transmission oil change from 20W to ATF (1.23:1 PCM)

[Daryl]

My 1990 SN has still got straight 20 weight oil in the transmission and i'm considering changing to Dextron III as this is apparently now recommended in the 1.23 PCM tranmissions.

i'm looking for any and all comments regarding this but here is a couple of questions.

is the change over to ATF REALLY recommneded? What are the benefits?
if it ain't broke, should I fix it?
how many changes of the fluid will be required to get all the old oil out?

thanks in advance! happy boating everyone - the season is even here in Canada!

[wakejunky]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

The recommended procedure is to extract the oil out and replace with ATF, run it a bit and extract the ATF/Oil and then replace with ATF again. Reason is to pull out at much of the oil as possible so, as to no have a mix in the case. Luckily it doesn't take much ATF so, it won't break the bank.

Chris

[97SN]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

The service manual on my 1997 SN says the tranny holds 2 quarts of fluid. I used a hand-pump oil extractor and got just over two quarts out, so this appears to be a sufficient, easy way to drain all the oil.

[M3Fan]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

Daryl-

I talked to the ski dim guys about this. Trans fluid is basically lightweight oil packed with detergents and other additives. My 90 has always had 20 wt. There is no advantage to switching that I know of, and the ski dim guys and I agreed that if it ain't broke, don't fix it. If the trans is used to that fluid for 16 years, why fool with it!? My trans has 1100 hours on it, and works like a charm. BTW, if your trans makes a squeaking noise at idle, PM me because PCM has a fix for that.

[Daryl]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

thanks for the responses guys, pretty much what i figured, no real reason to switch....

M3Fan, thanks for the offer but I don't have any squeakys. (I have read some posts about a PCM recall somewhere to relieve some pressure during idle)

so... I'll likely just suck out some 20 and replace with the same stuff.

[SkiNautique2001]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

I changed my 20wt to dextron III this year because straight 20 wt is getting so hard to find. I talked with PCM and 2 CC dealers, and all 3 parties said that neither was "better," but that dealers were changing the fluid to dextron as a standard practice. I changed it 3 times using an oil pump extractor. I ran it each time for about 5 minutes between fluid changes. By the second change, the fluid remained bright red. I also put high mileage tranny fluid in just to keep the seals conditioned as well as possible. Just my 2 cents though.

[M3Fan]

RE: transmission oil change from 20W to ATF (1.23:1 PCM)

I've been able to find it all over (north chicago suburbs) with no problems. Keep in mind it may be labeled 20W-20, which is straight 20.

[EchoLodge]

For those having a hard time finding 20W. I called to confirm it wasn't outdated info on their website!

http://www.doitbest.com/Motor+oils-W...sku-579617.dib

[DanielC]

If you disconnect the oil hose on the top of the 1 to 1.23 transmission, and blow into the hose, it pushes the oil in the hoses and cooler into the sump of the transmission. then suck that oil out too. This leaves less old oil in the transmission, when you need to change it completely.
I have found that sometimes you can get the Dexron/Mercon fluid in gallon containers, and it ends up being much cheaper than buying quarts.

[EchoLodge]

Good to know.... Thanks!

[fcoespinoza@piveg.com]

squeaking noise at idle

Daryl-

I talked to the ski dim guys about this. Trans fluid is basically lightweight oil packed with detergents and other additives. My 90 has always had 20 wt. There is no advantage to switching that I know of, and the ski dim guys and I agreed that if it ain't broke, don't fix it. If the trans is used to that fluid for 16 years, why fool with it!? My trans has 1100 hours on it, and works like a charm. BTW, if your trans makes a squeaking noise at idle, PM me because PCM has a fix for that.

Hello M3, my trans is making that squeaking noise at ide, and it goes away when I shift to gear, and I am afraid it will end up with me at the middle of the lake with nobody to help me. My boat is a super air nautique 230 2008. Tks!