loud metal hitting metal noise under the vehicle

[79NCFJ40]

My 1979 FJ 40 just stated making a loud noise under the vehicle. It might be the transfer case. The case is leaking a little bit now and it never has before. The noise doesn't happen when I am driving under 5 mph. It gets very loud when driving faster. The noise sounds like a metal hitting metal that is rotational in nature. It's almost like a piece of metal is out of place and not meshing correctly as it revolves. If I push the clutch in and roll slowly down a gradual grade it doesn't make a sound. Any ideas? I don't know if it matters, but this FJ came from Columbia, South America. Thanks.

 

[Downey]

See if transfer-case has a crack, thus leaking, and having gears out of alignment ???

 

[Tancruiser]

I would look at all your U joints . Is this in two wheel drive or four?

 

[79NCFJ40]

See if transfer-case has a crack, thus leaking, and having gears out of alignment ???

ok, thanks. I'll take a look

 

[79NCFJ40]

I would look at all your U joints . Is this in two wheel drive or four?

It's a 4 wheel drive. The U joints look good.

 

[CRZR45]

Any play on the output shaft of the transfer case or at he pinion? Maybe loose pinion nut

 

[65swb45]

You probably have a broken tooth in something, most likely rear end or transfer case. The only safe thing to do at this point is to pull covers and inspect. Don’t drive unless your an expert on driving vehicles that suddenly lock up.

 

[45Kevin]

"Looking" at u-joints is not the way to check them.

They need to be unloaded so you can move them.

But like Mark said, it is probably not a u-joint.

 

[JohnnyC]

Does it make the noise still if you put the transfer in neutral

 

[79NCFJ40]

I would look at all your U joints . Is this in two wheel drive or four?

Here are some picture of the transfer case and the universal joints near the case.

 

[79NCFJ40]

I don't see any cracks in the transfer case but if you can, please let me know.

 

[WDT Siri]

May be due to the absence of a Tranny to Transfer by pass hose, oil has run out in Transfer case & has caused an internal damage.

 

[middlecalf]

Clutch in, no sound. I would start there.

 

[ToyotaMatt]

another often Overlooked area of inspection Focus Point should be , Both your Companion flange Tin dust shields , they can rattle like

a Loud Bear Bottle Sound , or metallic too

like @middlecalf pointed out push in clutch no sound , start there Yes , but inspections and verification's done your yourself

are usually free , Mis-diagnosises are usually Not



good luck

 

[79NCFJ40]

Any play on the output shaft of the transfer case or at he pinion? Maybe loose pinion nut

no, there isn't any play front to back. there is a tiny bit of play side to side.

 

[79NCFJ40]

Clutch in, no sound. I would start there.

ok, thanks. I'll take a look

 

[79NCFJ40]

Does it make the noise still if you put the transfer in neutral

damn, I don't remember now. I guess I could drive it up the road a little bit but I fear I would be damaging it more.

 

[Living in the Past]

Not sure I've ever seen a later nineteen spline output shaft used to add a split transfer case on a pre 8/80 housing. 8/80 the start of the split case the transmission had a crossmember under it.

 

[79NCFJ40]

another often Overlooked area of inspection Focus Point should be , Both your Companion flange Tin dust shields , they can rattle like

a Loud Bear Bottle Sound , or metallic too

like @middlecalf pointed out push in clutch no sound , start there Yes , but inspections and verification's done your yourself

are usually free , Mis-diagnosises are usually Not



good luck

It took the shield off to inspect the transfer case. it wasn't loose. I wish that was the answer though. I'll look at the companion flange. Thanks.

 

[JohnnyC]

You do not have to drive it... putting the transfer case in neutral makes it so the tranny spins