Brand spankin new member with my recently purchased 97 XJ 4.0

[supark]

Brand spankin new member with my recently purchased 96 XJ 4.0

I was shopping for a car that would offer: 4wd, bulletproof reliability, cheap and easy to repair, able to tow at least 3500 lbs, under $5k, and as a hopeful feature - would not be a total dog to look at. After asking around bimmerforums, I learned about the venerable XJ 4.0 Cherokee and that it would meet all of my needs while also looking pretty dapper at the same time.

Just bought a 1996 Cherokee XJ in Country trim (all power locks and doors), 4x4, factory tow package, with 119k miles and the most hideous wheels I've ever seen. Body is pretty straight with the except of a light wide dent on the rear passenger door and a love tap on the rear bumper. Paid $2800 private party, and I think I got a decent deal - not smokin hot, but better than average given the mileage and condition - it is very clean. I also just noticed that it has an immobilizer installed with a digital key under the dash - pretty sweet and something I was planning on getting anyways given SF's petty crime rate.

Planning on doing the following preventative maintenance and cosmetic mods to start out with - anything else you guys think I should do? Also what's the best place to get filters, parts, etc?

• automatic transmission fluid/filter change
• run some chevron techron injector cleaner through a tank of gas (doing it now)
• install B&M auxiliary trans cooler
• fuel filter change
• run a quart of automatic trans fluid in the engine for 10-20 miles and then change oil and filter
• get some rustoleum bed liner paint and do the front and rear bare metal fenders in black (after I pound out the love tap in the rear)
• Radiator flush with prestone kit

Some concerns:

• When I initially took it for a test drive, there was a very slight knock at idle and a little stumble. Nothing severe and honestly not as bad as some bmw I6s I've owned, but after I drove it about 55-60 miles back home I noticed that the knock had gotten louder and the idle stumble slightly worse. It sounds like the knocking is coming from one of the middle or rear cylinders - the best I could describe it is kinda like thicker dishes lightly rattling against each other. Is there an inherent knock sound to these 4.0 I6 HO engines? Or am I looking at something perhaps serious? It's weird though because I can hardly hear it when I first start the car.
• Steering has a fair bit of slop and seems to pull a little to the left with the steering wheel perfectly centered. I'm guessing tie rod ends and other suspension bits would benefit from a freshening - what's the best way to test for wear on these?
• Power steering fluid is low - not surprised that there's most likely a leak, I'm guessing it's at a hose clamp beneath the reservoir because when I did the underbody check I saw fluid only on the front of the engine and the valve cover gasket didn't seem too bad.

I'll wrap it up with some pics of course As you can see it is pretty damn clean. The wheels as already mentioned are XXXXing hideous, so need to get maybe some later model steelies stat.

 

[supark]

realized the title says 97 - it's actually a 96 as described in post. After doing some research here it sounds like the light idle stumble is very very common for the 4.0 HO I6s - the knock when the engine is fully warmed up is still bugging me though. Worst case scenario I'm guessing it might be a bad rod - but wouldn't that knock all the way through the rev range? I only hear the knock at idle and hardly at all when the engine is cold. Also read that it could possible be a loose flexplate bolt.

 

[xcm]

welcome to the board....
i'd start with a full tuneup, spark plugs, wires, cap/rotorl, fuel filter (you mentioned that). MAYBE O2 sensor, if your feeling frisky or it seems to burn more gas then it should (might be hard to gauge coming from a bmw)
the knock might be flexplate/torque convertor bolts, pull the trans inspection cover and check the bolts for looseness... mine were loose but unfortunately not the cause of my knock during cold startups.... i do also have knock at idle sometimes....
ive been told not to worry about the knock... even if its hard to do that

 

[xcm]

as far as the steering box leak/dead spot...
have someone turn the wheel lock to lock in park, while you watch the hoses for leaks that develope under pressure... specifically the pressure hose, but can be either one, both, or as simple as a loose hose clamp on the return... Hopefully its just a hose, and not a dead steering box. coming from a bmw, you might be surprised to find out a lot of xj people do their own tape measure alignments... http://go.jeep-xj.info/HowtoAlignment.htm
to check tie rod ends, jack up one wheel, and put two hands on the outside edge of the tire, at 3, and 9 o'clock, and shake the wheel, there shouldnt be play.. but a worn steering box could show itself here as well.
if you move your hands to 12, and 6 o'clock, and do the same test you can check for ball joints.

 

[D.I.T.A]

welcome. that light knock is most likely piston slap another very common thing for the 4.0l. there is a lot of of little things you can do to get more driveabilty and performance out of it good luck with it

 

[supark]

just got back from a shopping trip from kragen:

7 quarts of 10w30 mobil 1 synthetic motor oil and bosch oil filter
Fuel filter
transmission filter kit
4 quarts of dexcron/mercon atf fluid
high pressure steering line (tracked the leak to the top of the reservoir where the high pressure line begins - so I'm betting that's it
some extra power steering fluid in case I lose a bit

Is it strange that I'm looking forward to spending a lazy sunday under my car doing maintenance?

 

[theNAST1EST]

Is it strange that I'm looking forward to spending a lazy sunday under my car doing maintenance?

Get used to it...your XJ saga has begun, haha. Welcome, and enjoy.

:cheers:

 

[Kiefer316]

Um its saturday... But anyways Welcome... If you have plans to lift it it won't stop after you wheel it you will always want more... And Very clean 96 xj... And im guessing the knocking you are hearing is just the exhaust manifold is cracked... All of them crack on these dang things...

 

[Ecomike]

Welcome and congrates on the real nice XJ find.

I will take one item for now, the warmed up engine knock and miss. Could be any one of many things.

I would pull the spark plugs, and check their condition, and make a map of how each one looked on paper. Check the cap, rotor, and wires for age and wear. Look for an exhaust leak, crack at the manifold joints, loose manifold bolts. Check and repair as needed the vacuum lines. One of the vac lines leads to the MAP sensor on the firewall from the throttle body, that vacuum line is critical to engine performance. Replace anything that is obviously bad, but check here first for the best parts brand and sources for all the parts.

Take to a local parts store with a free OBD-II scanner service, and get the results.

Spark plug inspection may tell you a lot about how everything is running, rich lean, one bad cylinder perhaps, etc. Do that before you spend any money on parts.

 

[sbxj]

welcome, keep your checkbook open

 

[Ecomike]

huh?

Cracked E-manifolds are common on the 4.0 L. Then can make a ticking, sound when cracked.

 

[sbxj]

Cracked E-manifolds are common on the 4.0 L. Then can make a ticking, sound when cracked.

true, I had it happen to my '93 but it didn't sound anything like the noise being described

 

[Ecomike]

true, I had it happen to my '93 but it didn't sound anything like the noise being described

Depends on where the crack is, and it's size. Also if it is near, and in front of the O2 sensor it can confuse the computer, and cause misses, and other annoying symptoms.

Frankly, noises are hard to describe, especially 4.0 engine noises. Like trying to describe the shape and size of invisible electrical gremlins. :laugh3: So I don't put a lot of stock in peoples description of a jeep engine noise.

I had loud diesel engine noise, that I just wrote off as normal for years (just thought it was an old tired, engine), that I stumbled into the real source one day. It was a loose donut on the exhaust flange.

I still have scary rod knock sound and tick on my 87 that I have had for 4 years, and 40,000 miles. It passed tough emissions tests last year with flying colors, and it gets quieter as the years go by. My daughters was cracked at the final joint, Renix 89. 5-90 and I discussed that a flex joint after the manifold might solve the problem.

 

[supark]

Just finished up replacing the fuel filter, oil and oil filter, and steering high pressure line. So far I gotta say I'm still pretty stoked about how cheap the parts are for this car - a high pressure line on a bmw can cost upwards of $150-200. On the cherokee - $20 and I can get it at my local kragen/shucks.. amazing. Some very dirty gas flowed out of the fuel filter - glad I changed it out. It might be just my imagination but it seems to idle slightly smoother now.. probably just in my head. Power steering pump is still a little noisy even with the fluid filled completely, so I'm guessing the PO ran it too often with low fluid and it's been damaged a bit. Still fine for now but might tackle it in a few months depending on how long it lasts - it occasionally will be a bit higher effort to turn when I'm parallel parking.

As for the sound, I am more and more convinced that it's transmission related - ie loose bolts on the flex plate. After a short 10 minute drive I noticed the knock/clatter when I was parking my car. I noticed that when I'd shift between park and drive the noise would subside just as it shifted into drive and then after a bit start clattering again - which sounds like classic signs of the flex plate bolts.

Not planning on lifting it - I bought it as a towing/hauling/4wd winter car. I however would like to get a tire/wheel combination that looks a bit more aggressive. They look like stock 7-8" wide tires and have decent tread on them though so would be a shame to just throw them out. I like the look of those mickey thompson rims though - classic design.

I was talking to my neighbor about the steering play and he said that it's normal for 4x4s - so when you're out on trails and your wheels suddenly get jerked in a certain directly the steering wheel doesn't start going crazy on you. I'm inclined to believe that - kinda that "loose gun, tight gun" philosophy.

The more I look at the bare metal bumpers, the more I actually think they look decent on the car - gives it a classic look. I just need to pound out that dent in the rear bumper!

I'm debating getting a slightly nicer aftermarket head unit than the crap kenwood in there now - petty crime and car break-ins are rampant in SF, so wouldn't want to get anything super nice. Just a sub-$100 cd player with an Ipod plugin. Trying not to throw too much money into the car, but being that I use it as a daily drive some decent component speakers would also be awesome along with a compact 10" sub strapped down in the rear.

I have to admit I'm somewhat of a mod-addict (which it sounds like many of you are here on the forum) so I'm trying not to go crazy!

 

[joe_peters]

Bad neighbor, no cookie for the neighbor!

You should get under there, wheels on the ground, and have someone move the steering slowly from lock-to-lock and watch for looseness or play in the components.

Your XJ ain't no BMW, hell, for that matter my ex's Pinto wagon had rack and pinion steering, but it shouldn't be "loose". Check TRE, track bar mounts, UCA & LCA, check the ball joints and check the unit bearings. While you are under there check the axle and driveshaft ujoints too.

Until lifted and having the rear sway bar removed the XJ is a nice handling rig.

 

[winterbeater]

IMHO, the best thing about an XJ, compared to a Beemer, is that you can crawl under it without ramps or jacks. Like joe said, it's easy to find out if any steering components have excess play by laying underneath while someone cranks the steering wheel back and forth. And you can do the wheel alignment with a tape measure!

 

[supark]

IMHO, the best thing about an XJ, compared to a Beemer, is that you can crawl under it without ramps or jacks. Like joe said, it's easy to find out if any steering components have excess play by laying underneath while someone cranks the steering wheel back and forth. And you can do the wheel alignment with a tape measure!

No joke - I was just about to post this. In many ways it's so much easier to work on the XJ. I did all the work today without touching my jack - I could probably convince myself that a modest 2-3" lift would be in my best interest to make the truck that much easier to work on! And btw - "beemer" is the term for a bmw motorcycle and "bimmer" is a car.

 

[Kiefer316]

Ya know whats really cool when you can sit underneath where the rear driveshaft is, doing an SYE on a t case pretty much sitting straight up. I shoulda got a pic of that haha... I am at 4.5 in the front an 5.5 in the rear..

 

[Ecomike]

No joke - And btw - "beemer" is the term for a bmw motorcycle and "bimmer" is a car.

I always thought if it wasn't a jeep it was "bummer"!:laugh3:

 

[FlexdXJ]

Until lifted and having the rear sway bar removed the XJ is a nice handling rig.

They still aren't bad as long as the front sway bar is on there.