Where does the transmission fluid disappear?

[Ricardo Cotte]

I have had issues before with my 310SJ parking brake delayed release and also not moving in gear. Many folks here, especially mg2361 have helped me with great advice.

I have been able to fix this by changing oil and filter and most importantly topping off the reservoir a tad over the dipstick mark.

Now, this issue is coming back and as advised before, first thing I check is the fluid level.

Well, again is below the arrows on the dipstick.

I don't see any leaks anywhere which makes me wonder where could this fluid may be escaping or disappearing. This is not an overworked machine and it is used sparingly.

I know engines "burning" oil (yes, I do have a Subaru EJ25 and have had experience with similar aircraft engines disappearing oil due to blow by). But this is a transmission. How could it be managing to disappear oil?

The worst about this it is very difficult for me to get the JD stuff locally (also super expensive).

I have thought on replacing the oil but I don't think I may be able to flush it completely so I can change brands. The torque converter will always keep a good amount. Maybe change it twice? Three times?

 

[HardRockNM]

It has to be going somewhere. Have you checked other systems for overfilling, that would indicate bad seals allowing transmission oil to transfer?

 

[Bote]

On my 580M one of the brakes leaks by a little which causes THF to build up in the differential. I check the level and drain the excess every 20 hours or so. The THF from the brakes on the 580M comes from the main tank, not the transmission. On the JD, is the THF for the transmission connected to anything else?

 

[Diesel Dave]

I have had issues before with my 310SJ parking brake delayed release and also not moving in gear. Many folks here, especially mg2361 have helped me with great advice.

I have been able to fix this by changing oil and filter and most importantly topping off the reservoir a tad over the dipstick mark.

Now, this issue is coming back and as advised before, first thing I check is the fluid level.

Well, again is below the arrows on the dipstick.

I don't see any leaks anywhere which makes me wonder where could this fluid may be escaping or disappearing. This is not an overworked machine and it is used sparingly.

I know engines "burning" oil (yes, I do have a Subaru EJ25 and have had experience with similar aircraft engines disappearing oil due to blow by). But this is a transmission. How could it be managing to disappear oil?

The worst about this it is very difficult for me to get the JD stuff locally (also super expensive).

I have thought on replacing the oil but I don't think I may be able to flush it completely so I can change brands. The torque converter will always keep a good amount. Maybe change it twice? Three times?

Ricardo, I suspect the rear axle overtime is slowly overfilling with transmission fluid. Remove the rear axle oil fill/ level plug to verify.
The sources of a transmission fluid leak into the rear axle are the park brake piston seals and or the differential lock piston seals.
The only seals you can change without removing the rear axle is the park brake piston seals. I might start with resealing that first.

 

[Ricardo Cotte]

It has to be going somewhere. Have you checked other systems for overfilling, that would indicate bad seals allowing transmission oil to transfer?

Hello HardRockMN,

Nope, I had not thought about that possibility which makes perfect sense. Thanks for your suggesttion.

 

[Ricardo Cotte]

Hello Bote and thanks much for your reply. On my John Deere the transmission is a world separate from the hydraulic system except that the pump is driven mechanically by PTO directly on the tranny.

On my 580M one of the brakes leaks by a little which causes THF to build up in the differential. I check the level and drain the excess every 20 hours or so. The THF from the brakes on the 580M comes from the main tank, not the transmission. On the JD, is the THF for the transmission connected to anything else?

 

[Ricardo Cotte]

Hello Diesel Dave,

Thank you so much for your diagnostic. It makes a lot of sense just like the other posts by Hard Rock and Bote.

I am aware of your knowledge of these machines and appreciate letting me know about this possibility with the 310SJ. The parking brake is operated with pressure from the ZF transmission oil pump. If it gets low it starts acting up. And it will fail if there's not enough oil level for suction.

I hope those piston seals are not too difficult to change. Is this something a newbie like me be able to pull off?

You mentioned the diff lock seals being another thing. Hopefully that is not the case. I have never used that feature on my backhoe and it would be ironic having to repair something not used or needed at all.

I will report back as soon as I am able to check the oil level on the rear axle. Thanks again!

 

[mg2361]

The 310SJ's had an issue with the park brake piston bore being machined too rough, prematurely wearing out the park brake seals. Make sure to polish the bore thoroughly with emery paper or something similar before assembling back together.

According to your serial number, you have an axle that falls into the range of the machining issue.

 

[Ricardo Cotte]

OMG! I don't have words to express my gratitude and respect for the knowledge gained from good people here at HEF. You guys are really awesome and speaks to the vast amount of work performed under your belt.

Thanks much again for your kind help mg2361. I certainly couldn't get this type of information from the repair manuals.

 

[Ricardo Cotte]

First, sorry about not updating before. It was only today I was able to check on the rear axle oil level.

Exactly as advised by Diesel Dave and mg2361...rear axle not only overfilled but overflowed for a good five minutes until I had to put the Plug back on because my drain pan was about to overflow. (See photo)

Where do I go now from here now that I know where the transmission fluid was "disappearing"?

How bad would be to just add additional oil and drain the rear axle again until I get set to repair the park brake assembly? Getting parts and preparing for either do it myself or get a mechanic that has done this before?

Is it worth venturing in doing it myself ? The local JD dealer mentioned they sell these kit regularly meaning it is one of those "lemon" issues.

 

[Ricardo Cotte]

See video of outflow from oil level hole...

 

[Diesel Dave]

I see no problem to continue draining the axle and topping off the transmission while you get organized.
I will send you some repair info which may help you decide if you want to tackle the park brake re-seal yourself.

 

[Ricardo Cotte]

Hello Diesel Dave,

Thanks for your input. I drained a good 5 gals excess from the rear axle. I'm dumfounded about how the axle housing was able to accumulate that additional amount without symptoms other than the constant replenish to the transmission.

I figured that, yes, it would be a matter adding oil and draining regularly. As long as it doesn't cause a major problem it would just be a bearable money pit buying oil. Thanks for your opinion.

I will appreciate you sending information on the undertaking to repair the parking brake. The JD repair manual I have is not specific on repair procedures but I am willing to learn. At least it looks like the axle doesn't have to be removed.

 

[cosmaar1]

Hello Diesel Dave,

Thanks for your input. I drained a good 5 gals excess from the rear axle. I'm dumfounded about how the axle housing was able to accumulate that additional amount without symptoms other than the constant replenish to the transmission.

I figured that, yes, it would be a matter adding oil and draining regularly. As long as it doesn't cause a major problem it would just be a bearable money pit buying oil. Thanks for your opinion.

I will appreciate you sending information on the undertaking to repair the parking brake. The JD repair manual I have is not specific on repair procedures but I am willing to learn. At least it looks like the axle doesn't have to be removed.

Look at it this way…. It will keep the fluid fresh and keep the rear end clean!

In all seriousness, good luck on the repairs!

 

[Ricardo Cotte]

Yeah I will be recirculating fairly good oil all along! Until the parking brake no longer holds.

I'm planning on getting the parts and staging an area where I will attempt the repair.