BCS Transmission

[Devon]

What fluid is recommended for the BCS transmission? Mine is overdue for a change & I didn't get an owners manual when I bought it.

Also, how do you drain the old fluid?

Thanks!!

 

[mn_voyageur]

Which tractor do you have?

Mark

 

[Devon]

It is a 730.

Sorry, I figured that they were all the same.

 

[farmerboybill]

Hey Devon,

Do you have a manual? If you don't, you can buy a CD from John at the BCS Shop in Massachusetts. His CD has all the manuals, parts breakdowns, and service manuals. AND it's only $10! It also has some other interesting info and movies, but the true value are the manuals.

Page 25 in the manual states that you should use SAE 80/90 or SAE 90 EP. Joel at Earth Tools told me awhile back that he doesn't recmmend EP oils. A straight 90 will do just fine in southern climates and summer-only use. An 80/90 is good for northern climates if you use the 730 in the winter.

There's a plug on the bottom of the transmission to drain the oil, and a dipstick on a plastic breather at the top to fill it.

 

[mn_voyageur]

Bill,

I googled, "EP oil". The hit said it was "extreme pressure."

Is this typically mentioned on the bottle?

Also, is the CD from BCS?

Devon - I was more concerned about the location of the drain plug. Since I only have used the 853, i was going to look at the IPB. (Illustrated Parts Breakdown)

Mark

 

[Devon]

Thanks so much for the info. I'll get the transmission fluid changed before spring. I've had it for several years & it has been a workhorse. Sure fluffs up the dirt nicely. We put in a huge garden. I've been diligent in maintaining the Kohler engine, but have neglected the transmission.

 

[farmerboybill]

Hey Mark,

I just don't look for EP oil even though the manual requires it. I may very well be buying EP oil, but I'm not looking for it.

The CD John sells is the one BCS gives to the dealers.

Bill

 

[pangavamanos]

Devon,

Look at your auto parts store for "rear end oil". It is EP gear oil.

 

[mainerr]

I've been doing lots of reading on this. Primarily in regards to the sulfur issue.

First, the Earth Tools website has this document: http://www.earthtoolsbcs.com/pdf/Proper_Lubrication_of_Walk_Behind_Tractors.pdf

Which states:

There are many different weights of Gear oil: 75w90, 80w90, 85w140, etc. etc. The weight
is actually not so important (any of the weights mentioned will work)…what IS important is
whether the oil is approved for use WITH BRONZE GEARS (also called Yellow Metal gears). This
is because the final wheel drive gear (on the axle itself) in all walk-behind tractors is a
bronze worm gear. Most gear oils these days are safe for bronze/yellow metal gears, but a few
gear oils still contain sulfur, which can damage yellow metals such as bronze. So, whether
purchasing a synthetic or non-synthetic gear oil for your tractor, check the oil
specifications to make sure it is safe for “yellow metal” gears. BCS and Grillo
recommend an 80W90, GL-5 (EP) gear oil. Synthetic oils usually cover a broader weight-range
(such as 75W90 or 75W140), which is fine, and the synthetic oils will last longer, provide
better high-temperature protection, as well as having the benefit of not thickening up as
much in cold weather

Next, here's a writeup on GL4 vs GL5: http://www.widman.biz/uploads/Transaxle_oil.pdf

Which states:

Eventually it was discovered that the active sulfur was causing corrosion of brass and other soft metals
used in differentials and transmissions.
Somewhere around 25 years ago a deactivated or buffered sulfur was developed that would react with
the phosphorous to create the protective/sacrificial layer in the conditions created in the gear boxes
(temperature and pressure) without being corrosive to the brass, copper, etc. This additive system is
used in most gear oils today.

Here's a simpler GL4 vs GL5 writeup: What is the difference between GL-4 and GL-5 gear oils? | Reference.com


Here's another twist: http://www.tractorbynet.com/forums/chinese-tractors/199042-fyi-coastal-gear-oil-gl.html

it's not the sulfur that makes some oils corrosive, it's the form of the sulfur, and Coastal uses sulfur compounds that don't react with yellow metals. According to him, the additive package in GL-5 is the same as the other GL ratings (GL-4, etc.), it's just that there is more of it.

Finally, I asked BCS customer service, this was their response:

Any synthetic oil will be fine, as long as the oil is classified as a synthetic 80/90W. Most of the oil brands are very similar and we don't have a specific recommendation.

I want to do this once and I want it to be correct. Does anyone have a specific oil they can recommend that is synthetic and safe for a BCS?

 

[mainerr]

Here is one I found:

Amazon.com: Royal Purple Max Gear 75W-9 High Performance Synthetic Automotive Gear Oil - 1 qt.: Automotive

Max Gear is recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid. It is non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe.

I think some of my local stores will carry it.