Would it be worth replacing the clutch at the same time as the rear main seal?

Roadhand01

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Was wondering, my main seal is leaking and I'm getting tired of stuffing a rag there to keep my driveway from getting oil all over it.
Question: if you were to replace it, would you also consider replacing the clutch and throw out bearing?
185k miles and original clutch as far as I know.
 
You don't need to separate the transmission and engine to replace the seal. Just pull the oil pan and rear crank bearing cap. It's a two piece rear main seal, unlike many other engines' rear main seals.

The clutch and throw out bearing would be good to replace if they truly are original (I doubt it with that mileage), but the two jobs aren't related at all.
 
You don't need to separate the transmission and engine to replace the seal. Just pull the oil pan and rear crank bearing cap. It's a two piece rear main seal, unlike many other engines' rear main seals.

The clutch and throw out bearing would be good to replace if they truly are original (I doubt it with that mileage), but the two jobs aren't related at all.
I appreciate your reply
 
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Please do this before going to the significant effort replacing the RMS requires.

I'm guessing your engine has been living on a synthetic engine oil. It's not uncommon for our engines to develop RMS leaks with many synthetic oils. It happened to my BMW too. If that's true, try this....

Change your engine oil out for a CONVENTIONAL High Mileage 10W-30. High Mileage conventionals are not always easy to find but it's worth the effort. NAPA sells a 10W-30 High Mileage that is a conventional. High Mileage engine oils contain additional seal restorative components that will often cure (not plug) a RMS leak.

My BMW developed a really bad RMS leak and the local German shops were quoting pretty close to $2k to repair it. A bunch of BMW owners in various BMW forums suggested switching to a high mileage conventional and damned if it didn't cure the leak in 5-6 days of daily driving. Good thing too, I was getting sick and tired of cleaning the big mess up off my garage floor.

I've never had a RMS leak in my TJ after 26 years of ownership. I've never run a synthetic engine oil in it either.
 
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Please do this before going to the significant effort replacing the RMS requires.

I'm guessing your engine has been living on a synthetic engine oil. It's not uncommon for our engines to develop RMS leaks with many synthetic oils. It happened to my BMW too. If that's true, try this....

Change your engine oil out for a CONVENTIONAL High Mileage 10W-30. High Mileage conventionals are not always easy to find but it's worth the effort. NAPA sells a 10W-30 High Mileage that is a conventional. High Mileage engine oils contain additional seal restorative components that will often cure (not plug) a RMS leak.

My BMW developed a really bad RMS leak and the local German shops were quoting pretty close to $2k to repair it. A bunch of BMW owners in various BMW forums suggested switching to a high mileage conventional and damned if it didn't cure the leak in 5-6 days of daily driving. Good thing too, I was getting sick and tired of cleaning the big mess up off my garage floor.

I've never had a RMS leak in my TJ after 26 years of ownership. I've never run a synthetic engine oil in it either.
Mine has had conventional oil for at least the last 130k miles of it's 180k life. My RMS leaks, and I'll be replacing it in the very near future.
 
Mine has had conventional oil for at least the last 130k miles of it's 180k life. My RMS leaks, and I'll be replacing it in the very near future.
No doubt, anything can and will eventually go bad no matter what its environment is. But Rear main seals are also known to go bad from some synthetic engine oils but many respond favorably to a change to a High Mileage conventional engine oil.
 
No doubt, anything can and will eventually go bad no matter what its environment is. But Rear main seals are also known to go bad from some synthetic engine oils but many respond favorably to a change to a High Mileage conventional engine oil.
It's also a very well known wear item on the 4.0, plain and simple.
 
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Exhaust work is what to consider doing at the same time as the RMS...the down pipe needs to come out...or your Tetris skills for getting the oil pan out will be tested.

Good thing to have a new exhaust gasket on hand...and most people...me included...screw up the install the first time...I put mine in and a little sliver of the seal came out...best to have two of them on hand. I've got to do mine again...

Another thing to have on hand is plasti gauge and assembly lube. My bearings didn't look happy. On my second run I'm Plasti gauging the bearings. Assembly lube for the reinstall...I used 85w140 the first pass.

-Mac
 
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Definitely give the high mileage oil a try. I've had success slowing rear main seal leaks on 4.0L's with Valvoline MaxLife 10w30.
 
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Ok that's your opinion, it's not mine.
I do appreciate your help with this matter. I haven't used synthetic oil in it and according to the PO, he didn't either. I'm the 2nd owner so I'm sure it never had any in it.
It's always dripped a little and I have stuffed a rag up next to it to keep any oil off my driveway. I'm considering replacing it as within the last 2 months I have replaced the starter, fuel injectors, and water pump (2nd time Molar pump).
Since I'm "on a roll" thought might as well fix the only remaining item that needs repair at this time. I drive it everyday and like it to be in as good of shape as possible for a 22 year old.
 
If it's only dripping a little I wouldn't worry about it. That being said, if you do decide to replace it I would do the valve cover gasket at the same time. It can be hard to tell which is the source of the leak and if you only do one and it still leaks you may think you need to redo the job when it could be the other. I'm not sure if you intend to tackle yourself but they both took me a while.
 
And don't do it when it's 108 outside, even if you're in a garage. My timing was not ideal that week a few years ago.