Is there any reason by tranny fluid should look like this? I've only had the gear oil in there for less than 10k miles. I had to replace the backup switch due to a leak and this is how my fluid looked.

This is amsoil mtg 75-90 gl4 gear oil.

Because just because you drain the old fluid doesnt mean all of it gets out. But yours is DEFINATLY blacker than usual. Did you try running a magnet through the fluid to check for metal shavings?

I'm positive there are metal shavings because when i look at it in the light its kinda like looking at an metallic paint job. My transmission runs fine though.

Yep, that's bearing material, so fine that it looks black in the oil. Let that stuff sit for a few hours, and try to find the largest flakes when you pour out the old oil. The size of the biggest flakes tend to tell how badly worn your bearings are. I would still try to keep good clean oil in there.

Dave

The problems just never end. How much would it cost to get those bearings you are talking about fixed? I would keep clean oil in there but Amsoil is expensive and i cant find gl4 anywhere. Would i be better off leaving the old amsoil in there or chaning it out with cheaper gl5 oil even though it eats up the metals?

Also i've changed my tranny fluid 2 x's since i bought the car and it was black like that. When i drained it the first time the oil was nice and yellow. That was at 96k. I'm now sitting at 122k.

Doesn't look good. I would atleast keep a close eye on that. Do fluid checks at closer intevals.

You should be able to find a GL4/GL5 oil instead of a regular GL5. If this stuff only has 10k I have to be honest I don't think new clean oil will make that much difference. New oil will get just about as dirty right away.

In any case, yep you'll need to put at least $500 into a rebuild, and that doesn't include removal/install. Add $200 if you expect new synchros, but those usually aren't necessary unless you've bashed them already.

Dave

This car is costing me a grip. So do these bearings just go bad eventually are do they go bad because of neglect/abuse? I drive this car like a grandpa.

I wouldn't just jump to the conclusion that the input shaft bearings are bad.

Probably not input shaft bearings - they tend to make noise when they're failing.

I would bet it's the diff carrier bearings, which spall slowly at first and fill the oil with tiny flecks. The flecks get bigger as they wear further, and the wear accelerates.

IMHO, there is something about the design such that the diff carrier bearings often fail between 100k-200k. The good news is that if the tranny is rebuilt with new bearings, they will probably last just as long as the first set. Just a thing that happens to some Maxima 5 speeds.

Dave

So what are other signs that my tranny/bearings is going down the hole? The car runs strong and fine and the transmission feels normal. I just want to get this solved so i dont get stranded.

I ment diff bearings (did my input shaft bearing a while back, don't know why I said that. Must have been on my mind)

My point was that I would not jump to conclusions that it was the diff bearings. Yes, they are a common problem on 5spd 95-01 maxima's (mine went bad at 100K) but I would look for other signs before replacing. leaking fluid at the axel seal? High pitched noice in 2nd gear?

Of all of the trannys I've opened that have that black flecky oil have, the diff carrier bearings were always the worst worn and usually completely or nearly shot.

I'm not giving a formal diagnosis, but they are the most probable source of all those suspended solids. In any case, I wouldn't go into a tranny with oil like that without at least a full bearing kit on hand. The full set of bearings isn't very expensive to change once it's off the car.

i just drained my tranny of the redline in it and it looked the same as the day i put it in, so you definitely have a situation brewing in your trans...