5055E Brakes diminish the longer it runs - HELP

[jsjsteven]

I bought a 2011 5055E about a year ago. It has 1200 hours, 4x4, FEL, AG tires. I have put about 150 hours on it in the last year. Recently the brakes have started giving a problem. When I use it at higher RMP's (2000) to bush hog or plow the longer I run it the more I have to pump the brakes to get a pedal. When I start out the brakes are fine but after about 45 minutes of operation the pedal starts to weaken... meaning I have to press it half way down to get a pedal. the longer I run it the worse it gets to the point of having no pedal and having to pump 8-10 times to get a pedal. Almost instantly after pumping to get a pedal then releasing for a few seconds the pedal is gone again.

I have changed the fluid and filter about 100 hours ago as well as removed and cleaned the suction strainer... it wasn't really dirty though. Fluid level is good. The problem started about 20 hours ago so it wasn't (or didn't seem to be) a direct result of changing the fluid and filter. I have searched and read a lot of things concerning brakes on these tractors but none seem to have the same symptoms that I have.

What is wrong with my tractor? Please help.

 

[Tx Jim]

As you operate tractor is hyd oil temp getting a lot higher(200°+)? Have you bleed brake system? Will brakes operate any better if both pedals are depressed simultaneously?

 

[jsjsteven]

As you operate tractor is hyd oil temp getting a lot higher(200ｰ+)? Have you bleed brake system? Will brakes operate any better if both pedals are depressed simultaneously?

I haven't checked the temp of the fluid. Plan to bleed brakes. The brakes pump up to a firm pedal faster if I pump both pedals... as I would expect.

I would like to see a fluid schematic if anyone has one. I would like to try to understand how fluid is delivered to the brake system.

 

[country101]

Did it do it prior to the fluid change? What fluid did you use? I considered using a cheaper fluid, but after realizing what all it operated and finding out that there are no standards on hydraulic fluid, I wanted to make sure it met specs. Maybe your fluid gets too thin at temperature and/or bubbles with air.

 

[jsjsteven]

No it did not do this prior to fluid change and I used aftermarket fluid from local farm supply that claims to meet JD specs. If nothing else works I may try swapping to Hy-Gard

 

[country101]

From what I understand, hydraulic fluid doesn't have standards. If you ever noticed people's loaders squealing, it's likely they used a cheap fluid. When it heats up you notice the difference. Friction modifiers, antifoaming , and all the other additives, in addition to a better quality oil base is where the difference is. I would say you need to use hyguard.

 

[beenthere]

I would suggest knowing if you should use Hy-Gard or Low Vis Hy-Gard.

Just changed the transaxle fluid in my 4x2 Gator and didn't know that Low-Vis was not recommended.. just Hy-Gard.
Regardless, the transaxle is working a lot better with less brake squeal and not popping out of drive and free-wheeling. Didn't realize that was a sign of needing new oil in the transaxle.

Deere publishes a mag, called The Furrow.
What country101 said was mentioned in one issue, that there are no checks if oils meet the industry standards.. they can freely state that they meet the standards but no one to check that they do.

 

[kthompson]

Seems like there was a lawsuit in maybe Oklahoma on hyd being sold saying it met certain standards and it did not. This was not long ago and believe it was discussed here.