech for the last 25 or so. The tech gave me some good pointers on how to successfully perform this job, and I’ll do my best to share those details when I decided to tackle it.

If not, I’ll just take it to him to fix 🤣

You can do it I'm sure after the great job you did on the tranny swap.
 
See I appreciate the encouragement. The problem is I attempted to fix the RMS when I did the transmission swap. Here I am again! :(

I think I used the BleepinJeep video as my go by. The one done by the guy that’s no longer on BleepinJeep.
 
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See I appreciate the encouragement. The problem is I attempted to fix the RMS when I did the transmission swap. Here I am again! :(

It was your first time? If so believe me it does take a little bit of practice. I had them leak before too after the first try.
 
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I just watched the Bleepin Jeep video and then read a write up on doing the RM and one thing I was taught to do differently was to offset the split seal just a small amount. I was taught to push in one side maybe 1/4" so that the split part of the seal isn't right when the main cap and block are. The reason for this is that a lot of times the leak is right there where the two halves meet. By them being offset it move that area away from there. You still RVT the heck out of it. I don't know if this is recommended on the 4.0 or not.
 
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See I appreciate the encouragement. The problem is I attempted to fix the RMS when I did the transmission swap. Here I am again! :(

I had to do mine twice...but the second time (with a Mopar seal vs Felpro) is still holding strong after 3+ years. You can do it! Oh, and get the anaerobic sealant...Don't just do the RTV.
 
It was your first time? If so believe me it does take a little bit of practice. I had them leak before too after the first try.
Yes it was and I was close but not quite there. I should have used anaerobic on the main cap but foolishly used RTV instead.

I just watched the Bleepin Jeep video and then read a write up on doing the RM and one thing I was taught to do differently was to offset the split seal just a small amount. I was taught to push in one side maybe 1/4" so that the split part of the seal isn't right when the main cap and block are. The reason for this is that a lot of times the leak is right there where the two halves meet. By them being offset it move that area away from there. You still RVT the heck out of it. I don't know if this is recommended on the 4.0 or not.
He didn't recommend it on the 4.0. The seal is small and frail and you risk damaging it trying to push the two halves together. The only spots RTV needs to go is the line where the crankcase meets the timing cover and where the main bearing cap with the RMS meets the crankcase. The bearing cap gets the anaerobic sealer. That's what I was told anyways.

I had to do mine twice...but the second time (with a Mopar seal vs Felpro) is still holding strong after 3+ years. You can do it! Oh, and get the anaerobic sealant...Don't just do the RTV.
Yes I learned this one the hard way as I used all RTV the first time, but the anaerobic sealer arrived today :) I did bite the bullet and buy the Mopar seal. It seems there's been a big failure rate with Felpro RMS as of late. Still using their oil pan gasket though.

I think I used the BleepinJeep video as my go by. The one done by the guy that’s no longer on BleepinJeep.
I've seen that video. When did you do yours and how is it holding up? I saw him RTV the bottom of the seal and I was trying to figure out how you would get that RTV out of the channel if you ever had another failure. I also cringe when I watch people doing that kind of stuff without gloves.


Thanks for the tips everyone!
 
I've seen that video. When did you do yours and how is it holding up? I saw him RTV the bottom of the seal and I was trying to figure out how you would get that RTV out of the channel if you ever had another failure. I also cringe when I watch people doing that kind of stuff without gloves.
It’s been several years, hasn’t leaked yet.

Good question on cleaning the channel, I don’t remember exactly how I did mine other than I used the mopar anaerobic stuff.

Why do you need gloves?
 
Yes it was and I was close but not quite there. I should have used anaerobic on the main cap but foolishly used RTV instead.
If that is what is being recommended, then use it.

He didn't recommend it on the 4.0. The seal is small and frail and you risk damaging it trying to push the two halves together. The only spots RTV needs to go is the line where the crankcase meets the timing cover and where the main bearing cap with the RMS meets the crankcase. The bearing cap gets the anaerobic sealer. That's what I was told anyways.
The offset is very tiny. I don't think I took pictures of it when I did the one on my engine. Same design but I also had it all apart. I've done the offset on rigs when I was under the rig like you are. It's just a trick I'd learned from others.

I wish you the best of luck and hope it holds this time.
I've seen that video. When did you do yours and how is it holding up? I saw him RTV the bottom of the seal and I was trying to figure out how you would get that RTV out of the channel if you ever had another failure. I also cringe when I watch people doing that kind of stuff without gloves.


Thanks for the tips everyone!

I hardly ever wear gloves when I'm spreading RTV. But I also only recently started wearing mechanics gloves or rubber gloves when doing messy stuff.

You can scrap the stuff out of the channel and brake clean work wonders too. But I'm an OLD school mechanic and learned stuff that isn't allowed now days.
 
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Why do you need gloves?
I hardly ever wear gloves when I'm spreading RTV. But I also only recently started wearing mechanics gloves or rubber gloves when doing messy stuff.

Man, I just sound like a snob now lol. I'm such a baby when it comes to my hands being musical and all so anything I can do to protect them from harm I do. I'm just a very big neat freak in general so I don't like messes, even on me.

The offset is very tiny. I don't think I took pictures of it when I did the one on my engine. Same design but I also had it all apart. I've done the offset on rigs when I was under the rig like you are. It's just a trick I'd learned from others.

I might play around with it and see if I can make it work, I see the benefit for it for sure.

You can scrap the stuff out of the channel and brake clean work wonders too. But I'm an OLD school mechanic and learned stuff that isn't allowed now days.

Brake clean is a miracle cleaning agent. I've also heard lacquer thinner is good for that stuff too.
 
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Yes it was and I was close but not quite there. I should have used anaerobic on the main cap but foolishly used RTV instead.


He didn't recommend it on the 4.0. The seal is small and frail and you risk damaging it trying to push the two halves together. The only spots RTV needs to go is the line where the crankcase meets the timing cover and where the main bearing cap with the RMS meets the crankcase. The bearing cap gets the anaerobic sealer. That's what I was told anyways.


Yes I learned this one the hard way as I used all RTV the first time, but the anaerobic sealer arrived today :) I did bite the bullet and buy the Mopar seal. It seems there's been a big failure rate with Felpro RMS as of late. Still using their oil pan gasket though.


I've seen that video. When did you do yours and how is it holding up? I saw him RTV the bottom of the seal and I was trying to figure out how you would get that RTV out of the channel if you ever had another failure. I also cringe when I watch people doing that kind of stuff without gloves.


Thanks for the tips everyone!

The other thing to watch for is to be careful NOT to cut the seal. I know that sounds silly (like duh, of course you don't want to cut the seal) but its very easy to do and very easy to miss, if you do. Use the little plastic guide in the package. The edges of that bearing cap are VERY sharp and they'll peel just a little shaving off that upper seal when you install it and presto! it will leak on you. I cut one of mine, it just felt a little funny going in, so I pulled it back out and looked at it. Sure enough, I cut a little shaving off.
 
Man, I just sound like a snob now lol. I'm such a baby when it comes to my hands being musical and all so anything I can do to protect them from harm I do. I'm just a very big neat freak in general so I don't like messes, even on me.

You don't want to see me trying to play an instrument or sing believe me. My daughter is always shocked at how I can pick up something hot and not feel it, but I've beat the crap out of my hands. When I joined the Army in 1978, I don't ever remember them offering us any type of gloves while working on things. It wasn't until the 90's that they started to issue us mechanic gloves or rubber gloves for stuff like packing wheel bearings.

I might play around with it and see if I can make it work, I see the benefit for it for sure.

We've all got confidence that you've got this. And you have the support of everyone here so if you run into issues just give a shout out and someone will respond.

Brake clean is a miracle cleaning agent. I've also heard lacquer thinner is good for that stuff too.

Alcohol wipes work good for some of this type of stuff too.
 
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Well I got under my Jeep for something last week and alas, my rear pinion seal was leaking horribly. Decided it would be easier to do myself than to schedule a time to take it back to the shop and have it replaced. Ordered a spicer unit and it took me a couple of hours to do. It’s a pain, but pretty straightforward. Drove it to work today and didn’t notice any leaks. Made a huge mess of the undercarriage though which I now have to clean up :(