Prado Wobbly Transfer outputs and Harsh Noise -Advice Wanted

[IcedJohnno]

Hi All
My KZJ-71 Prado has had wobbly Transfer case output flanges for some time now. The front flange bearing is quite rough. I regularly check & top up the oil as it does leak a bit. I try to run the oil level high in case too much leaks out between check intervals.

The last trip south to work at Round Hill had me at my usual speed along Thompsons Track. About 15 mins into 140 + km's, I rolled off the throttle and heard an unusual harsh noise as the truck momentum transferred the load back onto the engine. The noise may have been from the rear diff but probably came from the T-case. It was much louder & harsher than normal and may have been like a bearing race seizing. This happened several times in a row, upon testing, so I slowed down and drove nearer Mr Plods desired speed.

5 days and another 450km's later I am back home. Try as I might but I have not been able to replicate the noise on the slower return trip, nor today whilst trying to decide where the noise was coming from. (Back to higher speeds but not over the 15 minute distance required to heat-soak components)

Is it likely to be the transfer case?

What damage does the wobbly output flanges cause inside the T-case.

How much work to replace output flange bearings etc in T-case?

If I leave till later when I have more time, will I cause bad damage?

Am I likely to have a major break down on-route to work (600km round trip with 1 hr at 80 to 100km/h in Hi 4wd)

I am back in town for a week, doing the Mech. Design on my Ski Tow for Round Hill from home. I won't have a lot of time to look at this issue myself, and as usual funds have priority elsewhere...

All knowledgeable advice appreciated
cheers John

[Pedro]

Hi All
My KZJ-71 Prado has had wobbly Transfer case output flanges for some time now. The front flange bearing is quite rough. I regularly check & top up the oil as it does leak a bit. I try to run the oil level high in case too much leaks out between check intervals.

The last trip south to work at Round Hill had me at my usual speed along Thompsons Track. About 15 mins into 140 + km's, I rolled off the throttle and heard an unusual harsh noise as the truck momentum transferred the load back onto the engine. The noise may have been from the rear diff but probably came from the T-case. It was much louder & harsher than normal and may have been like a bearing race seizing. This happened several times in a row, upon testing, so I slowed down and drove nearer Mr Plods desired speed.

5 days and another 450km's later I am back home. Try as I might but I have not been able to replicate the noise on the slower return trip, nor today whilst trying to decide where the noise was coming from. (Back to higher speeds but not over the 15 minute distance required to heat-soak components)

Is it likely to be the transfer case?

What damage does the wobbly output flanges cause inside the T-case.

How much work to replace output flange bearings etc in T-case?

If I leave till later when I have more time, will I cause bad damage?

Am I likely to have a major break down on-route to work (600km round trip with 1 hr at 80 to 100km/h in Hi 4wd)

I am back in town for a week, doing the Mech. Design on my Ski Tow for Round Hill from home. I won't have a lot of time to look at this issue myself, and as usual funds have priority elsewhere...

All knowledgeable advice appreciated
cheers John

first thing i would do it drop the oil out of the transfer and see what comes out, if a bearing has seized there will be metal bits in the bottom of the case, oil in transfer will generally stay pretty clean on stock trucks. if there metal bits in oil then if you keep running it it will destroy itself eventually, if the oil is clean or black and no metal bits then slow down and put reasonable oil in until you get time to have a look see, check the nuts on the pinion flanges have not come loose,

cheers

pedro

[kbushnz]

The bearings are shot.

Pull it down and get them changed before you wear out any shafts....

Bearing kits are available.

Calvin