LS MT 125 Transmission (possible) Problem

Catahoulabuddy · Feb 24, 2020

Hey ya'll,

Transmission seems to be acting up on my MT 125. With high gear or low gear it seems to take a lot more effort to provide power from the pedal to the drive and there is a weird sound that is slightly different from the hydrostatic whine, almost like a vibration. Still moves but if there is a problem I want to jump on it before it gets worse. Tractor is a year old with 165 miles on it and the filter has been changed once at 50 hours service. Most of the hours used on the tractor have been using the backhoe and the front end loader to scrape up brush. There is a decent amount of mud on the property and the tractor has been driven over saplings, so there could be something that got knock or has a stick restricting it. I try to be careful with the tractor and pay attention to hydraulic heat when running the backhoe to prevent damage to the system, but I also don't baby it.

What should I check out first? Is it possible to just buy a new pump and install it? The dealer is ok but is pretty slow with repairs and I don't want it to be sitting for a month.

LScraig · Feb 24, 2020

It might not be the transmission. It's possible a wheel is spinning inside the tire due to a bad bead seal, or low air pressure. Have someone watch the wheels while you drive the tractor.

jaydee325 · Feb 24, 2020

Did this happen all of a sudden when you were driving over saplings or through mud?

Clean off any mud so you can see what you have underneath. Next I'd check for any sticks or debris that could be lodged in the brake linkage or in the linkage from the hydro peddles. Also check for any bent linkage.

Sounds like you may have the brakes partially applied.

Catahoulabuddy · Feb 24, 2020

It wasn't really a sudden thing but the brakes linkage makes sense. I'll clean it off and take a look. Half the reason I got the 125 was for weight and moving around the swampy areas.

Catahoulabuddy · Feb 24, 2020

This could be it. I checked the air the day before and the tire pressure on the front tires was about 15 psi, I pumped then back up to 22 psi and that afternoon is when I noticed the problem. Thanks for the advice.

Skipper T · Feb 14, 2021

I am a new MT 125 owner myself and have about 35 hrs on my machine. While under it running wires for ROPs lights, I saw there is a plastic fan for cooling the transmission and hydraulic fluid, check to make sure it hasn't been jammed or broken. This could be making the unusual sound.

LS Tractor Owner · Feb 15, 2021

Skipper T said:
I am a new MT 125 owner myself and have about 35 hrs on my machine. While under it running wires for ROPs lights, I saw there is a plastic fan for cooling the transmission and hydraulic fluid, check to make sure it hasn't been jammed or broken. This could be making the unusual sound.

I'm sure he found the problem by now.... it's been almost a year and he has never posted since.....