Transmission fluid change

[nazinteck]

I have Series 5000 Borg Warner Velvet Drive transmissions on my two 350 Crusader engines on a 1997 325 Carver Aft Cabin. I am still in the process of going through the vessel which I purchased in May 18 and my plan is to refresh all the mechanicals for piece of mind and reliability. My transmission manual calls for 2 quarts of DEXRON II E for each transmission. A quick inquiry identifies that DEXRON II E is no longer manufactured. Some say DEXRON III is an equivalent replacement fluid. Has anyone substituted the fluid or have any other options. I also see some articles say DEXRON VI is also a replacement for the original recommendation too? Does anyone prefer a specific manufacturer of DEXRON? Any help is appreciated. This is strictly a maintenance issue as I have no transmission issues.

[km1125]

I don't think you'd have any problem with III. The newest (I think VI?) has a much lower viscosity intended for newer high-mileage transmissions. I have heard of a LOT of concerns using it in older vintage equipment. It is technically compatible, but with the low viscosity it won't build pressure like II, III or IV. It's been a bit since I did any research, so I would poke around some before I used VI

[bud37]

I have never worried too much about trans fluid, ATF is ATF in my opinion, more of a bother would be the appearance of the fluid you now have in there, is it clear pink with no smell, discoloured and burnt etc.

If you want to err on the side of safety , e mail Borg warner with yours trans type, year and serial number and ask them what fluid to use and the fluid change procedure if any.

[nazinteck]

Thanks to you both. I tried to contact BW but opted to contact a local BW distributor in Rochester NY instead as it was much simpler that way. I spoke with the customer service person there and he followed along with my transmission description, etc. He recommended that I use DEXRON II E or DEXRON III. He had 14 quarts of the "old stuff" II E in stock and will UPS it to me at $3.75 a quart overnight. It is good to know the distributors have inside Customer Service people who can help out. He said a 10 year fluid change is recommended due to possible condensation issues inside the transmission over a period of years. Other than that, there is usually no problem with the fluid. Mine was deep pink with no burnt smell, but since I have no references to any transmission fluid change in the past I am being cautious.

[RGrew176]

Some good information you shared. I appreciate that you found out about the 10 year fluid change. I changed mine last year so I have somewhat over 8 years to go before another change.

[Viper]

The caution here is that you not relax your maintenance concerns for the transmissions for 10 years after an oil change. You must still check your oil levels and condition on a regular basis. Personally, 10 years is too long. There's no way I'd run anything with oil that's more than 2 years old IMO. I replace engine oil every year.

[nazinteck]

I like to heed good advice and Viper's comments made me look into some of the recommendations I received. I have a Borg-Warner Velvet Drive Series 5000 marine transmission attached to my Crusader 350 5.7l TBI engines. Approved transmission fluid is typically DEXRON II E or DEXRON III. I used DEXRON III due to ease of availability. According to the manufacturers Marine Service Manual which I found on-line, other APPROVED fluids are Ford Mercon, Detroit Diesel Allison C4, Caterpillar TO-4 and Daimler-Benz 236.6. The Service Manual states that the fluid should be checked weekly. It also states that SEASONAL transmission oil changes are REQUIRED for all pleasure boats. Work boats require transmission fluid change every 1000 hours. Obviously the pleasure boat and the work boats time intervals are not to be confused and recreational boaters should follow the annual requirement. Thanks Viper for making me look a little deeper into the question. I'm good to go for another year.

[km1125]

I cannot imagine having the change out the transmission fluid every year. That seems pretty excessive to me. Engine oil makes a lot of sense, because it is constantly getting bombarded with combustion products and the high under-piston temperatures. You also get moisture from those combustion products.

Other than the vent, the transmissions and gears are pretty much sealed up.

[Midnightsun]

Source of the post I cannot imagine having the change out the transmission fluid every year. That seems pretty excessive to me. Engine oil makes a lot of sense, because it is constantly getting bombarded with combustion products and the high under-piston temperatures. You also get moisture from those combustion products.

Other than the vent, the transmissions and gears are pretty much sealed up.

I am thinking the same. I do know my Volvo transmissions are supposed to be changed every year or 200 hrs which is rather too often if you ask me. They also say to change the filter however the filter is a medium washable stainless steel wire mesh! These are washable and not supposed to be changed, just cleaned. Regardless, when I did do the change the oil was like new and the filter also. Oil even smelled like new. I am pretty sure it was 10 year old oil and the original filter. I will probably be changing every couple or 3 years from now on.

[RGrew176]

Thinking more about this I think 10 years is to long. I guess depending on how many hours you put on in a season would have a large determination as to how often to change the fluid. I put 54 hours on last year and only a couple so far this season. I am leaning towards every 5 years. My thoughts could change as other information is known.