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-   -   Start-up clunk? and some other basic Q's (http://www.jeepgarage.org/f204/start-up-clunk-and-some-other-basic-qs-59031.html)

Bushmaster69 04-25-2013 09:39 PM

Start-up clunk? and some other basic Q's
 
Ok, Got an '02 GC Larado 4x4 stock 4.0 with no mods, that i'm aware of.

When the engine is cold right when the engine fires there is a obnoxious clunk or bang. It's not as noticeable when the engine is at operating temps, but still there, but only at startup.

Any ideas?

Now the basic Q's

I'm not sure of the transmission ID as it's dark right now, I suppose I could wait till morning to go look but... :)

I want to service the trasmsmission (since I have no idea when or if it was ever done) When it's cold it doesn't shit very well, rpms gotta be around 1700 -2000 depending on what mood she's in. What are the owner/operator/performance guy recommendations on fluid type, filter(s) etc. - Including the front and rear transfer cases - in the reasonable price range please?

Also -( geese this guys got a lotta newbe Q's) What are the thoughts on these performance "chips" for engine and transmission?

As always, thank you in advance! (Whatever happened to Please and thank you anyhow?) :)

Frango100 04-25-2013 10:00 PM

Re: Start-up clunk? and some other basic Q's
 
Quote:

Originally Posted by Bushmaster69 (Post 811797)
Ok, Got an '02 GC Larado 4x4 stock 4.0 with no mods, that i'm aware of.

When the engine is cold right when the engine fires there is a obnoxious clunk or bang. It's not as noticeable when the engine is at operating temps, but still there, but only at startup.

Any ideas?

Now the basic Q's

I'm not sure of the transmission ID as it's dark right now, I suppose I could wait till morning to go look but... :)

I want to service the trasmsmission (since I have no idea when or if it was ever done) When it's cold it doesn't shit very well, rpms gotta be around 1700 -2000 depending on what mood she's in. What are the owner/operator/performance guy recommendations on fluid type, filter(s) etc. - Including the front and rear transfer cases - in the reasonable price range please?

Also -( geese this guys got a lotta newbe Q's) What are the thoughts on these performance "chips" for engine and transmission?

As always, thank you in advance! (Whatever happened to Please and thank you anyhow?) :)

Regarding the engine noise i donīt know. Maybe a sound clip could give an idea.
Since you have the 4.0 engine, it should have the 42 RE transmission.
Recommended fluid is ATF+4. Can be that fresh fluid and filter will improve the shi(f)ting (:D).
I expect that there are no Vari-loks in the diffs, the front diff needs 75W140 and the rear diff 80W90 (for normal operation) or 75W145 (for towing).
The t-case depends on which type it has: the NV242 uses ATF+4, while the NV147 uses mopar P/N 05016796 ( = Mobil 424 fluid).

Bushmaster69 04-26-2013 01:48 PM

Re: Start-up clunk? and some other basic Q's
 
Thanks for the reply, I'll see what I can do about the sound clip. Didn't think of that, if I can pick it up - its plenty loud enough but recording it might prove a little difficult. :)

BTW, I glad you figured out that I meant diff's and not transfer cases since theres only 1 ;) and didn't give me hell for it...lol :)

Frango100 04-26-2013 09:47 PM

Re: Start-up clunk? and some other basic Q's
 
I just remember that on my jeep on the front diff a plate calls for 80W90 instead of the 75W140 from the manual. I have 80W90 in both diffs.

kennzz05 04-27-2013 12:59 AM

Re: Start-up clunk? and some other basic Q's
 
how bout motor mounts on the noise issue

Bushmaster69 04-27-2013 01:55 PM

Re: Start-up clunk? and some other basic Q's
 
OK, I have two sound clips the first one is from inside the jeep http://www.filedropper.com/jeep notice right as it starts and right as it shuts down. The second clip is from inside the engine compartment. http://www.filedropper.com/jeep2

The interior seems to amplify the noise. I was thinking about the motor mounts being the cause, but not really sure how to test them, engine is kinda heavy to just grab it and shake it, and there isn't a lot of room to use a prybar. Any ideas?

Frango100 04-27-2013 02:10 PM

Re: Start-up clunk? and some other basic Q's
 
Didn't hear any clunk:confused:.
Don't know the 4.0, but can't you see the engine mounts? The engine is hanging in rubber, so check if you see any deterioration of the rubber block.
When the mount(s) are worn, you normally get noise when accelerating.
Did you check the exhaust if its not touching anywhere?

kennzz05 04-28-2013 05:11 AM

Re: Start-up clunk? and some other basic Q's
 
put the jeep in drive and have someone stand on the side of the vehicle with the hood up while they are watching the motor, apply the throttle while holding the brake pedal at the same time. (in the old days this was called power braking, to spin the tires) see if you get any major movement of the motor. i know on my xj the motor would move towards the passenger side like probably a few inches heres some videos that might help

Jeep Engine Mount Replacement Guide - YouTube

and this one actually shows the engine moving upon throttle application
ZJ with broke motor mount - YouTube

Bushmaster69 04-28-2013 12:35 PM

Re: Start-up clunk? and some other basic Q's
 
I can see the mounts from the top, but cant get a good visual on the rubber. the sound clips have the noise, but it depends on what program you use and the EQ settings. I used Wavepad Sound editor, which gives me a visual audio wave pattern. I can see the noise as well as hear it. heres two images, the highlited areas is the noise. At start up it lasts foir about 2/10ths of a second and shutdown about twice that.
http://img.photobucket.com/albums/v4...jeepwavpic.jpg
http://img.photobucket.com/albums/v4...epwavepic2.jpg

Bushmaster69 04-28-2013 12:38 PM

Re: Start-up clunk? and some other basic Q's
 
I'll try power-braking it, never though of that... Thank you - everyone. :)


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