transmission fluid change, now new sound?!?

I recently changed the transmission fluid in my 2000 xstar (preditor engine, combined vdrive/trany).

Now, when I put the boat in neutral after reving it, I hear a faint grinding noise, kinda could sound like the clutch plates rubbing. Usually lasts for 1-2 seconds while the engine revs down.

I used one a tempo pump/container to siphon the fluid out of the dipstick hole. I filled until the dipstick read full, but that was about 1/2 quart less fluid than I siphoned out. I tried adding another 1/2 quart so I would have replaced the same amount of fluid as I took out, and it still does it.

The fluid I removed was dark red, no milkey or white color.

any ideas what this sound is? I already have the typical mastercraft trany rattle, and this is not that sound.

Check your dip stick it could be a little crooked and rubbing on the gears. I checked my oil and it made a funny sound, then I looked at the dip stick and wiggled it around, no more noise. Hope it is that simple.

I am looking at some older v-drives and asked a local MC service manager about the Hurth transmissions. He said the only complaint has been noise, and they replace the transmission fluid with 15W-40 Motor Oil. It solves the problem. There is also info on this over on TMC; apparently it was a service bulletin from Hurth.

I've read that about the 15w-40, but I'd like to read the bulletin myself and make sure I have that exact transmission (did they have different transmissions depending on the 310 vs 330 hp engines?)

I would use the 15-40W Penzoil or whatever you use in your engine itself. The tranny's will be the same regardless of engine model.

I talked to mark at marinegears.com who helped be rebuild the tranny on my old stars adn stripes, and he has never heard of using motor oil in any transmission or vdrive, and said he has never seen a service bulletin of anysort by hurth.

is this the transmisison on that boat?
http://www.simplicity-marine.com/hurth630.htm

My Vdrive specifies that it uses 30 wt motor oil.

The transmission uses ATF. I wouldn't recommend using anything different than what the manual says.

what's the difference between the transmission and the v-drive?

The Walter v-drive consists of a transfer case (that's the v-drive), and then a transmission that sits under it; two separate components each needing fluid. The Hurth is all one unit.

yes, the hurth is one unit.

My mastercraft service manager said that its not hurth that recommends motor oil, but its mastercraft that does, and this is in the hurth 630v transmission/vdrive unit.

supposedly, its the same basic trany that is on an 06 x1 and that will come from mastercraft with a 15w40 sticker on the transmission.

can anyone with an x1 verify?

it could be the flex plate. i would have you dealer check it out.

My 04 X2 came with a sticker on the tranny saying to use 15x40 motor oil. I am also pretty sure the Hurth manual say to use motor oil.

Yes, Use motor oil (15w-40) when replacing the drive oil in your Hurth. The early Hurth installations in MC's had the "chatter" but using this oil will eliminate the problem. The red fluid that came out was Dextron III (Typical DOT ATF fluid). Also, dont forget to change your V-drive fluid every 100 hrs. Indmar is now suggesting that the trans filter on the Hurth V-Drive be changed on this same interval.

It's MC that recommends the 15-W40, ZF Marine/Hurth does not.

I spoke to a local rep a couple of years back. He said that he knew MC was recommending it, but they (ZF Hurth) as the manufacturer did not. My '03 X2 came with the 15W40 sticker, but the ZF manual says tranny oil, which is what I have been running all along, no noise.