Xj Longevity

[RaptorXJ]

I've got a 1992 with 195k miles and it still runs very strong.

17-19mpgs usually, 40psi oil pressure, no rust, great heater, fits me, my wife and 3 kids whenever we're not in her ford.

Thats a minor issue I have is MPG. Granted it only gets 5K a year and does alot of short distance runs but when I first got my jeep near 5 years ago I got 16-18 MPG. Now I only get last 2-3 years 12-14. I tryed everything. Once a year (5K miles) I put new plugs, wires, cap, fuel filter. I just put another new coil on hopping to help MPG went from a stock to Acell. I have cat back exhaust, adjustable fuel presure regulator and put PSI to 49 with the 4spray tip ford injectors, a CAI and put the IAT sensor in the filter to keep the heat temp reading down, I have ran fuel injector cleaner and still 12-14 MPG. I do have 235-75-15 tires but I wouldnt think that would do it. I even have synthetic gear oil in the rear.

 

[ParadiseXJ]

i guess thats the sad part about it, if your in an area that gets freezing / wet/ snow weather that will take its toll.

luckily here in Australia we don't see that and can expect to get better service from a vehicle

Freezing wet snow is not what does it...it's the salt on the roads used back east/north. Out here in CA it isn't a problem. We have snow and ice in our area. Twenty miles away there's 2-3 ft. right now. We use decomposed granite (sandy gravel) on the roads...not salt.

Any way...I have an XJ with 235K on it...original engine, tranny, t-case and only superficial rust, no structural damage. I also have an 88 MJ with 185K that I've just about completely restored ($$$$) that I got with literally zero rust.

 

[Matthew Currie]

Yes, it's the salt and slush that get them. In between snowstorms our cars are white with crusty salt residue, even in a mild winter. My 99 was rust free when I got it a few years ago at 144K miles, and stayed nice for a while, but then it just blossomed. The floors are shot, the rocker panels went from a little blistering to gone in about two years, and it's getting the dreaded roof rot, which is part of what sidelined the 95 - the puddles on the seats when it rained were bad enough, but it also blew in cold air all over the place, and the heater couldn't keep up with it. The paint is also going on the roof and hood, with a million little rust zits. I just noticed a rot spot starting on the rear hatch too. If it weren't for the rust these things would go forever. I am guessing from the wear I've seen in my last two XJ's and in my stepson's that the engines would be good for well over 300 thousand miles if you kept a little oil in them, and probably the same for the rest of the drive train (except of course for the u-joints).

 

[clunk]

I'm on my 3rd XJ; I've owned a 1990, a 1998 and am now driving a 2000 model.

In between the XJ's I listed I owned a few other SUV's and 4x4 pickup trucks. Nothing really beats the Jeep. The only compromise that I feel I make with my XJ is a lack of cargo space sometimes when compared to a bit bigger SUV or truck, but the Jeep makes up for it with a solid drivetrain and decent fuel mileage (bone stock I get between 24-25 US mpg on the highway from my 2000 with 5spd whereas my 4runner with a smaller engine was lucky to get 15 on the highway!).

Have you checked the o2 sensor yet? These seem to be a culprit when there's a big loss in MPG.

 

[birchlakeXJ]

If it weren't for the rust these things would go forever.

So VERY true. Rust is the enemy........good luck to guys like me in MN; dead center of the "salt belt".

 

[kastein]

I would trust the motor in your '94 to go more miles than the motor in a '00 or '01. Why? The 0331 head is known for cracking more frequently than the others.

Keep it maintained and it will last effectively forever. And the best part? Parts costs...
- new-to-you 4.0, when it finally dies? I've never paid over $160. You can bolt in any XJ motor from 91 through 99 and everything will line up perfectly.
- new-to-you AW4? I've never paid over $75. You can bolt in any AW4 from 91 through 95 or 96 with no mods, 97s with slight wiring harness splicing, and 98-01s with a few parts off your old AW4 swapped on.
- new-to-you transfer case? Never paid over $100 and you can use anything from a 91 through a 95.
- new-to-you front axle? Never paid over $100, and anything from a 91 or 92 or so through a 99 will bolt right in.
- new-to-you rear axle? Never paid over $100 (seeing a pattern here? ), and any d44 or c8.25 from 87 through 01 will bolt right in and either be as good as, or an upgrade to your axle.
- new-to-you gas tank? Never paid over 120 for a new one... and 87 or so through 96 will bolt in.
- new-to-you radiator? 91 through 01 bolt right in, never paid over 160.

As long as the unibody doesn't rot in half under you, they are dirt cheap to maintain.

 

[lucky14]

brought my 98 back to life from a couple cracked piston skirts and a broken flexplate. Body is cherry and runs like a top, 188,937 - I was told by the previous owner it was a junker.

^^^ all I had to do was build the engine, drive it to my shop in at 8 AM, drive it out with a stroker at 5 PM with a new engine and throw a winch on it. To bring a mall and beach crawler back from the dead and hit the trail that same week for it's baptism of rock.

 

[forged]

I have 212,110 miles on the 1995, and it runs very smooth. These sequential port fuelinjected 4.0 monsters run for a long time. My friend has over 400,000 on his 1992 XJ, so I just think these engines are the best. Just changed all the bearings and Oil pump for fun, and the bearings only had minor wear. God Bless all Jeeps in California !!!

 

[Miller88]

Mine is starting to rust ... I really want to get another rust free one before they all disappear.

Who has the most mileage on an original AW4?

 

[kastein]

My 2wd AW4 has 240 or so on it when I pulled it. I think I was the first person to ever change the fluid in it, around 200k when my friend first bought it. I was not nice to it, I owned it from 207k to 240k problem-free, now Dundy owns it.

I killed two that were under 150k miles but one was slipping when I got it and I abused both severely, so it was pretty much expected.

 

[RaptorXJ]

Have you checked the o2 sensor yet? These seem to be a culprit when there's a big loss in MPG.

I did think of that when MPG started dropping about 2 years ago. And that is a good idea. I did replace my O2 sensor but doesnt mean its working correctly. The first one I got I installed and that was and is the only time the Check (service) Engine Light came on my jeep. I had to take it back to advance auto and they gave me another one. The 2nd one didnt throw the light BUT that sensor may be bad also.

I may look into getting another O2 sensor on that thought, thanks for the idea!