Problem Noise... Not much info

bbwilson · 09-25-2009, 08:35 AM

I'm going to do my best to describe this noise and see what you guys think it might be.

1. It is coming from what sounds like the back the tracker (gear shift back)

2. Seems to happen more when the tracker is bogging down(to high of a gear) or sometimes while shifting (makes you think transmission, u-joints, something)

3. The sound is a loud rattling, it reminds your of a heat shield or something that has came undone and it just beating or vibrating against a cat or muffler (this is not it i check)

4. i have replace gear oil, it was very low.

I know that i don't have alot of info, but maybe someone has had or heard this before, i really don't know what it is... trow-out bearing? u-joint?. I wish i could record the sound and put it on here because it's not explained very well. But i'm having a hard time narrowing down the placement while driving.

on a happier note i got the front crank seal put back in, and while at the 4x4 jamboree i picked up a set of bran new still had the stickers 30x9.50x15 BFG M/T for $300... sweet!...and my tracker looks and performs amazing.... with a little rubbing on the inter fender.

Nor'Easter · 09-25-2009, 10:47 AM

What gear and at what RPM?

If you are in the wrong gear (too high a gear and too low RPM`s) and it doesn`t do it when in a proper gear, well,, I think it`s obvious as to the cure.

Have you ever seen what the motor does when in the wrong gear? It wiggles and squirms like a stuck pig. This, in turn, rattles the whole exhaust system and drivetrain and somewhat the whole vehicle.

The rattle you are trying to find could be one of many things with part of the exhaust system being the more likely culprit (including hangers) but the actual culprit is being in the wrong gear for your road speed (ie, RPM range).

With my 16vlv 4dr 5spd, I can have low RPM`s (near idle speed) in first and second, but as I climb up the gears from there, 1500 RPM or above is needed if I want to accelerate without lugging (shake, rattle and rolling) the engine. In fifth I like 2K RPM as a minimum. More-so, if I am facing uphill.

There is a difference between bogging down (engine malfunction) and being in the wrong gear.

If you just want to find the rattle so you can fix it, put your E-brake on hard, choose second or third gear and try to `go` with someone under or nearly under to help listen to where it is coming from. Be very careful not to run helper over!!!

I have also brought the bumper (non-airbag car) snugged up to a brick building (or other strong resistance) and used the wall as a stop under acceleration to be able to apply drive train torque to find issues such as U-joints or other clanks or under load engine issues... You could also use safety tow chain or strap if need be. Just be careful, try first without anyone under.

bbwilson · 09-25-2009, 10:54 AM

Forgot to mention i just had exhaust redone a month or so ago? I do understand that it makes sence that it makes noise when in wrong gear, i would just like to know from where it's comming from. Thanks for the input on this Nor'

tusong200 · 09-25-2009, 11:00 AM

You sure it's not just 'pinging'?

bbwilson · 09-25-2009, 11:32 AM

Quote:

Originally Posted by tusong200

You sure it's not just 'pinging'?

What do you mean by pinging... it sounds like there is a little man down underneath there with a hammer beating the time out of something really fast ha

.

Nor'Easter · 09-25-2009, 11:34 AM

Only way to know is get it on ramps and follow it to the source.

That`s one thing nice about my GMC 1500. I can use a creeper to get to underside without it being on ramps. The Kick is so low my cat has to scrooch down to get under it!

Pinging is piston slap. Sometimes a high pitch, other times a loud clackity noise from wrong octane, timing too far ahead and sometmes loading down the motor and trying to accelerate from wrong gears etc...

Little man with hammer would be ``peening``

tusong200 · 09-25-2009, 12:34 PM

Quote:

Originally Posted by bbwilson

What do you mean by pinging... it sounds like there is a little man down underneath there with a hammer beating the time out of something really fast ha

.

'Detonation' or 'pre-detonation'. The sound is the piston tops rattling. Not at all unusual when accelerating in a gear too high with an old engine. Also will occur if an older engine is running too hot. Try a tank of high octane gas and see if the sound goes away or at least doesn't occur as often.

bbwilson · 09-25-2009, 01:34 PM

Very well could be... but think further back, the noise i hear is behind the drivers seat. I'm not saying the noise is getting worse, but i am paying more attention to it. It does happen between every shift and when in to high a gear.

Better analogy the little man now has a food processor with nails in it, and he will turn it on slow, then speed it up, then stops it, them fast again... not a constant volume but a constant noise. Like metal on metal vibrating and rattling , but it's not gears grinding. (i think i might TM that analogy so use it while you can)

I'm really struggling here to find a way to explain this noise - it's loud enough to totally overwhelm the radio (so I can't just turn it up and make it go away).

riley · 09-25-2009, 03:56 PM

Do you have the noise when driving or is it there when at idle as well?
You said the gear oil was low, transmission or rear differential?

Try palcing the rear on jack stands and rotatin the wheels by hand you may be able to pin down the noise that way. If you off road very much you may have chipped a gear in the rear end.......good luck