sycoglitch

Iirc the 97+ was all HO. Only things that changed was the exhaust manifold and they eventually went distributerless in later year modeled after 97. Someone correct me if I'm wrong

sycoglitch

And what makes you feel it's rod knock. What kind of oil you use in it.

Lowrange2

So, did you go jump the starter?

cruiser54

Correct. HO came out in 1991. They quit usting the Highly Overrated tailgate badges somewhere along the line before 1997 .

sycoglitch

Were all 4.0 s high output or just the later ones?

njxjallday

alright so the cluster in my 99 cherkee spport worked yesterday...and now its not working. all the lights still light up behind it like blinkers high beams check engine and airbags stuff like that but the gagues dont do anything. it seems to me like maybe a ground wore fell off or something ? any ideas would be much apreciated i hvae no clue how much gas i have i also haev a gian pile of wires and relays fro the previous owner. i hvaent dug into them for gear of screwing somethin els up so the more specific you could be the better thanks

cruiser54

91 and later were all HO. Not one bit more torque than a Renix and a total increase of 8 HP over a Renix, at about 1500 RPM higher.

The difference is largely due to an increase in throttle body size and freer flowing exhaust.

Great marketing plan by the Chryco guys.

bulrid8

Smack top of dash and see if they come back. Check grounds and pull cluster and clean connections.

dwilly

i dunno its my first jeep and ive only owned it for 7 months.

dwilly

i used penzoil high mileage 10w-30 and its started making a loud knocking noise as i was going down the road and gets louder as i acellerate. i stopped at a mechanic i know he said its most likely the rod knocking.

ThatPurpleXJ

Probably rod knock, don't worry not to big of a deal. Try to get an engine from 91-99, pre 91 is the renix era and 00, 01 are prone to the head cracking. Get the long block and swap over all of your accessories; sensor's, intake and exhaust manifold, alternator, etc.

If I was you I'd replace somethings before putting the new engine in too. Oil pan gasket, rear main seal, oil filter adapter gasket, valve cover gasket, water pump, thermostat, normal things that go on the 4.0 but doing the work on an engine stand will make it heaps easier.

I'd say continue driving your jeep if you know you're going to get a new engine. I've had rod knock for nearly 600 miles and I just go through a quart of oil a week. Go easy on it and see how long it will last.

dwilly

thanks alot!! this gives me a project to do at least. i cant say that im gonna have nothing to do! thanx everyone for all the info. if it wasnt for this site i dont know what i would do. except spend way to much money for a mechanic. thanx again

NewKindOfClown

'00/01 are also distributorless. Add freeze plugs to the list of things to replace.

DigitalBman

Can I comfortably put a 3 inch lift on a 95 grand cherokee zj, without replacing anything?

I would be doing the budget boost spacers that go under the springs.

Thanks!

ericsvb

I just pulled and rebuilt the motor on my 2000 cherokee earlier this year.. It is Not a difficult project-- will take some time and carefull attention to detail, but its not impossible. A local shop here in Grand Rapids, MI rebuilt the entire engine for less than $1500. You could probably do it yourself for less..
Anyway, PM me if you want more info or to talk about the project.. I have pictures too.
Update: I drove it for a year or two with slight knocking- only after It got much worse did it go out on me on the highway, towing a trailer.
Try dumping Seafoam in the engine oil to loosten/clean lifters if they are causing the noise, this might buy you some time.