iateeple

Hello all,
Question concerns my wife's 2003 Grand Cherokee. 4.0,auto,4wd. We have owned this car since about 60,000 miles,it now has 128,000 and some change. So two days ago I proceeded to change the oil in preperation for the trip with the fam to disney world in Orlando ( We live in Greenville,SC). As I always do I changed the oil with 6 quarts of 10w-30, I have maintained the vehicle very carefully and have never had the first problem. Driving around before the oil change it was fine. Changed it,and as soon as I started it got a VERY pronounced tapping from,I think,the top end. Oil pressure read good per the crappy factory gauge. This sound continued for at least three minutes,I turned off and restarted no effect. Then,it stopped,and it did not fade away just one second noise then nothing. SO...here I am on vacation. This now happens every few times we start it,not every time,only when it's stone cold,it gets faster with RPM's , yes the oil level is fine,however there is one anomaly...it reads overfull,and has for the last two changes( it never did before).What do you folks think? Stuck valve,collapsed lifter,scored cam? Think I should try some sea foam or marvel mystery oil? Thanks let me know if I can provide more info...I can only do so much this week since I am like 600 miles from home Thanks!!

clockwise

when i was at nampa for my oil change for my rig which is a 95 Grand v8 was required only 5 q soo idk if that could be it and you put to much in? also kinda sounds like maybe something fell in?

jyaughn

my 5.2 does the same thing. not sure why

chris015

id try some marvel oil...and im in greenville too! small world eh?

jyaughn

i have tried lucas but it didnt help

clockwise

are we taking about a ticking? or a knock?

jyaughn

mine sounds more like a knock. but it dont do it all the time

iateeple

It is a "tick" or "tap", def. not a knock. It's a 4.0 and per the owners manual requires 6 quarts,and has always read normal with that much till recently. Chris, yes it is a small world (funny you should phrase it that way since I am at Disney right now..) Whereabouts in Greenville? I am in Simpsonville. In any case the mystery noise did not happen at all yesterday. I am thinking must be a valve tap or a lifter pumping down. I will try some stuff and get back to you all.Thanks for the replies!

clockwise

sometimes on my XJ which was a 6 and if im right the motors are basicly the same.... and the valves would tick and it had around 80k

djb383

I think it's an ageing lifter that is loosing it's oil prime, when the engine is off for a while. The oil leaks/drains out of the lifter when the engine is off and refills after starting the engine. Not really a big deal as long as the ticking disappears after the engine runs for a bit.

skiebuster

Mine did the same thing after it hit 120k. at 190k I changed my oil and it really started knocking. Then it blew. Faulty piston skirt. yeah it sucked.

iateeple

kind of what I suspected, lifter going...hope it's not a faulty piston skirt! I drive a cherokee,and to me 190k is just broken in,but I assume these Grands can't go quite as long due to the added weight. Still, If this thing doesn't last to at least 200k,with all the preventative maintenance i have put in, I will be dissapointed. I believe I will try seafoam and a 5W-30 oil with more zinc/phosphouros for the winter. See what that does. The noise scared me a bit but has not reappeared.Odd.Dang 40 year old valvetrain design

yankeebikachic

Mine does it too, only when very cold, and it stops after a couple of minutes. It has done that for forever. You may not have noticed it until recently, most of us get in our autos and shut the door and have the radio on or kids yakking. But do make sure it is not overfilled!

00xj-classic

MY 00 xj did this for a while..I dont know what it is..? My 93 also has a little tap knock.. a couple days a go i started my 00xj, Its been sitting for 3 months in a garage.. The noise is gone..I also switched to 10-40 before storing it.. MY 00 also has a very LOUD valve train on accelaration. I always thought it could be a sticky lifter or no oil getting to the lifter...

iateeple

Ok it continues...Does not do it every time you start it, hot or cold start seems irrelevant, and it is LOUD. My father heard it inside on the second story of our condo..he said it sounded like a woodpecker on metal...5 seconds later it's whisper quiet.Anybody got any TECH for me? any tests to be done?