JD550E transmission quits working when it warms up.

[miksa24]

I have an older JD550E. Run great and everything works fine until it warms up and looses all power in the transmission. Once it cools down it works fine again. Any ideas?

[Jim B]

Welcome,

Does the info on your serial number tag read like: 550 E 000000 T ? For the most part if the letter suffix is continuous with the numbers it is a model series. If there is a space between the model numbers and the suffix letter, the letter designates equipment. So if there is a space between the 550 and the E on your tag, it means you have a 550 with and E (#6415) dozer blade. The 6 digits are the serial number and will establish a year, the T means it was built at the Dubuque Tractor works. There is no Parts Catalog, Operator's Manual, or Technical Manual for a 550E (C or D either) on the JD Technical Publications site.

Some basic questions to start with. Do you have the manuals for it? You are likely going to need to check adjustments and pressures and will need info from the manuals. When was the transmission filter last changed and the screen in the transmission cleaned? What are you using for oil in it? Do you have an idea of the hours on it?

There are posts on the board of others dealing with similar transmission problems you can review to get an idea of what you will be looking at to diagnose this. You should have the H-L-R transmission similar to most of the 450s up through the E series.

[miksa24]

Thanks for the info Jim. Serial number is 550-E 361250T. We haven't done any maintenance on it yet but plan to when i can find a manual for how much and what kinds of fluids and filters it takes. I'll try reading into some of those other posts.

[Jim B]

By your serial number it is a 1980 550 with a 6415 dozer blade (outside blade with tilt). 1980 serial numbers were 340920 through 365417, per the list on the FAQ board here.

You should have the Operator's and Technical manuals. Send Lavoy an email (postmaster@jdcrawlers.com) and he will likely be able to help you with manuals. He, and his store, provide this site for us to use. He repairs "vintage" JD dozers as well as selling parts, so he knows quality parts.

You can use the parts catalogs on line for free at https://jdparts.deere.com/servlet/com.d ... anguage=19 to look at the drawings and find part numbers. Have your serial number handy in case there are production changes.

[JWB Contracting]

You need to do gauge tests on both the high pressure oil coming from the pump and the regulated oil for operation. I would suggest installing 2 gauges and operate while watching the pressures. I got lucky on the last one / only one we have had to work on, turned out to be the torque pump. I did not have to go thru the shifting sequence testing which looked fairly in depth.