I think I blew the 4th transmission on our tractor again. Instead of paying through the nose by sending to the dealer again, I was wondering how difficult it was to purchase and install one if you are not all that mechanical ? If I chose to do it, where can I purchase one cheaper that through the dealer ? Thanks in advance

It is not hard to replace the transmission. It takes about 30 minutes or less. The trans you have is made by Tuff Torq. I don't believe you can buy it other than a dealer. Are you pulling something heavy? These are good trans and will not wear out like that under normal use.

Perhaps he could locate a used trans somewhere. I agree doug, he should not be wearing out trans that quick with proper usage.

We go up a lot of hills and push the snow blower... Any ideas where I can find a used transmission ?

The K46 transaxle used in the L120 and at least one sears model is junk.
They are okay for very light use. But if you pull the little trailer or have a large yard; they are likely to quit around 200 hours. If you do a internet search for the "L120 transaxle" You will see what I mean! I have talked with the JD dealer, They know about the problem. They sell no parts for this axle. They will replace the axle(about $900) but it too will fail in around 200 hours. The dealer suggested I drain the trans and replace it with 10-50 motor oil. I did this, it worked for about 50 hours. Then quit again. I opened the trans; it was a mess inside. I found bearing races broken and surfaces damaged. Junk! BUT I have a good engine, if I find something to put it in.
If you are lucky enough to have one of these and it hasn't gave you any trouble. Before you use it again. Change the trans oil. Get a good synthetic hydraulic oil. To do this you need to pull the transaxle. Then remove the vent plug (little black plastic plug on top) while you have it upside down install a drain plug. Be careful the bottom is very thin. But there are two bosses on the bottom, use the outside one. It is thicker there. There is a man selling a upgrade kit with a K66 transaxle, much better unit. Good Luck

One of the problems with the John Deere L120 is that the Hydrostat control pedal has no bushings in it. After a few hundred hours the holes the pedal shaft pivots in wear out. Mine was barely able to back up on level ground and ran about 1/2 speed in forward. I explained this to my John Deere dealer and they asked how many hours. I told them 250 and they said I needed a transmission. Over 700 bucks! I got it, put it in, and it only worked slightly better. The problem is that the control lever on the Tuff Torq transmission has a VERY short travel, only about 1/4" forward and 1/8" backward. If your pedal holes are worn very badly, when you push the pedal you are not moving the lever as much. If you have the above symptoms, you probably need to fix your control pedal, not replace your transmission. I drilled my pedal holes out and put a bushing in that goes the entire length of the pedal shaft. I welded it on the ends and put grease on the shaft and bushing. NIce and tight. You can get the replacement parts from John Deere also. A lot cheaper than a transmission!

I saw a post on here about changing the oil. The Tuff Torque people told me to put Castrol GTX synthetic straight 30w in it. Mine has 360 hours on it, and runs great. I change it every 100 hours. Tuff Torq also sells a set of magnets to put in it to catch metal filings.

Something I forgot to mention in my previous post is that the Tuff Torq people also told me the K46 transmission is not a "ground engaging" transmission. You cannot push snow, pull a plow, anything like that. It will not be able to do those things. You can pull a very light trailer intermittently, but that's about it.

I parted my L120 out. Took the engine and put it an old 1984 Murray that I had.
Use it for something just about every day. Not one piece of plastic on it.
Just recently re-painted it. Should last another 10 years. I used to think JD was the best. But now one has to paid enough to buy a farm tractor to get a decent rider.
BTW:
Two John Deere dealers told me the same thing. That the L120 transaxle had a 200 hours life time, even with lite use. My lawn is all level, and the only thing I ever pulled, was the little trailer that came with it, full of leaves.

How much fluid is thransaxle supposed to hold?