MT240HE differential oil level

[frcnLS]

Have had a problem with the front differential of my MT240HE spewing oil out of the vent cap on the right side. The manual says to check the oil level so that it is between the min and max markings on the dipstick.. Well, sure- I might be ugly, but I'm not stupid.. But is that checked with the dipstick screwed in or sitting offset on the top edge of the opening? Has anyone used the dipstick on both sides? Is that not done? Would it give a false reading? I ask because left compared to right, mine are very different. This model has no center drain plug- just one on each end. The left side (with the dipstick) is well up on the dipstick while the right side shows quite low. I even used a long bubble level to be sure I was on level ground out of paranoia.

 

[garry1p]

I haven't had the spewing problem but I did read where some were shipped with low differential oil.
I have no dipstick on either side I was wondering how are you supposed to check?
Both sides seem to have the same amount so I didn't add any I have over 200hrs and no problems.

 

[GS650GL]

Check it with the dipstick screwed in. Book does not tell you that. Not necessary to put the dipstick in both sides as the oil will seek its own level in the axle housing once the lower gear cases and king pin cases are filled. Just need to be on level ground, but because the oil is thick it might take some time for it to level out after the tractor is parked. They sometimes shipped to the dealer with low axle oil as garry1p stated in previous post. Possible the dealer overfilled it during predelivery. The vent plug has a baffle in it to help prevent oil coming out, but it could still come out if it was overfilled or something wrong with the vent. I've seen the center cap in the vent broken out. Capacity is 1.7 gallons 80w90 gear oil, and if changing the oil, it takes a couple hours for that thick oil to fill the lower cases and for all the air to come out. Then it needs to be rechecked and topped off. Some people think you check it at the vent plug and don't realize there's a dipstick on the other side. I even saw someone working at a dealership do that because the picture in the book looks like the vent plug where it shows to check it. Have never seen one without a dipstick on either side. Normally a blue vent plug on one side and dipstick and fill plug painted white on other side.

 

[Bearsixty7]

I haven't had the spewing problem but I did read where some were shipped with low differential oil.
I have no dipstick on either side I was wondering how are you supposed to check?
Both sides seem to have the same amount so I didn't add any I have over 200hrs and no problems.

The Metal nut on the driver side (Painted white with yellow mark in pic below) should have a dipstick under it/attached to it. Could it have broken off? That would concern me.

 

[GS650GL]

Good pictures, thanks for posting!

 

[garry1p]

I checked and I have the white and blue but did not take the white one out 99 deg at the time so I will check for the dip stick tomorrow.
I just remember wondering how to check without the dip stick and thought about calling the dealer. I will know tomorrow and post back.

 

[garry1p]

I checked and I do have the dip stick, now I'm wondering what was I doing at that time that made me think I missed the dip stick!

 

[frcnLS]

Not wanting to leave anyone hanging.. I took the advice of:
1 - Check only the left side
2 - Check with the dipstick screwed in
Based on that, the level was high. I removed enough oil to get the level to show about 3/4 full when the dipstick was screwed fully in. Additionally, I checked with the dipstick sitting offset (so only the 'stick' portion was through the hole and the entire nut was sitting on the housing) and it showed just a bit less than 1/4 full. I did that for future reference.

I had previously disassembled a vent plug (the blue plastic plug on the right side), and inside of that is just a flat rubber disk which operates as a one-way valve- allows air (and fluid, obviously) to escape, but seals well enough to hopefully not allow anything in (like water). This function presumably prevents seal failure from pressure caused by the oil and air heating and expanding in the differential. Just take care when pressure washing that area.

I have not yet run the tractor after correcting the level to verify, but it seems that the problem was that I had overfilled the differential at some point. While overfilling creates a horrid mess on the right-side front rim and tire, that is easier to deal with than blown seals.

Finally, the owner's manual certainly could be far more clear on a number of points, of which this is one. I have created a few owner's manuals and guides (not tractor related), including text, photos, and layout. It is quite an undertaking to do so. I have worked on my own vehicles since 1968. I am also a retired teacher. I know how to create step-by-step instructions and procedures and put them to print. When I come across such a blatant omission such as this it really bothers me.

I will keep this topic bookmarked and after running my LS for a while will report back as to whether it pukes or is pukeless.

 

[frcnLS]

Check it with the dipstick screwed in. Book does not tell you that. Not necessary to put the dipstick in both sides as the oil will seek its own level in the axle housing once the lower gear cases and king pin cases are filled. Just need to be on level ground...

This advice was dead on, and thank you!!!

I used a disposable, one-use syringe with a rubber hose attached to lower the oil level, about 20cc at a time. Took the LS out this morning and worked some of my hilly property, widening one trail and created the graded foundation of another. Not a drop leaked!
Because of my lack of understanding I had overfilled the differential quite some time ago. The odd thing was that it would spew a bit of oil now and again and make a bit of a mess, but the last time it was A LOT! I think that science quantifies the amount of excess oil I needed to remove with the syringe as 'embarrassingly ridiculous.' I believe that once the oil reaches the "full' mark on the dipstick, past that point the the rise of the indicated level on the stick is not proportionate to the volume of oil. That is to say, a little over the full mark seems to be a LOT of excessive oil. Looking back, I am glad that there is a vent to allow release of pressure (and excess oil!).

In Summary, and based on my experience with my MT240HE:
1 - Check the oil level only on the left side is sufficient
2 - Check with the dipstick screwed in then removed
3 - Check on level ground
4 - After adding oil wait a good amount of time for the oil to level out
3/4 full when the dipstick is screwed fully in is indicated as APPROXIMATELY 1/4 full with the the dipstick sitting offset so only the 'stick' portion is through the hole and the entire nut is sitting on the housing. This is a handy way to approximate the level when changing the oil or topping off. But always check with the dipstick screwed in for accuracy.