Considering an older XJ. (Maybe ZJ.) Any advice?

[notnsuv]

Had this '99 since forever, probably 2010. Paid $3500 and worked it over. 124k to 154kmi.
'99 is the best, partially due to the head that doesn't have the problem of the 2000+.
4.0/AW4 4.56/33" BFG KM2 (would prefer 4.88), ARB lockers front and rear, Yukon axles, sleeved tubes, Warn hubs, 4 wheel disc brakes, Warn 9000i.
Rusty's armor/fenders, JCR disco, 4"-ish lift with overload spring on the rear (can't remember the vendor)
This has been dead reliable through thick and thin. When I slog the mud or such, it's the XJ

I should have reinforced the 'frame' from the git-go but no ill effects yet. It's actually my DD during the winter.

As far as manual vs. auto: the 5spd manual is a bulletproof trans as is the AW4. Wheeling? I loved having the 6spd manual/51.3 at Moab in May. Watching everyone in front of me hitting the brakes off a ledge was cool; I just found the gear, stayed there, and idled off the worst of them (albeit, not the worst of the worst, I wasn't there for that).

All I've had to do other than routine maintenance is replace a TPS twice after going through a car wash with hood louvres. I've since sealed the TPS and avoid automatic car washes. Have never had to add oil.

 

[lBasket]

The years of XJ guys and their love of sawzalls catching up with the market....

 

[TJMexico]

I owned 3 XJs with various modifications over the course of 13 years and they are great, but finding one that hasn't been beat up is a real challenge now, and you will pay significantly for it. Almost to the point where it doesn't make sense to buy one for wheeling, because you will pay that much for a decent one.

1987-1990 were the "renix" years, with renault/Bendix fuel injection. 1991+ were the 4.0L "High output" years which made more power and were simpler. I owned a 1990 renix 4.0L and as long as you were good with a multimeter it wasn't too hard to fix, but the renix specific parts are becoming harder to find. I would really recommend 1991-1999 as the "sweet spot".

1996-2001 had OBD2, 1997+ were the refreshed smoother body style. 2000-2001 had the crack-prone 0331 cylinder heads.

Rust is obviously something to watch out for, and ultimately what kills XJs. They like to rust at the bottom of the doors, the floors, and the rocker panels. They also like to rust above the windshield where the windshield seal is, and that is what kills a lot of them, because it spreads underneath the seal, and Jeeps that look otherwise clean can have a ticking time bomb underneath the windshield that requires significant body work to fix.

If it were me, I think a 4.0L ZJ is a better value. Yes, the 42RE automatic is much weaker than the AW4, but the ZJ is larger inside, has coils all around like the TJ, and parts are cheaper. For the price difference between a clean XJ and a clean ZJ you could buy quite a few transmissions.

Thanks. You give me much to think about and I think I'll throw some ZJs into my mix. There are a few out there.

Appreciate the input.

 

[notnsuv]

The diffs in this picture are in my XJ. I bought them from Eric way back when he was redoing his XJ. Sleeved, armored, Yukon, ARB, disc brakes, Warn hubs, the complete set, front and rear for $2800. I never jumped so high or fast in my life. They've been flawless for years.
The book is out of publication I think, and mine went to a guy who moved out of state after I'd loaned it to him.
NAXJA is your friend. I'm probably NOTNSUV over there as well.

 

[notnsuv]

You want a 4.0l powered xj,none of them had carburetors. 97 up as they are the better obd2 style.

The 4 cyl and 2.8l chevy motors should be avoided.

That white '99 looks pretty clean. Great start on your 'build'. This opinion is without a lot of details.

 

[jeepguy03]

The years of XJ guys and their love of sawzalls catching up with the market....

Yup, but they were also like the #2 or #3 vehicle traded in to cash for clunkers, and everyone who owned one in my area thrashed it through the salty snowy winters, which is how all 3 of mine died. Fluid film and frequent car washing in the winter only kept the rust away for so long, which is why my TJ is now a summer only vehicle.

 

[jeepguy03]

Thanks. You give me much to think about and I think I'll throw some ZJs into my mix. There are a few out there.

Appreciate the input.

I just think you will have an easier time finding a cleaner ZJ for a fair price. The XJs are out there, but you will have to search for a long time and be very particular about what you are buying, which is difficult when they sell quick even at the high prices.

 

[TJMexico]

Yup, but they were also like the #2 or #3 vehicle traded in to cash for clunkers, and everyone who owned one in my area thrashed it through the salty snowy winters, which is how all 3 of mine died. Fluid film and frequent car washing in the winter only kept the rust away for so long, which is why my TJ is now a summer only vehicle.

That is an issue here, but because they drive them out on the beach and in the dunes. Sea water.

 

[TJMexico]

I just think you will have an easier time finding a cleaner ZJ for a fair price. The XJs are out there, but you will have to search for a long time and be very particular about what you are buying, which is difficult when they sell quick even at the high prices.

All your talk about the ZJs and their sweet spot, I jump back on FB Marketplace (preferred spot for shopping around here) and found this one just posted this evening. Looks like a lot of mods, though, and from what I read, it has not been registered since 2014, which means back taxes due on it. Asking price is about $4,350usd, but I have no idea what those back taxes might be. Plus, all those mods kinda scare me.

https://www.facebook.com/marketplace/item/1504506187367195

These are the mods, listed in English. Seems like maybe too much...

FOR SALE: 1999 Grand Cherokee
4.0L Engine (Boosted to 4.9L)
Crower camshaft, springs, and lifters
Ported cylinder head
Ported intake manifold
4.7L Open-faced cylinder head (coin bore)
Chevrolet 6.0L pistons
12-bearing crankshaft (Rambler)
Header performance exhaust
Reprogrammed ECU
Semi-rigid engine and transmission mounts
Adjustable external fuel pressure regulator
High-pressure oil pump
Toyota transmission
Valve box pressurized
3" exhaust pipe
High-flow Rush exhaust
Adjustable front suspension
Rubicon Express front springs
Rancho shocks
Registration valid until 2014

 

[ColoJeep]

All your talk about the ZJs and their sweet spot, I jump back on FB Marketplace (preferred spot for shopping around here) and found this one just posted this evening. Looks like a lot of mods, though, and from what I read, it has not been registered since 2014, which means back taxes due on it. Asking price is about $4,350usd, but I have no idea what those back taxes might be. Plus, all those mods kinda scare me.

https://www.facebook.com/marketplace/item/1504506187367195

These are the mods, listed in English. Seems like maybe too much...

FOR SALE: 1999 Grand Cherokee
4.0L Engine (Boosted to 4.9L)
Crower camshaft, springs, and lifters
Ported cylinder head
Ported intake manifold
4.7L Open-faced cylinder head (coin bore)
Chevrolet 6.0L pistons
12-bearing crankshaft (Rambler)
Header performance exhaust
Reprogrammed ECU
Semi-rigid engine and transmission mounts
Adjustable external fuel pressure regulator
High-pressure oil pump
Toyota transmission
Valve box pressurized
3" exhaust pipe
High-flow Rush exhaust
Adjustable front suspension
Rubicon Express front springs
Rancho shocks
Registration valid until 2014

Some of the " mods " don't exist in real life . In my opinion I would pass . The largest bore on a hot rod 4.0 is 3.935" , this ZJ allegedly has a bore at least .065 "
larger than that . Not something you want to deal with . I hope the search goes better !

 

[jeepguy03]

Some of the " mods " don't exist in real life . In my opinion I would pass . The largest bore on a hot rod 4.0 is 3.935" , this ZJ allegedly has a bore at least .065 "
larger than that . Not something you want to deal with . I hope the search goes better !

Personally, I wouldn't buy a modded vehicle. I've only ever purchased stock vehicles, or vehicles that are OEM+. 99% of the time the mods are not done well and they are just selling their headache on to someone else while also justifying their higher price saying the mods add to the value, which they do not. Start with something stock or close to stock so you can mod it how you want.

 

[TJMexico]

Some of the " mods " don't exist in real life . In my opinion I would pass . The largest bore on a hot rod 4.0 is 3.935" , this ZJ allegedly has a bore at least .065 "
larger than that . Not something you want to deal with . I hope the search goes better !

Pretty much where my thoughts were going (without the technical specs). The list seems way over the top. Not even gonna go there.

 

[srimes]

Personally, I wouldn't buy a modded vehicle. I've only ever purchased stock vehicles, or vehicles that are OEM+. 99% of the time the mods are not done well and they are just selling their headache on to someone else while also justifying their higher price saying the mods add to the value, which they do not. Start with something stock or close to stock so you can mod it how you want.

That's a very real risk. But if the mods are done well it's typically MUCH cheaper to buy one modified they way you want than to build yourself.

 

[TJMexico]

I owned 3 XJs with various modifications over the course of 13 years and they are great, but finding one that hasn't been beat up is a real challenge now, and you will pay significantly for it. Almost to the point where it doesn't make sense to buy one for wheeling, because you will pay that much for a decent one.

1987-1990 were the "renix" years, with renault/Bendix fuel injection. 1991+ were the 4.0L "High output" years which made more power and were simpler. I owned a 1990 renix 4.0L and as long as you were good with a multimeter it wasn't too hard to fix, but the renix specific parts are becoming harder to find. I would really recommend 1991-1999 as the "sweet spot".

1996-2001 had OBD2, 1997+ were the refreshed smoother body style. 2000-2001 had the crack-prone 0331 cylinder heads.

Rust is obviously something to watch out for, and ultimately what kills XJs. They like to rust at the bottom of the doors, the floors, and the rocker panels. They also like to rust above the windshield where the windshield seal is, and that is what kills a lot of them, because it spreads underneath the seal, and Jeeps that look otherwise clean can have a ticking time bomb underneath the windshield that requires significant body work to fix.

If it were me, I think a 4.0L ZJ is a better value. Yes, the 42RE automatic is much weaker than the AW4, but the ZJ is larger inside, has coils all around like the TJ, and parts are cheaper. For the price difference between a clean XJ and a clean ZJ you could buy quite a few transmissions.

What is the V8 like? Dependable? Pretty much all of the ZJs I am seeing here have the 8 cyl engine.

I am about to go look at this one. Price is right if it's in good shape, about $3,500usd. Actually, this one is a WJ...

https://www.facebook.com/marketplac...ferralSurface=messenger_banner&referralCode=2

Automatic
-A/c working well
-4x4
-new tires
-(positive differential)
-Leather interior, very good condition

 

[ColoJeep]

What is the V8 like? Dependable? Pretty much all of the ZJs I am seeing here have the 8 cyl engine.

I am about to go look at this one. Price is right if it's in good shape, about $3,500usd. Actually, this one is a WJ...

https://www.facebook.com/marketplac...ferralSurface=messenger_banner&referralCode=2

Automatic
-A/c working well
-4x4
-new tires
-(positive differential)
-Leather interior, very good condition

Mercedes influenced engine , plus wiring issues were common , would make a WJ a BIG no for me personally . My old supervisior's daughter had a new 05 WJ
it had so many wiring issues , she sold it at a loss because she couldn't afford to pay for it and constantly rent a car to drive . A world class $ 35,000 pile of crap.

 

[jeepguy03]

That's a very real risk. But if the mods are done well it's typically MUCH cheaper to buy one modified they way you want than to build yourself.

Sadly most who mod cut corners and do not do them correctly. I mean just look at some of the Jeeps people have posted pics of here they are looking at buying that the members here swayed them away from. You have to really know what you are looking at, or you will spend a ton of money un-F'ing someone's nightmare.

 

[jeepguy03]

Mercedes influenced engine , plus wiring issues were common , would make a WJ a BIG no for me personally . My old supervisior's daughter had a new 05 WJ
it had so many wiring issues , she sold it at a loss because she couldn't afford to pay for it and constantly rent a car to drive . A world class $ 35,000 pile of crap.

The OP asked about ZJs but posted a WJ.

93-98 Grand Cherokee was the ZJ, they offered the 4.0L i-6, the 5.2L V8, and the 5.9L V8 (1998 only). These engines are pretty reliable.

99-04 Grand Cherokee was the WJ, they offered the 4.0L i-6, the 4.7L V8 and the 4.7L HO V8 (2002+ on some trims). The 4.7L V8s were a bit more finicky about maintenance. I've seen many with 200k+ miles on them, but if they are overheated, it's game over as they usually blow head gaskets or drop valve seats shortly after. If you can find one with maintenance records, it will likely be fine, but don't buy a cheap one with zero maintenance history.

 

[speeding_infraction]

but if they are overheated, it's game over as they usually blow head gaskets or drop valve seats shortly after.

On the other hand, I overheated my 89 comanche 4.0 once since the shop that flushed the coolant didn't do it right (I know, I know...). It was in the red for at least 10 minutes. Filled it up with coolant and it was good to go, never had any issues other than that.

 

[Rickyd]

On the other hand, I overheated my 89 comanche 4.0 once since the shop that flushed the coolant didn't do it right (I know, I know...). It was in the red for at least 10 minutes. Filled it up with coolant and it was good to go, never had any issues other than that.

The 4.7l v8 is a whole different ballgame than the 4.0l.

 

[KennethS]

On the other hand, I overheated my 89 comanche 4.0 once since the shop that flushed the coolant didn't do it right (I know, I know...). It was in the red for at least 10 minutes. Filled it up with coolant and it was good to go, never had any issues other than that.

My ‘98 4.0 overheated to the point the engine stalled when the radiator top tank blew while the wife was on the interstate. Replaced the radiator and it’s been running fine for over 10 years.