So my 4.0 has 184k miles on it. I always change oil every 3500 miles or so. Ive never made the switch to high mileage, should i? Would it make a difference? It runs ok now. As good as a jeep will run for havin the **** wheeled out of it lol. It has a slight knock, been there since I got it years ago. And I also have a rms leak. I usually have to add a quart between oil changes. Anyways, last weekend I added a quart of oil and a quart of Rislone(?) oil treatment. Just saw it and bought it at Carqwest randomly. It quieted the engine down a little actually but now its makin around as much noise as before basically. It does seem to run smoother on acceleration though.

Anyways, I have a can of seafoam, I'm thinkin about usin half in my crankcase on Friday then changin my oil on Sunday. Yay or nay on Seafoam?

 

I have not used the high mileage oils so no advice there but I have used seafoam in my oil and was shocked at how thin the oil came out after a 20 mins drive before the oil change. I would strongly suggest you only drive it long enough to get the engine up to normal temp before doing your oil change. There is a risk the seafoam will clean old crud that's keeping seals sealed.

 

i run the castor oil high mileage and have never had a oil failure related issue ever 89 xj 4.0 189,000

 

How bout Changing the RMS. $25 plus 4-6 hours problem solved.

 

I've always had good results running Valvoline Durablend in all my high-mileage engines. My XJ is at 190K and I got it with around 160K. It leaks in all the normal places but not excessively. I have the stuff to do the filter adapter elimination with my next oil change and maybe the RMS this summer if it's still leaking after the filter adapter removal. My Subaru, my 4Runner and my Ranger all had over 100K on them and they never leaked a drop or had any kind of issues at all... with the engine. I've never tried "high mileage" oil, everyone I know says it doesn't make a noticeable difference. I also tend to think there are plenty of good oils out there, and plenty of "good" gimmicks too. I definitely agree that changing things suddenly on a high-mileage engine can work things loose and cause new leaks/problems though. Same goes for Jeep transmissions and flushing VS. just changing fluid!

...kinda like when I change what kind of food I feed my dog, his O-rings get all kinds of funky...

 

considering you have never used seafoam in your motor before I would not do it don't even think about all it will do will loosen old gunk thats already set in the motor and get sucked up in your oil pump and destroy it I've seen to many people destroy motors because this happened honestly haven't ever used the high mileage oil either it's always been the cheap autozone brand stuff just change it a little more frequently and i've got a little over 200,xxx miles

 

x2 old seals

 

my 2cts. on the oil vavoline maxlife $16 for 5qt. container @ walmart