Reliability of Jeep 4L

[JMyerz]

Hey all,

I've had several jeeps but never in the 100k range of milage on the clock. I am curious as the long term reliability of this engine. I've noticed 97+ XJ come way down in price and have considerd getting one as a DD and light expedition vehicle.

My first choice was a Tacoma and I did infact purchase one, however my photography business is starting to grow and I need a vehicle with more / better seating.

Thanks

Justin

[goodtimes]

Mine only has ~58K on it....but that would be a trouble-free 58K. I have not heard many complaints about the 4.0L......

[Scott Brady]

I would caution against the purchase of a Grand Cherokee. Not because they are not great off-highway vehicles, or wonderful road cars, but due to reliability issues. I have owned two. The first made it about 90k miles before major issue started cropping up, and the second only made it to 50k before the transmission started going.

I would recommend the following (in order of least to most expensive):

2001-2002 Trooper
Nissan Xterra
Toyota 4Runner

What price range are you considering?

[Scott Brady]

And to more clearly answer your intitial question:

The 4.0L motors are very reliable. I have 140k on my Jeep Wrangler and it has never required any service.

[cshontz]

Justin,
The Jeep 4.0L I-6 is extremely reliable. If you Googled that engine, or went onto various Jeep forums, you'd be hard pressed to find one that died after any number of miles - providing it was properly serviced during its life. I read about them going over the 200k mark all the time.

I've owned five 4.0L I-6 Jeeps, and drove every one up to around 120-130k miles with no problems, and none of them have showed any sign of slowing down.

A typical characteristic of a high-miles 4.0L is just oil seapage, usually around the head gasket toward the back of the block, and usually around the rear main seal. You should be able to find one that is dry, or nearly dry, but oil seapage becomes more common as you go up in miles. I suppose that would be true for almost any engine. :)

[JMyerz]

Thanks for everyones input.

We currently have an Xterra and its great overall. My parents had a late 90s trooper and had nothing but problems with it, maybe it was bad luck but its made me a little worried about getting one of those.

A 4Runner is too expensive right now, I can find a 97-99 XJ for well under $8k with under 100k on the clock. Thats one of the reasons I'm thinking about getting one.

I know the grands have been troublesome, and I'll stay away from those. I guess my only other concern is the unibody. I know the made the later model cherokees stronger but I am unsure of the overall strength of it.

Justin

[Scott Brady]

An XJ is a great choice... Good plan IMO.

Great trail performance, good highway ride and reasonable reliability. I have always liked them.

[OverlandZJ]

Many 4.0L's are on the road with 200-300K miles on them....or more.

Best bud's 94 YJ (bought new) currently has ~255K, my 94 XJ has 154K, and neither of us would hesitate to drive cross country. My wife's 94 XJ was bought with 40K, currently has almost 90 and runs like a top.

Proper maintenance is key, personally i run Mobil1 oil and filters exclusively.

[cshontz]

I guess my only other concern is the unibody.

The unibody should easily last the lifetime of the vehicle. The Cherokee is a popular choice for heavy modification and extremely technical trails, and even those guys have very few problems with the structural integrity of the vehicle. You needn't be concerned. :)

The biggest disadvantage of the unibody, that I can think of, is if the vehicle is damaged in a roll-over or a hard collision, there is a strong possibility that it is beyond repair, and you no longer have the option of replacing the body.

I think you will probably be happy with a Cherokee. The XJ platform was in production from 1984 until 2001, so it is definately a time-tested vehicle design. Aftermarket support is vast, ride quality and fuel economy is reasonable, and reliability is top notch. I'm sure lemons are out there, but my experiences have all been good.

Take note, that folks over 6' seem to feel a bit cramped, particularly in the 97+ models. They seem to have increased the height of the front seats slightly on the later models. In addition, some have suggested that the seats don't slide back far enough. I'm 5'7", so I fit in mine like a glove, but I can see how people with bigger frames might not be comfortable. The back seat doesn't offer a remarkable amount of space for adult passengers either.

My biggest (and perhaps only) complaint about the Cherokee XJ is the lack of a folding split rear seat. The back seat does fold down to offer a good bit of usable space, but if you have a third passenger, and still need extra space, you're out of luck. :(

Good luck with your decision!

[sacto_patrol]

I have had two XJ's an 88 and a 99. I would suggest staying with a 97-99 XJ. You get the high pinion 30 with 297 u-joints up front (basically as strong as the dana 44 in the front of the new rubicons) and look for a tow package with the 8.25" chrysler in back. These model 8.25" had 29 spline axles and are very strong. Being one hour and 15 minutes from the trail head of the rubicon I have beat the hell out of both XJ's. The unibody holds up fine, just watch for cracking at the upper control arm support. The first thing I would suggest is to get sliders on as the rocker panels are very diffcult to replace. Also I would stay below 4.5" on the lift. Rubicon Express is the best IMHO in regards to XJ suspensions.

[UncleChris]

I retired mine('98) at 175k miles, the engine was not sucking any oil and was very strong. The whole machine was pretty sound. After I put the lift on at 75k, I had not had to sink any money into it. Other than oil changes and regular upkeep, never needed any service at all.

A friend of mine has one with 230k that he has not sunk any money into for ages. Although when he took it into the dealer to have the Motor/Tranny mounts changed it developed a leak.(hmmmmm)

The only reason that I got rid of mine was that I needed something that I could commute in and at times I regret not getting a second car and keeping the XJ. We also needed something a bit bigger.

Be aware that there is not much leg room in the rear of the XJ.

[ShottsCruisers]

Thanks for everyones input.

We currently have an Xterra and its great overall. My parents had a late 90s trooper and had nothing but problems with it, maybe it was bad luck but its made me a little worried about getting one of those.

A 4Runner is too expensive right now, I can find a 97-99 XJ for well under $8k with under 100k on the clock. Thats one of the reasons I'm thinking about getting one.

I know the grands have been troublesome, and I'll stay away from those. I guess my only other concern is the unibody. I know the made the later model cherokees stronger but I am unsure of the overall strength of it.

Justin

What about an 80-series Land Cruiser? They're out there, with triple factory electric lockers (saves $$$z cuz you don't have to add) and 35's fit with a $750 lift. They're 200K+ mile machines and can be had for 8-10K (only get 93-97). Don't let something like 140K miles scare ya. They're indestructable and incredible off-road. :)

[JMyerz]

I had thought about an 80 series as I love the LC, but the gas milage is horrible in comparison.

I also like the nilbe lighter weight design of the XJ.

Thanks for all the input, now its time to sell the current ride and find one...

-J

[OverlandZJ]

I had thought about an 80 series as I love the LC, but the gas milage is horrible in comparison.

I also like the nilbe lighter weight design of the XJ.

Thanks for all the input, now its time to sell the current ride and find one...

-J

Dont know where your located but these two sites always have several XJ's for sale.

www.naxja.org

www.jeepsunlimited.com

[XXXpedition]

here are my 2 cents in short:
my '94 xj: 203k very hard miles - everything original but water and power steering pump.
a friend has 4 '89 xj's:
1. 270k miles all original but water pump, injectors
2. 170k miles on rebuilt motor all original
3. 150k miles on rebuilt motor all original
4. 180k miles (just bought it - has oil leak)

i think it's a great engine, easy to work on, very cheap and parts readily available in most auto part stores.

definately a good choice! very reliable for small price and aftermarket is big and affortable.

[br1anstorm]

I agree with previous posts. Look after the 4.0 litre engine (like John B, I recommend Mobil 1) and it will last well. Mine's done 120k and hasn't missed a beat.

Now the body... that's another matter. Unibody structure is OK, but why doesn't the factory rustproof them properly? The forums are full of pics of XJs with rusted-through floorpans, and there seems to be a lucrative business in replacement pre-formed floor panels. Salty winter roads are deadly (and there's that pesky aircon-drain leak which soaks the soundproofing under the carpet and rots the footwell). If you have an XJ with body in good condition, then rustproof it well (Waxoyl, Dinitrol, or similar). More important to protect the outsdie than to Herculine the inside!

br1anstorm

[jerdog53]

I have or have had 4 of them and none of them ever gave me any trouble the highest mileage unit was in a 77 CJ5 and went over 180K on it before the compression was to low to work with. After a ring and valve job it was like new again. I have a 2001 WJ with 88K on it now and have done nothing to it but fuel oil water. My 05 LJ Ruby has 25K on it with out any problems. I had a 83 CJ5 with the 258 I6 in it and the vacuum hoses dry rotted out after ten years and caused problems but once I replaced all that it worked much much better.

[Incadude]

One stop shopping:

Jeepforum.com (www.jeepforum.com) Under Vehicles for Sale

There you'll find numerous XJ's bone -stock to fully loaded. I'm always amazed at how low the price is on these. It really makes a mod’d-up XJ real tempting. O, and don't worry too much about the I6, super strong, super reliable...

Best of luck.

[XXXpedition]

i can only add:
mine had 250k and was still running strong. only parts i changed:
water pump, alternator, pumer steering pump...
i know of 3 other cherokees with 200k-350k on the original engine...

do i need to say more :-)))
i'd only stick with a 94 or younger because of the high output engine...
sven

[calamaridog]

In this day and age there is no excuse for any engine not to offer reliability into the 150k range. Pushing beyond 200k is nice however:REOutArchery02:

The 4.0 I6 was a good motor and it is a real shame that Dailmer did not update the motor to meet current emmissions laws:(

[RunninRubicon]

Did you know Benny down at our friends in Burmingham, Alabama built that beautiful aluminum super-free flowing cylinder head in an attempt to sway MOPAR to contiue to use the I-6. It would have given the 4.0L I-6, 30moreHP and 35 ft lbs of torgue more then the 2006 of 190hp and 235. This head added to a 4.6L stroker kit, a mild cam for emissions sake will net 300hp and about 365fl lbs of torgue! MOPAR saw a chance to increase the profit potential by using a motor less expensive to build an one that can be used in a multitude of autos. The I-6 could only live in a Jeep. It's all about $$$.
I read in 4wd and Sport Utility mag that a CRD is coming to the Jeep line-up for the USA. Ford is going to use a Land Rover diesel in some of its vehicles.
Toyota and GM both use input from Isusu for diesels for their line of vehicles. If I read between the lines I can see Bio Diesel as our future. Invest now. E-85 here we come!

[toledotimber]

Although I have a cowl snorkel on mine, I sank it in 4 1/2' of water last October, and all I had to replace was the upstream O2 sensor. These engines are very durable (cast irons heads AND blocks!). Stay away from 2000s and '01s due to potentially getting the notorious 0331 model head casting. It is known to crack between (IIRC) the number 3 and number 4 cylinders. Also, up to '99 they came with stronger high-pinion Dana 30s.

[RunninRubicon]

Although I have a cowl snorkel on mine, I sank it in 4 1/2' of water last October, and all I had to replace was the upstream O2 sensor. These engines are very durable (cast irons heads AND blocks!). Stay away from 2000s and '01s due to potentially getting the notorious 0331 model head casting. It is known to crack between (IIRC) the number 3 and number 4 cylinders. Also, up to '99 they came with stronger high-pinion Dana 30s.

A friend in my Jeep group rolled a 05' LJ Rubi last year. It rolled three times and totaled the body. After putting it back on it's feet and out of the trees, we pulled the radiator support back from the fan, pulled the plugs and cranked it over to blow all the oil out of the cylinders. Replaced the plugs, added three quarts of oil and a bit of power-steering fluid and cranked it up! He drove it 17miles back to the highway then drove 50mph another 20miles back to the guys house! Never got hot nor lost oil pressure. Had to add a quart to the auto tranny but it shifted perfectly!. The motor has seven main bearings!. V8's have but 5. TUFF engines! Tuff as a Timex-takes licken and keeps on ticken!

[BigAl]

I just killed a 230K 4.0 last year by inhaling some water. If I hadn't, I'm sure it would still be running strong, it didn't smoke or use oil. It had a little noise from the valve train.

[XXXpedition]

with the 250k i had on mine i never put in any oil inbetween oil changes.
perfect...