Jump to content

Recommended Posts

Posted

My truck (92 1500,2wd w/5.7L) has developed a wierd and annoying noise in the last 100 or miles of driving.

It's a loud rattling/tapping that sounds like it is coming from the front driver's side of the truck, it has a very metallic quality to it.

It only happens when the truck is gear and the accelerator is pushed, it seems loudest when the motor is at about 2000-2500 rpm and actually seems to get quieter beyond that point (although the engine may just drown it out at higher rpms).

It only makes the noise when the accelerator is pushed while in motion, if I take my foot off the gas it stops immediately. It doesn't make the noise when rev'd in park or neutral only in drive while in motion. The degree to which the steering wheel is turned or not turned seems to have effect on the presence of the noise.

The truck has 204000 miles on it, I've only been the owner for 4000 of those. The vehicle was previously used as a farm truck and probably saw some semi-abusive use there.

I'd really appreciate any opinions or know how on what's making this noise. I've had wheel bearings go out before on a different vehicle, but this isn't really the same noise or conditions causing the sound. I'm pretty stumped. :confused:

  • Replies 46
  • Created
  • Last Reply

Top Posters In This Topic

Posted

Symptoms unfortunately got worse today.

I drove to work and back (about 20 mile round trip), the noise continued and I also had noticeable loss of power going up a couple hills.

I managed to shoot a short video on my phone, which was precarious since the truck really has to be in motion to hear the sound. Although I can briefly replicate the noise to some extent in park. I'm leaving the truck in drive-way until this gets sorted out.

Posted (edited)

Pull the valve covers and check for a broken or cracked rocker arm, sounds like that's what it is, they can break on a moments notice. If a rod was hammering that hard the engine would have very low oil pressure, would likely be smoking like a steam ship, and probably would have already quit by now, so I doubt it is a rod bearing. The 350 bottom ends are about as bullet proof as they come so it would be very uncommon for anything in the bottom end on these engines to let loose just like that under normal driving on a daily basis, that is unless you had REALLY abused it with some very high and prolonged RPM's over and over which I doubt you've done.

 

If all the rocker arms are fine, it could also be a collapsed lifter. Get the valve covers off, go over each rocker arm carefully looking for one that's loose. If you find a loose rocker arm that appears to be intact, then you've got a collapsed lifter and possibly a bent or damaged push rod as well as things were likely banging into each other with all the excess clearance. Look the parts over closely for damage before you decide to re-use them. Unfortunately a collapsed lifter that refuses to pump up will require removal of the intake to replace it. An old trick to free up the lifter is to add about a quart or so of kerosene to the oil and let it idle for a few minutes, if that doesn't take care of it the intake is going to have to come off to get at the lifter. If the kerosene trick does work you're going to want to change the oil ASAP.

Edited by ifixedit
Posted (edited)

Thanks, hopefully I'll get to fool with it some in the next fews days. We've just been using my wife's car for everything in the mean time.

We've got our first baby due in less than four weeks, so I've been pretty short on time and money to mess with this recently.

 

At my wife's request, I did change the spark plugs this morning to see if that made a difference. I hadn't changed them since I got the truck and had no idea how long they had been in (looks like a long long while). the new plugs haven't changed the tapping noise at all, but have brought some power back into the truck.

 

I know you can supposedly "read" plugs, and I've got the chart to look at for it. I also took pictures of each plug by cylinder to get opinions. Other than they were obviously "vintage", does anything else stand out?

12141666_10153045267301881_3663325299155

Hopefully I can take the valve covers off later this week and check out the rocker arms.

I also have a question, "What is this and should it be connecting to anything?". It was underneath the air intake pipe/silencer box when I pulled them out.

12122492_10153045289741881_5962028296346

Edited by jstange
Posted

How is your oil pressure during the times it "taps". Sounds like it could be a drop off in oil pressure??

The oil pressure never drops during the tapping.

 

At idle pressure is a little about 30 and when I'm on the gas it goes up to about 45.

Posted

What happens when you power brake it around 2000 to 3000 RPMs? I would try that and have someone listen under the hood. Also check and see if you fan is hitting the shroud.

Posted

What happens when you power brake it around 2000 to 3000 RPMs? I would try that and have someone listen under the hood. Also check and see if you fan is hitting the shroud.

By "power braking", do you mean putting it gear and standing on the brakes while revving the engine?

 

If so I haven't tried it.

Posted

By "power braking", do you mean putting it gear and standing on the brakes while revving the engine?

 

If so I haven't tried it.

Yes. But when you do this you have to use common sense. Make sure your brakes are good and able to hold at those RPMs and make sure you are no where near something that you could run into in case your brakes let go. And you might have someone standing near the truck so they could hear where the noise is coming from.

Posted

sounds like a sticking lifter. had it happen at about 120,000 miles on my truck. Ran a cleaner through it purchased at the local auto parts store, changed the oil per instructions, and it solved the problem.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    250.5k
    Total Topics
    2.7m
    Total Posts
  • Member Statistics

    342,897
    Total Members
    8,960
    Most Online
    ncleg
    Newest Member
    ncleg
    Joined
  • Who's Online   6 Members, 1 Anonymous, 831 Guests (See full list)


  • Latest Articles

  • Posts

    • Thanks to the convenience of Amazon, I was able to get a few things done to the truck today.  I installed Carquest Premium oil and air filters with five quarts of Mobil1 High Mileage 10-30 along with a quart of Pennzoil Platinum 5w-30 I already had.  The latch for the flip up center console lid was broken so I replaced it along with the power mirror switch.  I found my push retainer assortment this morning and reattached the plastic under the bumper and it was only held on with a few screws and retainers.  Then I programmed a new remote keyless entry fob so I can lock my dog in the truck when I take her out with me (I've got to keep the air going for her since it's been in the 100s).  Finally, I ordered some LED interior bulbs and replaced the reading lamps.  The front lights are working fine while one of the back lights only works intermittently and the other not at all.   While under the truck, I found the source of at least one of the noises: the sway bar links need replacing.  I ordered a set of Suspension Dudes links with Code Red bushings.  Never heard of them, but they're made in the USA and have decent reviews.  While making yet another Amazon order, I went ahead and added a set of front tow hooks.  I went with red, since that's the color of the sway bar link and bushings and it should look decent enough on a black and chrome truck.  Speaking of which, it doesn't bug me much, but the passenger side mirror has a chrome cap while the driver side doesn't, so eventually I'll make them match one way or another.  Oh, and I ordered a $20 TPMS reset tool.  No idea if it will do anything for my sensors but it was cheap and will work for the Ford Transit Connect as well.     For tradition's sake, I ordered a new oil change wrench.  I kept the Snap-On 9/16"x15mm GM wrench I bought when I was 18 in the 2006 GMC from the time I bought that truck until the truck was lost.  While I was tempted, there's no need to spend $80 for a new SO wrench, or even $50 with shipping for a used one on Ebay.  I just bought a Duratech 15mm extra-long ratcheting wrench to do the job as needed.  It works, and if I like that wrench enough, I'll buy the set.  
    • The recall is for exactly this issue - those drain holes combined with the limited environmental capability of the tailgate electronics card inside the tailgate were a problem. The “safety issue” was the potential for the tailgate to spontaneously open, but all kinds of tailgate misbehavior can occur from water contamination of that control card.    There is no real fix yet. The initial recall just disabled the tailgate. Later, when parts became available, they would replace bad parts with new parts of the same bad design. My dealer is going nuts because the few times I let them get their hands on my truck, my tailgate is off due to a slide-in camper installation. They really want to cut my tailgate wires, but I won’t give them the chance. I will let them get their dirty hands on it when a real fix (redesign) is available.  My tailgate, which works just fine with sealant plugging the drain holes, will remain safe in a dry storage crate until then.  
    • Yes your absolutely right, I been looking at the 4 inch BDS one and it acutely states you can use the stock 20’s just not the 17’s or 18’s, I also didn’t realize that with my 275/60r20 stock wheels I’m already running 33 inch diameter wheel setup lol so I can just run my stock wheels and tires atleast to start.
    • I would expect that to be lift-kit dependent.  If the kit has interference issues w stock wheels, then the kit/manufacturer should indicate that somewhere.
    • That’s what I’m wondering is if the stock backspacing of the factory wheels will clear new upper control arms and such  
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...