Hello everyone just last night and today I noticed some knocking sounds coming from my 94 cruisers while driving. They seem to be coming from the front right wheel from about 900 rpm to 1500 rpm before they smooth out. They don't occur in neutral on the gearbox or in drive with the transfer case in neutral. Also when I put it into Drive it drops to 300-400 rpm. The Air-Fuel ratio lean malfunction seems to be coming on sometimes too.
Knocking sound coming from front right wheel while driving (1 Viewer)
- Thread starter NelsonCruiser
- Start date
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What year?
How many miles?
What recent service has been done in the last 10K miles?
- Thread starter
- #3
it is a 94 with 255k I am a new owner of this but have had the alignment done and the knuckles greased. Both axials have been rebuilt within the last 40k
- Thread starter
- #4
All bearings have been done on the engine as well
Look for an exhaust leak. Sometimes they sound like a mechanical knocking. Especially since you're getting lean fault as well. Could be an O2 sensor has come loose and goes in and out of the hole (this happened on mine)
Could also be loose wheel bearings. Jack up front axle and wiggle at 12/6 to see movement.
Could also be loose wheel bearings. Jack up front axle and wiggle at 12/6 to see movement.
- Thread starter
- #6
Awesome will do thanks for your help I assume just start at the manifold and work my way back checking all of it I will also post a video of the noise
- Thread starter
- #7
I didn't see a exhaust leak. where are the o2 sensors? Also, I don't hear the knock in park so would that still be a exaust leak.
An exhaust leak may not make a sound until you are working the engine
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- #9
Ok I can't put a video on here so here is a youtube link I just uploaded It might not be available to watch for a minute as it is still uploading
If it were me I'd start with checking lug nuts, wheel bearings, and brake calipers bolts.
From there move on to exhaust mounting hardware and suspension bushings, don't forget looking at the upper shock mount, they make a heck of a clunk when they shift around.
From there move on to exhaust mounting hardware and suspension bushings, don't forget looking at the upper shock mount, they make a heck of a clunk when they shift around.
- Thread starter
- #11
Thanks, I think I've narrowed it down to the exhaust If I hold the brake in Drive and rev to about 1200 rpm I get the same noise. There are some skid plates and protection to stop the cats from being stolen I think something is rattling around in there, with an exhaust leak in the same location.
lumbee1
Native American
1994 exhaust went up and over the frame rail. Since the knock is not a hard metallic knock and more damped, your exhaust could be hitting the floor under the passenger side seat. The floors have sound dampening panels glued to them from the factory.
You can have someone feel the floor for vibrations to confirm or once the exhaust is cool inspect for one finger of clearance around the pipe.
You can have someone feel the floor for vibrations to confirm or once the exhaust is cool inspect for one finger of clearance around the pipe.
- Thread starter
- #13
I need to check the exhaust better but after more research I also think it could be a warped or cracked flexplate
Any way you can have someone do what you're doing behind the wheel while you are under the truck for a look see?
With the truck on jack stands of course.
- Thread starter
- #15
I'll try that sometime tommorow
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- #16
Fixed! Turned out to be the cats hitting against a steel guard. Started after I washed it so it must have knocked out any dirt and mud keeping it insulated.
Put exhaust Wrap on it and the noise is gone
Put exhaust Wrap on it and the noise is gone
