Ok so I rebuild my transmission. I just replaced my input shaft bearing and filled it with red line Mt 90. I put all new seals but messed one up in the process and had to drain and replace the seal. Well when I drained the oil I notices it was riddled with tiny metal flakes. It was everywhere suspended in the oil. Tiny metal flake in the oil. I will post pics in a few mi ures.

I read that when you rebuild your transmission it is normal for the transmission to have flakes while it's breaking in. So I'm not sure if it's normal or excessive.

 

any one? i dont want to keep driving the car if its not normal

 

honestly I don't know if its normal, but have you tried googling the subject in general and not specifically a maxima?

 

yea i have been searching and searching. but most is about automatics. i have found some info, i posted that they say some metal is gooing to happen when you rebuild which i guess makes sense. there is no noise i can hear

 

well the only thing I was able to locate was that if your shifting improperly(scraping gears) it could cause that. How many miles have you had on this rebuilt tranny? Is this the first time you have changed the fluid since the rebuild?

 

well its not a full rebuild, i did it my self i i changed just the input shaft bearing, and its been maybe 50 miles since i put the fluid in.

 

Was the tranny completely dry when you you changed the input shaft bearing? I do know a bad input shaft bearing will cause metal flakes so could these metal flakes be from your old/bad input shaft bearing?

Did you put the bearing in with the proper torque specs?

There are several variables here so really if no one replies you can keep searching or keep driving it and change the fluid again and see if the shavings decrease.

 

I took it to a shop and they used a 20 ton press to put them on. I completely cleaned the case so it's not from the old ones. And there's no noise

 

Holy **** that's alot of flakes! I've seen rebuilt trans flakes but nothing like this before!

 

that's excessive. mt-90 is a pretty gold color so it's hard to tell if those flakes themselves are gold or if they are silver and the

if they are gold then it's synchro brass flakes you are seeing, but i bet it's from one or more gears spalling on one or both shafts. seen it a million times with this trans. probably 3/4 of the maxima 5spd's i've been inside have had some level of spalling, but if this is from spalling after only a short time you've got a major amount going on.

regardless, you have a significant issue.

 

But there was no wear on the gears whatsoever when I took it apart. How could this happen right after I changed just those two bearings? Could it be because of this super light gear oil. Compared to the one I removed it was so thick. The shavings also do not appear to be magnetic if that means anything

 

spalling on the inside diameter of the gear where they ride on the shafts. our trans uses a stupid design that has no bearings between the gear and shaft, just some lame oil grooves. unless you totally disassembled the shafts down to their component parts there is no way you could have seen what I'm referring to.

this is just a theory, could be coming from a number of other things too. spalling on cross shaft in the diff from the spider gears, ring gear touching down on the main shaft bottom bearing cage (seen this in most of the maxima transmissions i've been inside too), etc.

 

Well that sucks. I guess I will ride it til it dies, and after a thousand or two miles ill switch to a different oil. Because there's no way for me to disassemble the the entire shafts and by that point I could just buy a used tranny. As of right now the shifting is getting smoother and smoother and there is no noise or vibration at all. It's almost like there is nothing wrong

 

This. If it's brass (looks like it) it's most likely from one or more crapped synchros.

How long did you drive it before draining the oil, and how does the car shift gears?

How did the old gear oil look?

It is odd that if you ONLY did a IPS bearing that you'd 'suddenly' get this, but before I comment on that we need to know how many miles are on that oil, and how the old stuff looked.

Either way, I'm with Neoloc, you have a serious issue here.

 

Not many at all maybe 50. The old oil was super thick and black. Maybe this new oil doesn't lubricate as the old oil. The car shifts much better than before and is getting smoother and smoother. I can even engage first so smoothly going like 10 mph. I its pretty sweet. But not this metal flakes

 

Well if everything is functioning well, it's possible that the old oil was simply way too old, and wasn't picking up the worn pieces. Once you put new oil in, the new oil grabbed all of the worn stuff right away.

I assume you changed the oil AGAIN right? If not, do that. I'd also recommend after the new-new oil change, run it for 100 miles and then re-check the oil again. If you don't have flakes in it after that, then you're probably ok, and the scenario I mentioned above could be true.

if you STILL have flakes in it after the new-new oil is in and run for 100 miles, then you defiantly have some issue there that will only rapidly get worse.

OH, and don't bother with the expensive oil for this test, just put generic gear oil in, not worth throwing any more money away at this point, you're using oil as a diagnostic tool, don't waste the money.

 

Definitely will do that thanks. Could you please tell me where I can find cheap gl4 because dealer stuff is super expensive as well. I also on a side note, all those black spots are old crust from in between the gears and syncros. Witch adds credence to your second theory. As neoloc said the gears don't use bearings its possible the flakes where stuck there with the wasted old oil that probably didn't lubricate properly at all anymore. And that would be much nicer to my pockets lol.

 

just buy any gl4/gl5 from the parts store. gl5 is generally not recommended for our transmission true, but your are not going to hurt anything with it in 100 miles (and gl5 actually has better bearing and gear lubricating properties than GL4 does anyways). the only issue with GL5 is that over long long periods of time it can tarnish synchros some, in the short term it can simply degrade synchro performance because it is too "slippery" for brass/bronze synchros to function optimally.

 

It will feel strange putting gl5 in there. A little nerve wrecking

 

as i said, GL5 is superior in every respect except for shifting action might be degraded a bit. your fears are unfounded. this transmission is taking a ****. i built race and street transmissions for 4.5 years. I know a lot about this stuff.

i would venture that 90% of the maxima 5spds on the road have GL5 oil in them because it is more plentiful and most people don't have a clue that there is a difference, and it works fine. so your synchros might last 70,000 miles instead of 100,000 miles. who cares, this transmission is probably going to eat itself to death in less than ten thousand miles given the amount of metal in your 50 mile oil.

senseless to spend a bunch of money on gear oil that you're going to use for 2 days. GL5 is not acid, it's not going to eat your synchros away like lots of people who don't know anything about transmissions claim.

 

I'd be more comfortable putting hydraulic oil in there than putting the gold flakey stuff back in,

Neoloc knows his stuff. Get whatever is cheaper. I'd try to get GL4 if you can, but wouldn't go nuts looking for it or spend more for it.

 

I guess I will put gl5 since the transmission looks ****ed anyway. It just seems so strange it would happen so fast and suddenly, especially since everything expet that bearing looked damaged or worn at all, the syncros were a little worn but the do have 150,000 miles on them, I'm trying to wrap my head around it and it's too strange, just that bearing got pitted to hell but everything else turned smooth, all the gears on the shaft spun smooth and had no play at all. The differential and main shaft spun freely and didn't even have barely a spall on them after 150k miles. It's BS if you ask me? And the car drives so smooth, I guess it's the calm before the ****storm.

 

it's possible they damaged something while pressing the bearing on.

 

I saw when they put it on with the press it seemed to go in straight and smooth