Thegdog

Hi everyone,

I have a 1999 Grand Cherokee and I have a weird issue with it. When going through the drive at a fast food restaurant I heard a clicking sound, it changed with the rpm of the engine (faster). Here are the conditions and a video link

1.- The clicking noise doesn't start until I shift into drive. But once I drive it and warm it up, it doesn't matter what gear its in.

2.- Seems to be coming from accessory belt or top of engine cover.

My jeep has 140K, 4.7 V8, automatic tranny and full time 4x4/

Seems to run fine, no loss of power. But I don't want to damage it, and its my only car.

My asked my mechanic over the phone about it, he said it might be an exhaust leak, but if that were the case would I hear it at the front of engine? At the time I talked to him, I had not yet discovered it was coming from the front of car. You can also hear it in the back exhaust pipe.

http://www.youtube.com/watch?v=OF9OS...ature=youtu.be

dublove

are you sure its coming from the engine? definitely make sure. put it in park, and rev the engine and listen. if no clicking, its not the engine. if its ONLY in drive, then im 99% sure its drivetrain.
if its from the front end, id be ballsy enough to tell you straight up, its the pinion bearing in the front diff.

same vehicle here, same motor, just cured the same issue.


edit:
sorry, not the pinion bearing, ignore that.
have you gone offroading at all? and what driveshaft do you have?
i did have this same issue but it wasnt my pinion, though that did have to be replaced later.
it turned out my driveshaft was blown. if you have the CV style shaft front to back, its likely that the front joint is all screwed.

Thegdog

Its most certainly the engine, or something on the accessory belt. It makes the noise when I rev it in park.

dublove

ok, well if thats the case id be confident in saying its a sticky lifter. or something loose hitting the belt/fan.
check for anything loose or dangling, close to any moving parts, something that could be vibrating a whole bunch.
if nothing, then try running some seafoam through it and see if the clicking quiets or goes away. seafoam helps with sticky lifters

Thegdog

I actually got some seafoam yesterday, would I put it in the oil fill line? Is it safe to drive, damage possible?

also did you see the video link? just wanted to check in case you didn't see it.

And thanks for all your help on this!!!

dublove

i didnt watch the video, my computer takes long enough to load a page just to post something lol.
but ya seafoams safe, no severe damage will occur. the ONLY bad thing i ever seen come from using seafoam in the oil, was it opened up a leak in my rear main seal. but thats one case that i know of. ive never heard any bad things from anyone else. i work at a parts store and hear all kinds of stuff.

now, keep in mind its recommended to use it at least 50-100 miles before an oil change, because its going to clean the HELL out of your engine. and you dont want all that sludge floating around for long.
but if you do use it, its 1 1/2pints (i think its pints?) per quart of oil your engine takes.
so you take 6 quarts of oil, seamfoam comes in 10pint bottles, thats about 8pints? youd be safe using the whole bottle. i have, no issues.
just open up the oil cap, pour it in, and drive away. can also be used in your gas. pour a whole bottle in the gas.

seafoams a very well respected product, that and lucas products.
would never recommend something i dont personally use/trust

Thegdog

Thanks, but I think I need to rephrase my question. I am not worried about the seafoam, but rather damage from whatever is making that sound. My question should have been.

"Am I doing harm to my engine, by driving it with the clicking sound?"

Sorry about that.

And just my luck, the oil was just changed today.

dublove

if it is indeed a sticky lifter, its not that bad.
but, i dont recommend driving it like that for too long. i dont think you will be replacing the engine if you do, but you may just have an extra problem to pay for.

since your oil was just changed, just pour that seafoam in your gas tank, head to advance auto or something, and grab a lucas oil product. i forget exactly which one it is, but one of them helps free up sticky lifters and is safe to drive with until your next oil change. there are other products as well that help the same issue, some may work better than lucas, some may not. i certainly havent tried them all.
one i keep hearing about it called instaquiet or something, its in a red bottle.

keep in mind, many people will scoff at the idea of using additives. im sure ill be told how much of a moron i am for suggesting them. but hey, sometimes we cant afford 8 hours of labor in a shop. some of these products do work.

97zjnoob

There are directions on the seafoam bottle follow those minus putting it in the oil since you just changed it. Im also a fan of lucas oil products. I used the oil stabilizer. A little less than 1/3 of a bottle in my 97 with the 5.2L and it purred once warmed up. Its kinda expensive. About 12 bucks a bottle, but its lasted me a while. Just make sure you dont overfill the crankcase.

KF2M

Sounds like a lifter tap. You could poke around (careful around moving parts) with an engine stethoscope to isolate where the noise is coming from. You could have a partially collapsed, or leaky lifter.

Thegdog

So I started the jeep up this morning, and no sound. I revved it up really hard, no sound. I am going to bet that as soon as I put the car in drive, it will make the sound.

It has nothing to do with the car being warmed up. I could swear that the sound is coming from the valve cover, but I guess thats not a great possibility being that it must be put in drive first. This is very strange!

KF2M

Probably happens in drive since the engine will turn slower in turn lowering your oil pressure probably just enough to not fully pressurize/fill the lifter. Could possibly have a blockage someplace as well.

Thegdog

Ok, update on the sound. The sound comes on totally random, and has nothing to do with what gear its in. That must have just been a coincidence. Its there 90% of the time, but sometimes (especially when I cold start it) the sound doesn't exist. Not sure if that too is a coincidence. But when I reach my destination, its there.

Is it possible to be something with the power steering pump? It is close to where the sound is coming from.

I am going to take it to my mechanic Monday and have him take a listen, I shall report back on what he says.

Thegdog

So I took it to my mechanic last week for him to listen, and got news I did not want to hear.

Basically these engines have a lubrication issue, which according to the internet is due to using the wrong oil and not changing it at proper intervals. He pointed out that there was also a low end knock sound. So he said I will need a new engine.

I asked him what the cost would be with labor, he said about $4K for a jasper. However I went online to jaspers website and the cost listed is $3600. I am not sure how he can put it in for $400 unless he gets a discount from jasper (which is possible).

I was told I should get a second quote on the engine install. Talked to another guy that I really trust. He said he could install a used engine with a 2 year/unlimited mile warranty for $4200. The $4200 is including all costs.

Considering the $4200 option, would give me 2 years worry free on my engine and I could have the extra money in the next 4-6 weeks.

I have stopped driving it after the low end knock got worse on my way to work. I turned around, went back home and got a different car.

jeepcherokee99

Just get a new car period. Even if u replace the engine it will happen again. The 4.7 r known for going bad... IMO