First off, what oil are you using and what filter?

Secondly, use Restore instead of Rislone.

 

I have the stupid 0331 head but my question is how long it takes before it cracks?? im at 74k miles right now...

 

You have 74K on an '00 or '01. Wow. That is so low. Depends on who you talk too. Met a guy who worked at a Jeep Dealership as a mechanic. Said it was usually about 50 to 75K. A mechanic friend of mine fixed one at 126K. How long it needed fixing is anybodies guess. 155K on my '00. Pretty sure the head is OK. No milky oil, loss of anti-freeze, or low oil pressure at a very hot idle. Original Head? No idea. Is a 0331 though. Saw the casting when I did a valve cover gasket. Sometimes too I wonder if this is blown a bit out of proportion. Don't cook the motor, keep an eye on the fluids, and drive it.

 

I have a flat tappet engine so i use conventional and ZDDP.

 

So the 0331 head if not driven outside of specs and temp generally will work for quite a while, it's if you abuse your motor don't do proper maintenance when it really becomes an issue because of the flaws of it. That's not to say that you have to baby it by any means but they aren't hard to replace and you can pick up a new one from the JY or find any number of remanufactured or new heads online.

I have an '01 with 210k and the original (0331) head and motor, I've had no issues but I can tell it's time to take it off and start going through my motor due to it loosing it's pep, occasional misfires, low oil pressure, some ticking and a cracked header. And the last shop that I had service the AC didn't do that right so it hasn't had AC for about 3 years.

 

What's that have to do with a differential? lol

 

Thought he said engine as well. I do have dino in the diffs as well, but its old school trac- loc. I never got into the synthetic craze.

 

Frankly, that isn't true. The 0331 is really a craps shoot. You may mistreat it and never have a problem, or you may baby it and have a crack. That's why they're so infamous. It isn't because everyone has trouble; it's because anyone can.

 

excellent correction.

A friend have 250k on his original 0331 head and he abuse it pretty regularly.

I had a 01 with the 0331 head and in its service history, it had the head replaced three times. (105k miles, 137k miles, and at 155k miles)

 

Synthetic diff lube makes a world of difference if you live somewhere with winter!

 

I redid mine in my '00 with synthetic. Figured the fluid had 150K on it, plus all the top offs over the years, and needed to go. Went with Valvoline VV975. Used some gear oil RTV I bought at Napa instead of gaskets for the diff covers. Don't tow, don't wheel anymore, just a DD.

 

I'm using Valvoline High Mileage 10w-30 and a wix filter.

 

yeah i found this one with 73k on it, it was used by a state park somewhere in Virginia, they bought it new with only 23 miles on it! believe it or not, i looked at one that had 46k miles on it..... but the guy wanted 13 grand for it haha

 

Ah, well in that case im good. I live in the tropics and don't have a winter.

 

46K at 13K. Wow for the mileage. Ouch for the price. I bought my '00 kinda cheap. 147K. Needed some work. Knew about the head going in. Decided to chance it. I am always on the look out for a TUPY head locally, are tough to find, but not stressing the whole head thing. Figure if I do, get it checked and reworked, and if and when the time comes it's handled. Figure if not then do what everybody else does. Buy a Clearwater. Whatever is going to happen is going to happen. Worry about it then.