Severe trans or tcase whine

[DannyB1970]

My truck is a 300 6, granny 4 speed 4x4. I never ran it at high speeds but I now have to run at 55 or higher in new town since Ive moved. The truck is fine until it gets warmed up, then something under the seat starts whining like its in granny gear. Every so often something will pop and make a zinging sound then back to whining. It doesn't affect the truck moving when it pops. I can go side to side, put the brakes on, or put it in neutral and coast with the clutch in or out and it will not stop til I stop. It goes with the speed of the truck, its not the motor. Checked wheel bearings, brakes, rebuilt rear-end and all U-joints. Once the truck cools its back to quiet.

[DannyB1970]

The truck has made a rattling sound with the clutch out driving for years. Maybe its got worse inside the trans. I engaged the TC and it made no difference but sometimes the whine sounds like I'm trying to put it in 4x4 at 55 mph. Makes me nervous. Any info would be appreciated. I know nothing about trannys and the mechanic that rode with me doesn't seem to know either, he just wants to replace things til its fixed, which I can't afford. Oh the truck has over 253000 miles on stock drive train.

[BobbyFord]

Not to be sarcastic, but have you checked fluid levels in the diffs, trans and t-case?
Drain the fluid out of the trans and the t-case, in separate, clean drain pans and see which fluid is metallic.

[DannyB1970]

All the fluids are full but I did notice the trans looks like it's getting ATF in it, which should be in my TC only. And the TC looks like it's mixing with gear oil from the trans. I drained the fluid out of the trans and filled it back up with 80w90 but it still made the noise when it got warm and when I got back it was red again like ATF. There was a little metal came out but nothing major, especially since I got the truck in '93 and I never changed it. Just topped it off as needed. It's just weird that I can drive all day at 35 or 40 and never hear a thing but just a few minutes at 55 and it sounds like its going to explode.

[BobbyFord]

Well, if the fluids are mixing, then it's time to pull the t-case. Each is sealed, so it's a little bizarre that they're swapping fluids.

[eggman918]

If the fluids are mixing then the seal between the two is most likely shot,could be from age but it could also be a sign that either the trans output shaft or T case input shaft bearing is going out allowing the shaft to move around too much If it were me once I had it out and apart far enough to inspect I would overhaul both kits aren't too costly and they are fairly simple to do,do it now and they will out live you

[DannyB1970]

Sounds like a major undertaking. I'm A little weary of doing it this close to winter since it's my only 4x4 but I don't want something to break when its 10degrees and 8 inches of snow on the ground. I wonder if I could fill the TC up with gear oil too. That art to quieten it down if its making the noise. Do I have to take everything apart to press those bearings of the shafts or do they go in like rear wheel bearings.

[eggman918]

I ran 75W-90 in my high mile Dana 24 for 20+ years with good results and am running synthetic 75-90 in my newly rebuilt 203/205 so if I were in your shoes i would.I would be planning an overhaul when time,weather and your schedule allow both your trans and T case are pretty tough and "should" get you through the winter but don't take them for granted or Murphy will bite you on the @$$.
Good luck,
Steve.

[1972hiboy]

did I miss something? Its possible but I didnt see what kind of truck this is? f100 f250? if its a f250 then I dont see how it can be swapping fluids? can somebody clarify?

[DannyB1970]

The truck is a 1983 F150. My 1970 F100 is not close to being a daily driver. I know it's not true to the site but most people I know only drive Fords of any kind. Didn't know where else to turn figured some of you had experience with these trucks also. I'd rather walk 10 miles in the snow and hear a good Ford go by as to ride in a Chevy. I did notice today when the noise came back my speedo started jumping around so now I'm really confused.