metal on transmission drain plug

[5bzhive]

Hey all.

I went to change the trans oil last night (5 speed from an zx) and it had quite a bit of metal on the magnetic plug. How much you ask? well if I spread it out it might be the size of a quarter round and thick. It is all fine metal but still I am wondering if this is a problem. I have no idea when the last time the trans oil was changed. I want to flush with say a quart of gas then after a nights wait refill it. Might do it again after a couple hundred of miles just to see the new amount.

Any thoughts?

[Zed Head]

Have you ever changed the fluid before or is it possible that it's the original fluid?

If all of the pieces are fine, there's not a lot you can do or worry about. The bearings are all designed with a loose fit to flush debris through and the magnet will grab whatever passes by as the oil circulates. Flushing with gas won't do much but put more wear on the bearings and synchros, maybe even cause a failure that wouldn't have otherwise happened. A fine paste of metal shavings is normal for an old transmission.

I would just put the new fluid in and drive it. If you're worried, drive it for a few hundred miles, drain the fluid in to a clean container, examine the magnet, then put the fluid back in. You'll probably find no new shavings.

[5bzhive]

I don't believe it is the original oil.

I was going to put a magnet into the oil to see if there was any in suspension in the oil. I would be amazed if the magnet catches all the metal in the oil. That is why I was thing of pouring some gas into the trans to flush out any metal on the bottom through the drain hole. I wouldn't drive with the gas in there just use it as a medium to carry any other metal out. I have seen some metal in other transmission oil but I don't remember it being this much.

Here is a pic of the metal.

Thanks for the reply.

[72 OJ]

Zed Head,,,has some very valid points

[Kurbycar32]

I also concur..

But it sounds like your going to flush it anyway, dont use gasoline. If you insist on flushing, ATF has always been my go to flushing fluid. Its a lubricant unlike gasoline, contains detergents in some cases and is sometimes found in manual transmissions anyway. If forced to flush: I would fill with ATF, drive around the block and then replace with whatever oil your repair manual specifies.

You would probably get a similar, less scary result by refilling with a synthetic fluid. If your still worried put some high power magnets on the outside of the casing near the drain plug

[tlorber]

I concur with Kurbycar (say that 3 times fast). The ATF is thin enough to flush and shoudn't damage seals like gasonline probably will.

The plug/magnet are at the lowest point in the tranny, so theoretically, any metal filings (which are more dense than the oil) will sink to the bottom and get stuck to the magnet.

Problems arise when you start seeing larger portions of the bearing races broken off and residing on the plug.

[5bzhive]

Point taken.

I will refill (minus the flush) and check it again in 2 to 3 hundred miles to see how it looks.

To go to synthetic fluid wouldn't I have to get all the old dino oil out first somehow or is just draining it out ok?

Thanks for info guys.

[Kurbycar32]

To go to synthetic fluid wouldn't I have to get all the old dino oil out first somehow or is just draining it out ok?

Thanks for info guys.

Nah its all compatible. Drain, maybe shake it around a bit and refill with oil of choice.

[tlorber]

Just a note on synthetic, after replacing the conventional 90 wt oil in my roadster tranny with MTL (which I did due to a bad synchro) I get seepage past some of the seals. Shifting is much smoother though.