Where is the Most Unexpected Place You Discovered and Fixed a Rattle?

[1979 FJ40ish]

I know this is a Hail Mary, but here goes. I completed a frame-off restoration of my 79 FJ40 a couple of years ago, and it has recently developed a rattle when running over a bump or while on a rough road.

I have done everything I can think of to try to locate it, including but not limited to: rocking it back and forth, pushing it up and down, removing everything in the FJ that could rattle, removed the hub caps and checked the lug nuts. I removed the spare tire and checked all the doors. I’ve put it up on jackstands and crawled under it several times. I pushed and pulled on everything I could get my hands on and checked every fastener. I even removed the skid plate so I could check above it.

The rattle occurs while running in either 2x4 or 4x4 and while running in gear or neutral. I replaced the shocks and spring shackles during the restoration and just regreased them.

There has been no noticeable change in the engine, steering, transmission, or brakes, or any unusual vibrations.

As everyone who owns an FJ knows, there is no sound deadener or insulation in them, so the rattle seems like it is coming from everywhere.

Any suggestions on what I should try next?

Thanks

 

[charliemeyer007]

amazon.com/ZKTOOL-Electronic-Stethoscope-Diagnostic-Headphones/dp/B09QLXV61Q

 

[vipergrhd]

My only suggestion would be is have another person ride with you while driving, noise have a tendency to travel from one corner to the other.
There are tools out there that could help isolate the location of the noise.

 

[pb4ugo]

Hood hinge bushings. Put a section of rubber hose in the trough on the cowl where the cowl and the hood lip meets and see if the rattle stops of changes. The hose will put pressure on the hinge pins.

 

[rabid]

The most unexpected place was not only a bad thud noise/ rattle, and at the same time my heat was barely working while it was winter in Vermont.



Turns out my friend had taken off the little rubber boot from the heater duct and jammed a whole canned danish ham in there knowing I would find it when my heat didn't work.

This story is not helpful, I just wanted to throw it out there.

 

[GA Architect]

I chased a rattle for years....then found it by happen-chance, rear brake line was missing a clip. < Click Here >

 

[rex in bama]

Hood hinge bushings. Put a section of rubber hose in the trough on the cowl where the cowl and the hood lip meets and see if the rattle stops of changes. The hose will put pressure on the hinge pins.

This, along with replacing the little rubber fender apron bumpers, made a massive difference. Cured what I thought was a loose transmission mount. Also spray lubricant on your ambi door hinges and spare tire swing out hinge to see if that changes things.

 

[igotta40]

I used to have a really annoying noise coming from the passenger seat……

 

[Its me shaneus]

I had put in a fresh 2F, H55 and split transfer case. Early on a bump in the road started a persistent click. Finally tore into it. My home brew tunnel cover had a sharp metal edge that rubbed the top cover of the trans. Super loud and annoying.

Bump in road must have caused drivetrain to shift forward an 1/8”. Can see shiny spot in pic. About lost my mind!

 

[steffan]

I had a friend that worked for GM in the 70’s, they would get board on the line and for fun, they would tie a string onto a washer, then tape the string to the inside of the fender, knowing the new owner and dealer would go insane trying to figure out where the sound was coming from

 

[pbgbottle]

Hood hinge bushings. Put a section of rubber hose in the trough on the cowl where the cowl and the hood lip meets and see if the rattle stops of changes. The hose will put pressure on the hinge pins.

This fix is amazing. My hood rattle drove me crazy until figured if out and I put some rubber hose under on the cowl lip. Still awesome after like 20 years I put one piece under each hinge and a 6 inch piece right in the middle. Yep.

 

[pbgbottle]

Hood hinges rattle. ,glass in the doors can rattle ,rear of body if mounts rotten can rattle ,rear doors can rattle roll cage can rattle against the body sometimes. Holy s*** handle can rattle on a full cage of close to the front hoop ,seats can rattle , something under the gas tank cover can rattle. Loose bolt and washer can rattle. Transfer case shifter can rattle and or hit the body.

 

[rex in bama]

I had a friend that worked for GM in the 70’s, they would get board on the line and for fun, they would tie a string onto a washer, then tape the string to the inside of the fender, knowing the new owner and dealer would go insane trying to figure out where the sound was coming from

Pure evil!

 

[1979 FJ40ish]

Thanks for your suggestions

 

[lcwizard]

All my joints after 65 y/o. Still haven't found the fix

 

[msapers]

The most unexpected place was not only a bad thud noise/ rattle, and at the same time my heat was barely working while it was winter in Vermont.



Turns out my friend had taken off the little rubber boot from the heater duct and jammed a whole canned danish ham in there knowing I would find it when my heat didn't work.

This story is not helpful, I just wanted to throw it out there.

Actually, this story is HUGELY helpful. I have friends that need to be messed with. I'm off to buy hams.

 

[rkymtnflyfisher]

The bolt for the hardtop post behind the seats.

Speedo and parking brake cable rattling against each other, resonating through the firewall.

Blinker relay rattling on the body.

Sest belt female end rattling off the Tuffy console

The crankshaft pulley making a knock after the nut went MIA.

Fold down Front Runner rattling and knocking, the biggest culprit was the cheap plywood cutting board.

Shacke pin on the frame side, a bushing was shot.

I could go on and on, I spend a lot of time trying to eliminate knocks, rattles, and squeaks.

 

[65swb45]

Back in 1990 I went to my friend’s shop to borrow his pitman arm puller for a SBX rebuild (didn’t have my own yet) and he asked me to ride along in an FJ40 he had just finished an LS swap on (oldest LS swap I know of) because of a rattle he couldn’t track down. After about four blocks I told him to turn around and head back to the shop.

I got out the front, walked around and opened the aftermarket tire carrier (that prevented the ambi doors from opening) and proceeded to bang on the license plate holder, replicating the noise!

He had moved the plate to the aftermarket carrier, but forgot about the two floating, captive nuts still in the stock license holder.

 

[1979 FJ40ish]

My thanks to all who took the time to post constructive suggestions, and especially those who suggested the hood. You nailed it!!!! Now I can move on to the other squeaks, rattles, and thuds.

Thanks, guys!

 

[fireflyr]

I discovered a rattle leaving Booneville, CA last year after completely going through my 40. Was driving me crazy all the way out to the bridge at Highway 1. Ended up being that case of West Coast IPA I stashed in the back leaving the brewery. My brothers all pitched in on helping me fix that problem.