Transfercase Whine

[SalemRover]

I have noticed considerabley more transfercase whine from my series. I drive a series 3 2.5 nad with a SIII gearbox (suffix b), the early model roverdrive installed as well. I do not recall what suffix the transferbox is but I have never rebuilt it, and never run it dry.

After the tcase warms up a bit it whines in all gears with the overdrive engaged or disengaged. The whine is only present under load and when coasting out of gear or simply clutch down it is so faint as to be negligible. Driving to an event through heavy traffic and 5 hours of rush hour on 95 the overdrive leaked and it ran low, causing the whining to increase dramatically. I stopped to let it cool and add some gear oil before continuing on. Driving back this weekend I stopped to make sure I had plenty of oil, but even with that the whining was fatiguing even with earplugs in. I have my tuffy out and the center seatbox panel is loose and on the highway I can lift the cover and you can hear the whine from the tcase. I am pretty sure it is not the gearbox or differentials. This whine was present (just not as loud) when I ran the up to the winter romp without an overdrive one year. When I added the roverdrive I replaced the tcase sump with their finned al cover and the old gear oil was a bit dark with some small flecks of metal but nothing outrageous, and certainly no large chunks of anything. It is bad enough at this point that it needs to be addressed as I would not put anyone in their now for a long period without decent ear protection.

Before I start tearing into this can anyone think of other methods to further test and isolate the source of the whine? Also any and all advice is appreciated. Speak up though, my ears are still ringing.

Regards,

Jason Wachtel

[TeriAnn]

From your description I would suspect the bearings on the intermediate transfercase shaft. Especially since it is a B suffix box. They are poorly lubricated even when the oil level is where it should be. Run it low and you can get excessive wear. Your noise under load can be the extra clearance pushing the intermediate gear up from where is normally rides. If it were me I'd drop the transfercase pan, remove the intermediate gear shaft and replace the bearings & brass spacers. The A & B suffix transfercases have a smaller diameter shaft & bearings. It is one of the places that Land Rover strengthened starting with the C suffix transfercases.

[SalemRover]

Thanks TerriAnn. I will be able to tear into it later tonight, possibly tomorrow. Ill post what I find. It would be great if that is what it is as it seems it can be done is situ.

Jason

[SafeAirOne]

It would be great if that is what it is as it seems it can be done is situ.

That'd be nice, as it's probably the easiest thing to remove from the T-case without any substantial effort.

[SalemRover]

That'd be nice, as it's probably the easiest thing to remove from the T-case without any substantial effort.

Except for gear oil! Definitely looking long in the tooth. Can easily feel the raised edge on the gear with my fingernail.


8643

[NC_Mule]

I have very little experience tearing into trannys/tcases or diagnosing them. When you find a gear that's "long in the tooth" is that a classic.....oh yeah this is where the noise is coming from?
pb

[stomper]

NC_Mule, If the gear is worn significantly, It won't mesh well with the other gears, and create a whine, while a worn bearing creates more of a rumble.

[NC_Mule]

NC_Mule, If the gear is worn significantly, It won't mesh well with the other gears, and create a whine, while a worn bearing creates more of a rumble.

O.k cool, thanks for the info. Building knowledge for when I need to tear into my T case/tranny.
pb

[SalemRover]

had some to keep pulling things apart. You called it Terriann. That is one worn bushing. My only concern is that a newer intermediate gear wont mesh correctly with the worn high range gear on the rear output shaft.

8681

[TeriAnn]

had some to keep pulling things apart. You called it Terriann. That is one worn bushing. My only concern is that a newer intermediate gear wont mesh correctly with the worn high range gear on the rear output shaft.

8681

If you want quiet or what passes for quiet in a Series transfercase you need to replace all three gears in the transfercase. Time for a full rebuild with new gears, bearings & bushings.

The other thing that causes a scream under acceleration in a transfercase without an overdrive is if the bearing at the back end of the gearbox output shaft goes bad. Without that bearing the end of the gearbox output shaft bends under power lifting the gearbox output gear (inside the transfercase) up and away from the intermediate gear. This cause rapid uneven wear on the transfercase gears and can destroy the end of the gearbox output shaft requiring a gearbox rebuild as well.

One should never run with low transfercase fluid. Might as well go ahead and pull the plate at the back of the output shaft as well and check the condition of the shaft and bearing. Hopefully it is in good shape.

[SalemRover]

Ill check the rear output bearing. I doubt it has gone bad as the gearbox was recently rebuilt and has not run low to date. I plan on removing the transfercase, and replacing it as I recently picked up a tcase with good internals in a trade. The new thrust washers showed up today from our host. Here is a much better shot of the carnage with a new thrust washer for comparison.

8695

[cedryck]

keeping the gearbox, and tranny case full of 90W is essential to smooth shifting, proper bearing lubrication, and general long life of the gear box. My series 2a often dumps the gearbox into the transfercase, place car on level ground and pull plugs to check level fill from top if low, cheers,

[TeriAnn]

Ill check the rear output bearing. I doubt it has gone bad as the gearbox was recently rebuilt and has not run low to date. I plan on removing the transfercase, and replacing it as I recently picked up a tcase with good internals in a trade. The new thrust washers showed up today from our host. Here is a much better shot of the carnage with a new thrust washer for comparison.

Are you replacing the intermediate gear bearings as well?

[SalemRover]

I am replacing the intermediate bearings. Its nice that they are not expensive. The funny thing is the transferbox had plenty of oil. It did not run low and whine like I assumed. It simply wore out and the intermediate gear was askew under load causing uneven wear to the thrust washer, etc.

[JimCT]

Try running Red Line Shock Pruff gear oil , worked wonders on our '68 ambulance






I am replacing the intermediate bearings. Its nice that they are not expensive. The funny thing is the transferbox had plenty of oil. It did not run low and whine like I assumed. It simply wore out and the intermediate gear was askew under load causing uneven wear to the thrust washer, etc.