Part Time Kit Install - Gear Whine

[kazanski]

1997, FF/RR, 150,000 miles. Rebuilt Front/Rear diffs and TC in the past 1000 miles, standard gearing just bearings and seals.

Recently rebuilt Front and Rear diffs along with a complete rebuild of the TC with a Part Time kit with manual hubs. Drove the LC after each sequential rebuild to ensure there weren't any issues before moving on to the next. I was trying to track down the dreaded grinding noise on deceleration, for me it ended up being the input bearing on the front nose of the TC (your mileage may vary there). Anyway, just took the first real highway trip 6 hours to give it a shakedown with everything complete and noticed that a gear whine from TC (I think) seemed much louder than I remember - especially in the 70-80mph range. I have read some random anecdotal comments here about this, but nothing that gives me comfort that this is a normal thing. Anyway, figured I would ask here if this is normal or something I need to be concerned with (I really don't want to have to pull the case again). I have read moving to a higher weight gear oil may help, for now I use 80w-90 Lucas. I plan to sound deaden when I get around to refreshing the interior if this is just normal and I am being overly sensitive...

 

[JoeCova]

1997, FF/RR, 150,000 miles. Rebuilt Front/Rear diffs and TC in the past 1000 miles, standard gearing just bearings and seals.

Recently rebuilt Front and Rear diffs along with a complete rebuild of the TC with a Part Time kit with manual hubs. Drove the LC after each sequential rebuild to ensure there weren't any issues before moving on to the next. I was trying to track down the dreaded grinding noise on deceleration, for me it ended up being the input bearing on the front nose of the TC (your mileage may vary there). Anyway, just took the first real highway trip 6 hours to give it a shakedown with everything complete and noticed that a gear whine from TC (I think) seemed much louder than I remember - especially in the 70-80mph range. I have read some random anecdotal comments here about this, but nothing that gives me comfort that this is a normal thing. Anyway, figured I would ask here if this is normal or something I need to be concerned with (I really don't want to have to pull the case again). I have read moving to a higher weight gear oil may help, for now I use 80w-90 Lucas. I plan to sound deaden when I get around to refreshing the interior if this is just normal and I am being overly sensitive...

People perceive gear whine differently so a video may help us a bit. I regeared my TC and diffs and do not have gear whine at all. 85-140 in the diffs and the TC has normal factory spec.

 

[kazanski]

People perceive gear whine differently so a video may help us a bit. I regeared my TC and diffs and do not have gear whine at all. 85-140 in the diffs and the TC has normal factory spec.

Thanks for the response Joe. Yeah, I will see if I can get a video of it for reference but might be one of those things that is hard to discern without being in the car. Was just thinking since the spool is new and the VC is removed if that creates a circumstance where a whine might be present. Going to do a drain of the oil and move to 85-140 to see if there is anything in oil and test if that reduces the sound. It is really just in the 70-80mph range that it is apparent so it isn't constant, which sucks because that seems to be where it is most comfortable to drive on the highway.

 

[CharlieS]

I can say VC in or out doesn't make a difference in sound/noise on the two I've removed.

 

[Delta VS]

No under/over drive gears installed in t-case, just the spool?

 

[kazanski]

No under/over drive gears installed in t-case, just the spool?

Yes, kept everything else stock, replaced all bearings/seals in the rest of tcase.

 

[Delta VS]

Yes, kept everything else stock, replaced all bearings/seals in the rest of tcase.

have heard plenty of people whining about the aftermarket gears whining, due to less than perfect gear mesh. have not heard of new bearings causing a whine. maybe @cruiseroutfit has some input? they deal with t-cases on a regular basis.

 

[kazanski]

Well, I drained the TC fluid yesterday to replace with the 85-140 and had a nice shimmer to it along with quite a bit of shavings on the drain plug

So either I put something back together wrong, or something found its way in while I was putting it back together... I am starting to stress if the shim came lose while I was putting the case halves back together or something. So it looks like I get to pull the TC again and take a look at what's going on. May try taking the rear off and see what's going on there before I pull the whole thing. I am a glutton for punishment. Not sure what it could be since I have taken it for 3-4 longer trips so far and the only symptom is the whining I am getting in the 70-80mph range (or it looks like around the 3000rpm+).

Just to clarify with the part time kit - what is the "max speed" while it is locked into 4x4? I took it out yesterday after the fluid change, locked it in with no issues to test it out around the block a few times, then switched out and took it for a higher speed in 2wd. Is there a possibility of tearing anything up in 4x4 over a certain speed/terrain?

 

[dallen341]

I get the same whine right at 70mph. I will eventually pull the rear housing and double check bearing preload.